Commit Graph

22564 Commits

Author SHA1 Message Date
Nicholas Piggin
cdb1ea0276 powerpc/pseries: add new branch prediction security bits for link stack
The hypervisor interface has defined branch prediction security bits for
handling the link stack. Wire them up.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200825075612.224656-1-npiggin@gmail.com
2020-10-06 23:22:23 +11:00
Nicholas Piggin
05504b4256 powerpc/64s: Add cp_abort after tlbiel to invalidate copy-buffer address
The copy buffer is implemented as a real address in the nest which is
translated from EA by copy, and used for memory access by paste. This
requires that it be invalidated by TLB invalidation.

TLBIE does invalidate the copy buffer, but TLBIEL does not. Add
cp_abort to the tlbiel sequence.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fixup whitespace and comment formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200916030234.4110379-2-npiggin@gmail.com
2020-10-06 23:22:23 +11:00
Nicholas Piggin
9983efa83b powerpc: untangle cputable mce include
Having cputable.h include mce.h means it pulls in a bunch of low level
headers (e.g., synch.h) which then can't use CPU_FTR_ definitions.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200916030234.4110379-1-npiggin@gmail.com
2020-10-06 23:22:22 +11:00
Mahesh Salgaonkar
aea948bb80 powerpc/powernv/elog: Fix race while processing OPAL error log event.
Every error log reported by OPAL is exported to userspace through a
sysfs interface and notified using kobject_uevent(). The userspace
daemon (opal_errd) then reads the error log and acknowledges the error
log is saved safely to disk. Once acknowledged the kernel removes the
respective sysfs file entry causing respective resources to be
released including kobject.

However it's possible the userspace daemon may already be scanning
elog entries when a new sysfs elog entry is created by the kernel.
User daemon may read this new entry and ack it even before kernel can
notify userspace about it through kobject_uevent() call. If that
happens then we have a potential race between
elog_ack_store->kobject_put() and kobject_uevent which can lead to
use-after-free of a kernfs object resulting in a kernel crash. eg:

  BUG: Unable to handle kernel data access on read at 0x6b6b6b6b6b6b6bfb
  Faulting instruction address: 0xc0000000008ff2a0
  Oops: Kernel access of bad area, sig: 11 [#1]
  LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA PowerNV
  CPU: 27 PID: 805 Comm: irq/29-opal-elo Not tainted 5.9.0-rc2-gcc-8.2.0-00214-g6f56a67bcbb5-dirty #363
  ...
  NIP kobject_uevent_env+0xa0/0x910
  LR  elog_event+0x1f4/0x2d0
  Call Trace:
    0x5deadbeef0000122 (unreliable)
    elog_event+0x1f4/0x2d0
    irq_thread_fn+0x4c/0xc0
    irq_thread+0x1c0/0x2b0
    kthread+0x1c4/0x1d0
    ret_from_kernel_thread+0x5c/0x6c

This patch fixes this race by protecting the sysfs file
creation/notification by holding a reference count on kobject until we
safely send kobject_uevent().

The function create_elog_obj() returns the elog object which if used
by caller function will end up in use-after-free problem again.
However, the return value of create_elog_obj() function isn't being
used today and there is no need as well. Hence change it to return
void to make this fix complete.

Fixes: 774fea1a38 ("powerpc/powernv: Read OPAL error log and export it through sysfs")
Cc: stable@vger.kernel.org # v3.15+
Reported-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
[mpe: Rework the logic to use a single return, reword comments, add oops]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201006122051.190176-1-mpe@ellerman.id.au
2020-10-06 23:22:22 +11:00
Dan Williams
ec6347bb43 x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()
In reaction to a proposal to introduce a memcpy_mcsafe_fast()
implementation Linus points out that memcpy_mcsafe() is poorly named
relative to communicating the scope of the interface. Specifically what
addresses are valid to pass as source, destination, and what faults /
exceptions are handled.

Of particular concern is that even though x86 might be able to handle
the semantics of copy_mc_to_user() with its common copy_user_generic()
implementation other archs likely need / want an explicit path for this
case:

  On Fri, May 1, 2020 at 11:28 AM Linus Torvalds <torvalds@linux-foundation.org> wrote:
  >
  > On Thu, Apr 30, 2020 at 6:21 PM Dan Williams <dan.j.williams@intel.com> wrote:
  > >
  > > However now I see that copy_user_generic() works for the wrong reason.
  > > It works because the exception on the source address due to poison
  > > looks no different than a write fault on the user address to the
  > > caller, it's still just a short copy. So it makes copy_to_user() work
  > > for the wrong reason relative to the name.
  >
  > Right.
  >
  > And it won't work that way on other architectures. On x86, we have a
  > generic function that can take faults on either side, and we use it
  > for both cases (and for the "in_user" case too), but that's an
  > artifact of the architecture oddity.
  >
  > In fact, it's probably wrong even on x86 - because it can hide bugs -
  > but writing those things is painful enough that everybody prefers
  > having just one function.

Replace a single top-level memcpy_mcsafe() with either
copy_mc_to_user(), or copy_mc_to_kernel().

Introduce an x86 copy_mc_fragile() name as the rename for the
low-level x86 implementation formerly named memcpy_mcsafe(). It is used
as the slow / careful backend that is supplanted by a fast
copy_mc_generic() in a follow-on patch.

One side-effect of this reorganization is that separating copy_mc_64.S
to its own file means that perf no longer needs to track dependencies
for its memcpy_64.S benchmarks.

 [ bp: Massage a bit. ]

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: <stable@vger.kernel.org>
Link: http://lore.kernel.org/r/CAHk-=wjSqtXAqfUJxFtWNwmguFASTgB0dz1dT3V-78Quiezqbg@mail.gmail.com
Link: https://lkml.kernel.org/r/160195561680.2163339.11574962055305783722.stgit@dwillia2-desk3.amr.corp.intel.com
2020-10-06 11:18:04 +02:00
Christoph Hellwig
9f4df96b87 dma-mapping: merge <linux/dma-noncoherent.h> into <linux/dma-map-ops.h>
Move more nitty gritty DMA implementation details into the common
internal header.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:06 +02:00
Christoph Hellwig
0a0f0d8be7 dma-mapping: split <linux/dma-mapping.h>
Split out all the bits that are purely for dma_map_ops implementations
and related code into a new <linux/dma-map-ops.h> header so that they
don't get pulled into all the drivers.  That also means the architecture
specific <asm/dma-mapping.h> is not pulled in by <linux/dma-mapping.h>
any more, which leads to a missing includes that were pulled in by the
x86 or arm versions in a few not overly portable drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-10-06 07:07:03 +02:00
David S. Miller
8b0308fe31 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Rejecting non-native endian BTF overlapped with the addition
of support for it.

The rest were more simple overlapping changes, except the
renesas ravb binding update, which had to follow a file
move as well as a YAML conversion.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-05 18:40:01 -07:00
Vladimir Oltean
e69eb0824d powerpc: dts: t1040rdb: add ports for Seville Ethernet switch
Define the network interface names for the switch ports and hook them up
to the 2 QSGMII PHYs that are onboard.

A conscious decision was taken to go along with the numbers that are
written on the front panel of the board and not with the hardware
numbers of the switch chip ports.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Maxim Kochetkov <fido_max@inbox.ru>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-03 17:02:42 -07:00
Vladimir Oltean
aa3098676c powerpc: dts: t1040: add bindings for Seville Ethernet switch
Add the description of the embedded L2 switch inside the SoC dtsi file
for NXP T1040.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Maxim Kochetkov <fido_max@inbox.ru>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-03 17:02:42 -07:00
Christoph Hellwig
c3973b401e mm: remove compat_process_vm_{readv,writev}
Now that import_iovec handles compat iovecs, the native syscalls
can be used for the compat case as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-10-03 00:02:15 -04:00
Christoph Hellwig
598b3cec83 fs: remove compat_sys_vmsplice
Now that import_iovec handles compat iovecs, the native vmsplice syscall
can be used for the compat case as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-10-03 00:02:15 -04:00
Christoph Hellwig
5f764d624a fs: remove the compat readv/writev syscalls
Now that import_iovec handles compat iovecs, the native readv and writev
syscalls can be used for the compat case as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-10-03 00:02:14 -04:00
David S. Miller
1f25c9bbfd Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Alexei Starovoitov says:

====================
pull-request: bpf 2020-09-29

The following pull-request contains BPF updates for your *net* tree.

We've added 7 non-merge commits during the last 14 day(s) which contain
a total of 7 files changed, 28 insertions(+), 8 deletions(-).

The main changes are:

1) fix xdp loading regression in libbpf for old kernels, from Andrii.

2) Do not discard packet when NETDEV_TX_BUSY, from Magnus.

3) Fix corner cases in libbpf related to endianness and kconfig, from Tony.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-30 01:49:20 -07:00
He Zhe
9cf51446e6 bpf, powerpc: Fix misuse of fallthrough in bpf_jit_comp()
The user defined label following "fallthrough" is not considered by GCC
and causes build failure.

kernel-source/include/linux/compiler_attributes.h:208:41: error: attribute
'fallthrough' not preceding a case label or default label [-Werror]
 208   define fallthrough _attribute((fallthrough_))
                          ^~~~~~~~~~~~~

Fixes: df561f6688 ("treewide: Use fallthrough pseudo-keyword")
Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/bpf/20200928090023.38117-1-zhe.he@windriver.com
2020-09-29 16:39:11 +02:00
Thomas Gleixner
981aa1d366 PCI: MSI: Fix Kconfig dependencies for PCI_MSI_ARCH_FALLBACKS
The unconditional selection of PCI_MSI_ARCH_FALLBACKS has an unmet
dependency because PCI_MSI_ARCH_FALLBACKS is defined in a 'if PCI' clause.

As it is only relevant when PCI_MSI is enabled, update the affected
architecture Kconfigs to make the selection of PCI_MSI_ARCH_FALLBACKS
depend on 'if PCI_MSI'.

Fixes: 077ee78e39 ("PCI/MSI: Make arch_.*_msi_irq[s] fallbacks selectable")
Reported-by: Qian Cai <cai@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Links: https://lore.kernel.org/r/cdfd63305caa57785b0925dd24c0711ea02c8527.camel@redhat.com
2020-09-28 16:03:10 +02:00
Christoph Hellwig
efa70f2fdc dma-mapping: add a new dma_alloc_pages API
This API is the equivalent of alloc_pages, except that the returned memory
is guaranteed to be DMA addressable by the passed in device.  The
implementation will also be used to provide a more sensible replacement
for DMA_ATTR_NON_CONSISTENT flag.

Additionally dma_alloc_noncoherent is switched over to use dma_alloc_pages
as its backend.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> (MIPS part)
2020-09-25 06:20:47 +02:00
Christoph Hellwig
8c1c6c7588 Merge branch 'master' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into dma-mapping-for-next
Pull in the latest 5.9 tree for the commit to revert the
V4L2_FLAG_MEMORY_NON_CONSISTENT uapi addition.
2020-09-25 06:19:19 +02:00
Masahiro Yamada
596b0474d3 kbuild: preprocess module linker script
There was a request to preprocess the module linker script like we
do for the vmlinux one. (https://lkml.org/lkml/2020/8/21/512)

The difference between vmlinux.lds and module.lds is that the latter
is needed for external module builds, thus must be cleaned up by
'make mrproper' instead of 'make clean'. Also, it must be created
by 'make modules_prepare'.

You cannot put it in arch/$(SRCARCH)/kernel/, which is cleaned up by
'make clean'. I moved arch/$(SRCARCH)/kernel/module.lds to
arch/$(SRCARCH)/include/asm/module.lds.h, which is included from
scripts/module.lds.S.

scripts/module.lds is fine because 'make clean' keeps all the
build artifacts under scripts/.

You can add arch-specific sections in <asm/module.lds.h>.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
2020-09-25 00:36:41 +09:00
Christoph Hellwig
028abd9222 fs: remove compat_sys_mount
compat_sys_mount is identical to the regular sys_mount now, so remove it
and use the native version everywhere.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-22 23:45:57 -04:00
Paolo Bonzini
2e3df760cd PPC KVM update for 5.10
- Fix for running nested guests with in-kernel IRQ chip
 - Fix race condition causing occasional host hard lockup
 - Minor cleanups and bugfixes
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Merge tag 'kvm-ppc-next-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD

PPC KVM update for 5.10

- Fix for running nested guests with in-kernel IRQ chip
- Fix race condition causing occasional host hard lockup
- Minor cleanups and bugfixes
2020-09-22 08:18:16 -04:00
Wang Wensheng
cf59eb13e1 KVM: PPC: Book3S: Fix symbol undeclared warnings
Build the kernel with `C=2`:
arch/powerpc/kvm/book3s_hv_nested.c:572:25: warning: symbol
'kvmhv_alloc_nested' was not declared. Should it be static?
arch/powerpc/kvm/book3s_64_mmu_radix.c:350:6: warning: symbol
'kvmppc_radix_set_pte_at' was not declared. Should it be static?
arch/powerpc/kvm/book3s_hv.c:3568:5: warning: symbol
'kvmhv_p9_guest_entry' was not declared. Should it be static?
arch/powerpc/kvm/book3s_hv_rm_xics.c:767:15: warning: symbol 'eoi_rc'
was not declared. Should it be static?
arch/powerpc/kvm/book3s_64_vio_hv.c:240:13: warning: symbol
'iommu_tce_kill_rm' was not declared. Should it be static?
arch/powerpc/kvm/book3s_64_vio.c:492:6: warning: symbol
'kvmppc_tce_iommu_do_map' was not declared. Should it be static?
arch/powerpc/kvm/book3s_pr.c:572:6: warning: symbol 'kvmppc_set_pvr_pr'
was not declared. Should it be static?

Those symbols are used only in the files that define them so make them
static to fix the warnings.

Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-09-22 11:53:55 +10:00
Jing Xiangfeng
eb173559c9 KVM: PPC: Book3S: Remove redundant initialization of variable ret
The variable ret is being initialized with '-ENOMEM' that is meaningless.
So remove it.

Signed-off-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-09-22 11:53:55 +10:00
Qinglang Miao
4517076608 KVM: PPC: Book3S HV: XIVE: Convert to DEFINE_SHOW_ATTRIBUTE
Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.

Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-09-22 11:53:55 +10:00
Linus Torvalds
5a55d36f71 powerpc fixes for 5.9 #5
Opt us out of the DEBUG_VM_PGTABLE support for now as it's causing crashes.
 
 Fix a long standing bug in our DMA mask handling that was hidden until recently,
 and which caused problems with some drivers.
 
 Fix a boot failure on systems with large amounts of RAM, and no hugepage support
 and using Radix MMU, only seen in the lab.
 
 A few other minor fixes.
 
 Thanks to:
   Alexey Kardashevskiy, Aneesh Kumar K.V, Gautham R. Shenoy, Hari Bathini, Ira
   Weiny, Nick Desaulniers, Shirisha Ganta, Vaibhav Jain, Vaidyanathan
   Srinivasan.
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Merge tag 'powerpc-5.9-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "Some more powerpc fixes for 5.9:

   - Opt us out of the DEBUG_VM_PGTABLE support for now as it's causing
     crashes.

   - Fix a long standing bug in our DMA mask handling that was hidden
     until recently, and which caused problems with some drivers.

   - Fix a boot failure on systems with large amounts of RAM, and no
     hugepage support and using Radix MMU, only seen in the lab.

   - A few other minor fixes.

  Thanks to Alexey Kardashevskiy, Aneesh Kumar K.V, Gautham R. Shenoy,
  Hari Bathini, Ira Weiny, Nick Desaulniers, Shirisha Ganta, Vaibhav
  Jain, and Vaidyanathan Srinivasan"

* tag 'powerpc-5.9-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/papr_scm: Limit the readability of 'perf_stats' sysfs attribute
  cpuidle: pseries: Fix CEDE latency conversion from tb to us
  powerpc/dma: Fix dma_map_ops::get_required_mask
  Revert "powerpc/build: vdso linker warning for orphan sections"
  powerpc/mm: Remove DEBUG_VM_PGTABLE support on powerpc
  selftests/powerpc: Skip PROT_SAO test in guests/LPARS
  powerpc/book3s64/radix: Fix boot failure with large amount of guest memory
2020-09-18 11:48:25 -07:00
Cédric Le Goater
ebbfeef0d8 powerpc/32: Declare stack_overflow_exception() prototype
This fixes a compile error with W=1.

CC      arch/powerpc/kernel/traps.o
../arch/powerpc/kernel/traps.c:1663:6: error: no previous prototype for ‘stack_overflow_exception’ [-Werror=missing-prototypes]
 void stack_overflow_exception(struct pt_regs *regs)
      ^~~~~~~~~~~~~~~~~~~~~~~~

Fixes: 3978eb7851 ("powerpc/32: Add early stack overflow detection with VMAP stack.")
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200914211007.2285999-8-clg@kaod.org
2020-09-18 20:05:25 +10:00
Cédric Le Goater
2228f19cf9 powerpc/xive: Make debug routines static
This fixes a compile error with W=1.

CC      arch/powerpc/sysdev/xive/common.o
../arch/powerpc/sysdev/xive/common.c:1568:6: error: no previous prototype for ‘xive_debug_show_cpu’ [-Werror=missing-prototypes]
 void xive_debug_show_cpu(struct seq_file *m, int cpu)
      ^~~~~~~~~~~~~~~~~~~
../arch/powerpc/sysdev/xive/common.c:1602:6: error: no previous prototype for ‘xive_debug_show_irq’ [-Werror=missing-prototypes]
 void xive_debug_show_irq(struct seq_file *m, u32 hw_irq, struct irq_data *d)
      ^~~~~~~~~~~~~~~~~~~

Fixes: 930914b7d5 ("powerpc/xive: Add a debugfs file to dump internal XIVE state")
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200914211007.2285999-5-clg@kaod.org
2020-09-18 20:05:25 +10:00
Cédric Le Goater
5ab187e01a powerpc/sstep: Remove empty if statement checking for invalid form
The check should be performed by the caller. This fixes a compile
error with W=1.

../arch/powerpc/lib/sstep.c: In function ‘mlsd_8lsd_ea’:
../arch/powerpc/lib/sstep.c:225:3: error: suggest braces around empty body in an ‘if’ statement [-Werror=empty-body]
   ; /* Invalid form. Should already be checked for by caller! */
   ^

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200914211007.2285999-4-clg@kaod.org
2020-09-18 20:05:24 +10:00
Cédric Le Goater
7b2aab5f22 powerpc/sysfs: Remove unused 'err' variable in sysfs_create_dscr_default()
This fixes a compile error with W=1.

arch/powerpc/kernel/sysfs.c: In function ‘sysfs_create_dscr_default’:
arch/powerpc/kernel/sysfs.c:228:7: error: variable ‘err’ set but not used [-Werror=unused-but-set-variable]
   int err = 0;
       ^~~
cc1: all warnings being treated as errors

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200914211007.2285999-2-clg@kaod.org
2020-09-18 20:05:24 +10:00
Qinglang Miao
8ec5cb12cd powerpc/powernv: fix wrong warning message in opalcore_config_init()
The logic of the warn output is incorrect. The two args should be
exchanged.

Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200916062129.190864-1-miaoqinglang@huawei.com
2020-09-18 19:59:45 +10:00
Michael Ellerman
6c71cfcc01 powerpc/prom_init: Check display props exist before enabling btext
It's possible to enable CONFIG_PPC_EARLY_DEBUG_BOOTX for a pseries
kernel (maybe it shouldn't be), which is then booted with qemu/slof.

But if you do that the kernel crashes in draw_byte(), with a DAR
pointing somewhere near INT_MAX.

Adding some debug to prom_init we see that we're not able to read the
"address" property from OF, so we're just using whatever junk value
was on the stack.

So check the properties can be read properly from OF, if not we bail
out before initialising btext, which avoids the crash.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Link: https://lore.kernel.org/r/20200821103407.3362149-1-mpe@ellerman.id.au
2020-09-18 19:59:44 +10:00
Michael Ellerman
39f8756145 powerpc/smp: Move ppc_md.cpu_die() to smp_ops.cpu_offline_self()
We have smp_ops->cpu_die() and ppc_md.cpu_die(). One of them offlines
the current CPU and one offlines another CPU, can you guess which is
which? Also one is in smp_ops and one is in ppc_md?

So rename ppc_md.cpu_die(), to cpu_offline_self(), because that's what
it does. And move it into smp_ops where it belongs.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015634.1974478-3-mpe@ellerman.id.au
2020-09-18 19:59:43 +10:00
Michael Ellerman
bf3c1464db powerpc/smp: Fold cpu_die() into its only caller
Avoid the eternal confusion between cpu_die() and __cpu_die() by
removing the former, folding it into its only caller.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015634.1974478-2-mpe@ellerman.id.au
2020-09-18 19:59:43 +10:00
Michael Ellerman
1ea21ba231 powerpc: Move arch_cpu_idle_dead() into smp.c
arch_cpu_idle_dead() is in idle.c, which makes sense, but it's inside
a CONFIG_HOTPLUG_CPU block.

It would be more at home in smp.c, inside the existing
CONFIG_HOTPLUG_CPU block. Note that CONFIG_HOTPLUG_CPU depends on
CONFIG_SMP so even though smp.c is not built for SMP=n builds, that's
fine.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015634.1974478-1-mpe@ellerman.id.au
2020-09-18 19:59:43 +10:00
Michael Ellerman
d10ebe79df powerpc/perf: Add declarations to fix sparse warnings
Sparse warns about all the init functions:
  symbol init_ppc970_pmu was not declared. Should it be static?
  symbol init_power5p_pmu was not declared. Should it be static?
  symbol init_power5_pmu was not declared. Should it be static?
  symbol init_power6_pmu was not declared. Should it be static?
  symbol init_power7_pmu was not declared. Should it be static?
  symbol init_power9_pmu was not declared. Should it be static?
  symbol init_power8_pmu was not declared. Should it be static?
  symbol init_generic_compat_pmu was not declared. Should it be static?

They're already declared in internal.h, so just make sure all the C
files include that directly or indirectly.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://lore.kernel.org/r/20200916115637.3100484-2-mpe@ellerman.id.au
2020-09-18 19:59:43 +10:00
Michael Ellerman
ef1edbba52 powerpc/mm/64s: Fix slb_setup_new_exec() sparse warning
Sparse says:
  symbol slb_setup_new_exec was not declared. Should it be static?

No, it should have a declaration in a header, add one.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200916115637.3100484-1-mpe@ellerman.id.au
2020-09-18 19:59:43 +10:00
Liu Shixin
96543e7352 powerpc/pseries: convert to use DEFINE_SEQ_ATTRIBUTE macro
Use DEFINE_SEQ_ATTRIBUTE macro to simplify the code.

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200916025026.3992835-1-liushixin2@huawei.com
2020-09-18 19:59:43 +10:00
Yang Yingliang
bda7673d64 powerpc/book3s64: fix link error with CONFIG_PPC_RADIX_MMU=n
Fix link error when CONFIG_PPC_RADIX_MMU is disabled:
powerpc64-linux-gnu-ld: arch/powerpc/platforms/pseries/lpar.o:(.toc+0x0): undefined reference to `mmu_pid_bits'

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200917020643.90375-1-yangyingliang@huawei.com
2020-09-18 19:59:43 +10:00
Michael Ellerman
0b30191b27 Merge branch 'topic/irqs-off-activate-mm' into next
Merge Nick's series to add ARCH_WANT_IRQS_OFF_ACTIVATE_MM.
2020-09-18 18:14:06 +10:00
Michael Ellerman
d208e13c6a powerpc/process: Fix uninitialised variable error
Clang, and GCC with -Wmaybe-uninitialized, can't see that val is
unused in get_fpexec_mode():

  arch/powerpc/kernel/process.c:1940:7: error: variable 'val' is used
  uninitialized whenever 'if' condition is true
		  if (cpu_has_feature(CPU_FTR_SPE)) {
		      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~

We know that CPU_FTR_SPE will only be true iff CONFIG_SPE is also
true, but the compiler doesn't.

Avoid it by initialising val to zero.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 532ed1900d ("powerpc/process: Remove useless #ifdef CONFIG_SPE")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20200917024509.3253837-1-mpe@ellerman.id.au
2020-09-18 18:12:46 +10:00
Christoph Hellwig
cc7886d25b compat: lift compat_s64 and compat_u64 to <asm-generic/compat.h>
lift the compat_s64 and compat_u64 definitions into common code using the
COMPAT_FOR_U64_ALIGNMENT symbol for the x86 special case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-17 13:00:46 -04:00
Paul Mackerras
35dfb43c24 KVM: PPC: Book3S HV: Set LPCR[HDICE] before writing HDEC
POWER8 and POWER9 machines have a hardware deviation where generation
of a hypervisor decrementer exception is suppressed if the HDICE bit
in the LPCR register is 0 at the time when the HDEC register
decrements from 0 to -1.  When entering a guest, KVM first writes the
HDEC register with the time until it wants the CPU to exit the guest,
and then writes the LPCR with the guest value, which includes
HDICE = 1.  If HDEC decrements from 0 to -1 during the interval
between those two events, it is possible that we can enter the guest
with HDEC already negative but no HDEC exception pending, meaning that
no HDEC interrupt will occur while the CPU is in the guest, or at
least not until HDEC wraps around.  Thus it is possible for the CPU to
keep executing in the guest for a long time; up to about 4 seconds on
POWER8, or about 4.46 years on POWER9 (except that the host kernel
hard lockup detector will fire first).

To fix this, we set the LPCR[HDICE] bit before writing HDEC on guest
entry.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-09-17 11:38:17 +10:00
Fabiano Rosas
05e6295dc7 KVM: PPC: Book3S HV: Do not allocate HPT for a nested guest
The current nested KVM code does not support HPT guests. This is
informed/enforced in some ways:

- Hosts < P9 will not be able to enable the nested HV feature;

- The nested hypervisor MMU capabilities will not contain
  KVM_CAP_PPC_MMU_HASH_V3;

- QEMU reflects the MMU capabilities in the
  'ibm,arch-vec-5-platform-support' device-tree property;

- The nested guest, at 'prom_parse_mmu_model' ignores the
  'disable_radix' kernel command line option if HPT is not supported;

- The KVM_PPC_CONFIGURE_V3_MMU ioctl will fail if trying to use HPT.

There is, however, still a way to start a HPT guest by using
max-compat-cpu=power8 at the QEMU machine options. This leads to the
guest being set to use hash after QEMU calls the KVM_PPC_ALLOCATE_HTAB
ioctl.

With the guest set to hash, the nested hypervisor goes through the
entry path that has no knowledge of nesting (kvmppc_run_vcpu) and
crashes when it tries to execute an hypervisor-privileged (mtspr
HDEC) instruction at __kvmppc_vcore_entry:

root@L1:~ $ qemu-system-ppc64 -machine pseries,max-cpu-compat=power8 ...

<snip>
[  538.543303] CPU: 83 PID: 25185 Comm: CPU 0/KVM Not tainted 5.9.0-rc4 #1
[  538.543355] NIP:  c00800000753f388 LR: c00800000753f368 CTR: c0000000001e5ec0
[  538.543417] REGS: c0000013e91e33b0 TRAP: 0700   Not tainted  (5.9.0-rc4)
[  538.543470] MSR:  8000000002843033 <SF,VEC,VSX,FP,ME,IR,DR,RI,LE>  CR: 22422882  XER: 20040000
[  538.543546] CFAR: c00800000753f4b0 IRQMASK: 3
               GPR00: c0080000075397a0 c0000013e91e3640 c00800000755e600 0000000080000000
               GPR04: 0000000000000000 c0000013eab19800 c000001394de0000 00000043a054db72
               GPR08: 00000000003b1652 0000000000000000 0000000000000000 c0080000075502e0
               GPR12: c0000000001e5ec0 c0000007ffa74200 c0000013eab19800 0000000000000008
               GPR16: 0000000000000000 c00000139676c6c0 c000000001d23948 c0000013e91e38b8
               GPR20: 0000000000000053 0000000000000000 0000000000000001 0000000000000000
               GPR24: 0000000000000001 0000000000000001 0000000000000000 0000000000000001
               GPR28: 0000000000000001 0000000000000053 c0000013eab19800 0000000000000001
[  538.544067] NIP [c00800000753f388] __kvmppc_vcore_entry+0x90/0x104 [kvm_hv]
[  538.544121] LR [c00800000753f368] __kvmppc_vcore_entry+0x70/0x104 [kvm_hv]
[  538.544173] Call Trace:
[  538.544196] [c0000013e91e3640] [c0000013e91e3680] 0xc0000013e91e3680 (unreliable)
[  538.544260] [c0000013e91e3820] [c0080000075397a0] kvmppc_run_core+0xbc8/0x19d0 [kvm_hv]
[  538.544325] [c0000013e91e39e0] [c00800000753d99c] kvmppc_vcpu_run_hv+0x404/0xc00 [kvm_hv]
[  538.544394] [c0000013e91e3ad0] [c0080000072da4fc] kvmppc_vcpu_run+0x34/0x48 [kvm]
[  538.544472] [c0000013e91e3af0] [c0080000072d61b8] kvm_arch_vcpu_ioctl_run+0x310/0x420 [kvm]
[  538.544539] [c0000013e91e3b80] [c0080000072c7450] kvm_vcpu_ioctl+0x298/0x778 [kvm]
[  538.544605] [c0000013e91e3ce0] [c0000000004b8c2c] sys_ioctl+0x1dc/0xc90
[  538.544662] [c0000013e91e3dc0] [c00000000002f9a4] system_call_exception+0xe4/0x1c0
[  538.544726] [c0000013e91e3e20] [c00000000000d140] system_call_common+0xf0/0x27c
[  538.544787] Instruction dump:
[  538.544821] f86d1098 60000000 60000000 48000099 e8ad0fe8 e8c500a0 e9264140 75290002
[  538.544886] 7d1602a6 7cec42a6 40820008 7d0807b4 <7d164ba6> 7d083a14 f90d10a0 480104fd
[  538.544953] ---[ end trace 74423e2b948c2e0c ]---

This patch makes the KVM_PPC_ALLOCATE_HTAB ioctl fail when running in
the nested hypervisor, causing QEMU to abort.

Reported-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-09-17 11:38:17 +10:00
Greg Kurz
4e1b2ab7e6 KVM: PPC: Don't return -ENOTSUPP to userspace in ioctls
ENOTSUPP is a linux only thingy, the value of which is unknown to
userspace, not to be confused with ENOTSUP which linux maps to
EOPNOTSUPP, as permitted by POSIX [1]:

[EOPNOTSUPP]
Operation not supported on socket. The type of socket (address family
or protocol) does not support the requested operation. A conforming
implementation may assign the same values for [EOPNOTSUPP] and [ENOTSUP].

Return -EOPNOTSUPP instead of -ENOTSUPP for the following ioctls:
- KVM_GET_FPU for Book3s and BookE
- KVM_SET_FPU for Book3s and BookE
- KVM_GET_DIRTY_LOG for BookE

This doesn't affect QEMU which doesn't call the KVM_GET_FPU and
KVM_SET_FPU ioctls on POWER anyway since they are not supported,
and _buggily_ ignores anything but -EPERM for KVM_GET_DIRTY_LOG.

[1] https://pubs.opengroup.org/onlinepubs/9699919799/functions/V2_chap02.html

Signed-off-by: Greg Kurz <groug@kaod.org>
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-09-17 11:38:17 +10:00
Thomas Gleixner
077ee78e39 PCI/MSI: Make arch_.*_msi_irq[s] fallbacks selectable
The arch_.*_msi_irq[s] fallbacks are compiled in whether an architecture
requires them or not. Architectures which are fully utilizing hierarchical
irq domains should never call into that code.

It's not only architectures which depend on that by implementing one or
more of the weak functions, there is also a bunch of drivers which relies
on the weak functions which invoke msi_controller::setup_irq[s] and
msi_controller::teardown_irq.

Make the architectures and drivers which rely on them select them in Kconfig
and if not selected replace them by stub functions which emit a warning and
fail the PCI/MSI interrupt allocation.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200826112333.992429909@linutronix.de
2020-09-16 16:52:37 +02:00
Srikar Dronamraju
fa35e868f9 powerpc/smp: Implement cpu_to_coregroup_id
Lookup the coregroup id from the associativity array.

If unable to detect the coregroup id, fallback on the core id.
This way, ensure sched_domain degenerates and an extra sched domain is
not created.

Ideally this function should have been implemented in
arch/powerpc/kernel/smp.c. However if its implemented in mm/numa.c, we
don't need to find the primary domain again.

If the device-tree mentions more than one coregroup, then kernel
implements only the last or the smallest coregroup, which currently
corresponds to the penultimate domain in the device-tree.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200810071834.92514-11-srikar@linux.vnet.ibm.com
2020-09-16 22:13:32 +10:00
Srikar Dronamraju
72730bfc2a powerpc/smp: Create coregroup domain
Add percpu coregroup maps and masks to create coregroup domain.
If a coregroup doesn't exist, the coregroup domain will be degenerated
in favour of SMT/CACHE domain. Do note this patch is only creating stubs
for cpu_to_coregroup_id. The actual cpu_to_coregroup_id implementation
would be in a subsequent patch.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200810071834.92514-10-srikar@linux.vnet.ibm.com
2020-09-16 22:13:32 +10:00
Srikar Dronamraju
6e08630281 powerpc/smp: Allocate cpumask only after searching thread group
If allocated earlier and the search fails, then cpu_l1_cache_map cpumask
is unnecessarily cleared. However cpu_l1_cache_map can be allocated /
cleared after we search thread group.

Please note CONFIG_CPUMASK_OFFSTACK is not set on Powerpc. Hence cpumask
allocated by zalloc_cpumask_var_node is never freed.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200810071834.92514-9-srikar@linux.vnet.ibm.com
2020-09-16 22:13:32 +10:00
Srikar Dronamraju
f9f130ff2e powerpc/numa: Detect support for coregroup
Add support for grouping cores based on the device-tree classification.
- The last domain in the associativity domains always refers to the
core.
- If primary reference domain happens to be the penultimate domain in
the associativity domains device-tree property, then there are no
coregroups. However if its not a penultimate domain, then there are
coregroups. There can be more than one coregroup. For now we would be
interested in the last or the smallest coregroups, i.e one sub-group
per DIE.

Currently there are no firmwares that are exposing this grouping. Hence
allow the basis for grouping to be abstract.  Once the firmware starts
using this grouping, code would be added to detect the type of grouping
and adjust the sd domain flags accordingly.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200810071834.92514-8-srikar@linux.vnet.ibm.com
2020-09-16 22:13:31 +10:00
Srikar Dronamraju
caa8e29da5 powerpc/smp: Optimize start_secondary
In start_secondary, even if shared_cache was already set, system does a
redundant match for cpumask. This redundant check can be removed by
checking if shared_cache is already set.

While here, localize the sibling_mask variable to within the if
condition.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200810071834.92514-7-srikar@linux.vnet.ibm.com
2020-09-16 22:13:31 +10:00
Srikar Dronamraju
f6606cfdfb powerpc/smp: Dont assume l2-cache to be superset of sibling
Current code assumes that cpumask of cpus sharing a l2-cache mask will
always be a superset of cpu_sibling_mask.

Lets stop that assumption. cpu_l2_cache_mask is a superset of
cpu_sibling_mask if and only if shared_caches is set.

Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200913171038.GB11808@linux.vnet.ibm.com
2020-09-16 22:13:31 +10:00
Srikar Dronamraju
3c6032a8fe powerpc/smp: Move topology fixups into a new function
Move topology fixup based on the platform attributes into its own
function which is called just before set_sched_topology.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200810071834.92514-5-srikar@linux.vnet.ibm.com
2020-09-16 22:13:31 +10:00
Srikar Dronamraju
5e93f16ae4 powerpc/smp: Move powerpc_topology above
Just moving the powerpc_topology description above.
This will help in using functions in this file and avoid declarations.

No other functional changes

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200810071834.92514-4-srikar@linux.vnet.ibm.com
2020-09-16 22:13:31 +10:00
Srikar Dronamraju
2ef0ca54d9 powerpc/smp: Merge Power9 topology with Power topology
A new sched_domain_topology_level was added just for Power9. However the
same can be achieved by merging powerpc_topology with power9_topology
and makes the code more simpler especially when adding a new sched
domain.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200810071834.92514-3-srikar@linux.vnet.ibm.com
2020-09-16 22:13:31 +10:00
Srikar Dronamraju
d0fd24bbd2 powerpc/smp: Fix a warning under !NEED_MULTIPLE_NODES
Fix a build warning in a non CONFIG_NEED_MULTIPLE_NODES
"error: _numa_cpu_lookup_table_ undeclared"

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200810071834.92514-2-srikar@linux.vnet.ibm.com
2020-09-16 22:13:30 +10:00
Srikar Dronamraju
e75130f20b powerpc/numa: Offline memoryless cpuless node 0
Currently Linux kernel with CONFIG_NUMA on a system with multiple
possible nodes, marks node 0 as online at boot.  However in practice,
there are systems which have node 0 as memoryless and cpuless.

This can cause numa_balancing to be enabled on systems with only one node
with memory and CPUs. The existence of this dummy node which is cpuless and
memoryless node can confuse users/scripts looking at output of lscpu /
numactl.

By marking, node 0 as offline, lets stop assuming that node 0 is
always online. If node 0 has CPU or memory that are online, node 0 will
again be set as online.

v5.8
 available: 2 nodes (0,2)
 node 0 cpus:
 node 0 size: 0 MB
 node 0 free: 0 MB
 node 2 cpus: 0 1 2 3 4 5 6 7
 node 2 size: 32625 MB
 node 2 free: 31490 MB
 node distances:
 node   0   2
   0:  10  20
   2:  20  10

proc and sys files
------------------
 /sys/devices/system/node/online:            0,2
 /proc/sys/kernel/numa_balancing:            1
 /sys/devices/system/node/has_cpu:           2
 /sys/devices/system/node/has_memory:        2
 /sys/devices/system/node/has_normal_memory: 2
 /sys/devices/system/node/possible:          0-31

v5.8 + patch
------------------
 available: 1 nodes (2)
 node 2 cpus: 0 1 2 3 4 5 6 7
 node 2 size: 32625 MB
 node 2 free: 31487 MB
 node distances:
 node   2
   2:  10

proc and sys files
------------------
/sys/devices/system/node/online:            2
/proc/sys/kernel/numa_balancing:            0
/sys/devices/system/node/has_cpu:           2
/sys/devices/system/node/has_memory:        2
/sys/devices/system/node/has_normal_memory: 2
/sys/devices/system/node/possible:          0-31

Example of a node with online CPUs/memory on node 0.
(Same o/p with and without patch)
numactl -H
available: 4 nodes (0-3)
node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
node 0 size: 32482 MB
node 0 free: 22994 MB
node 1 cpus: 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95
node 1 size: 0 MB
node 1 free: 0 MB
node 2 cpus: 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143
node 2 size: 0 MB
node 2 free: 0 MB
node 3 cpus: 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 node 3 size: 0 MB
node 3 free: 0 MB
node distances:
node   0   1   2   3
  0:  10  20  40  40
  1:  20  10  40  40
  2:  40  40  10  20
  3:  40  40  20  10

Note: On Powerpc, cpu_to_node of possible but not present cpus would
previously return 0. Hence this commit depends on commit ("powerpc/numa: Set
numa_node for all possible cpus") and commit ("powerpc/numa: Prefer node id
queried from vphn"). Without the 2 commits, Powerpc system might crash.

1. User space applications like Numactl, lscpu, that parse the sysfs tend to
believe there is an extra online node. This tends to confuse users and
applications. Other user space applications start believing that system was
not able to use all the resources (i.e missing resources) or the system was
not setup correctly.

2. Also existence of dummy node also leads to inconsistent information. The
number of online nodes is inconsistent with the information in the
device-tree and resource-dump

3. When the dummy node is present, single node non-Numa systems end up showing
up as NUMA systems and numa_balancing gets enabled. This will mean we take
the hit from the unnecessary numa hinting faults.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200818081104.57888-4-srikar@linux.vnet.ibm.com
2020-09-16 22:05:20 +10:00
Srikar Dronamraju
6398eaa268 powerpc/numa: Prefer node id queried from vphn
Node id queried from the static device tree may not
be correct. For example: it may always show 0 on a shared processor.
Hence prefer the node id queried from vphn and fallback on the device tree
based node id if vphn query fails.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200818081104.57888-3-srikar@linux.vnet.ibm.com
2020-09-16 22:05:19 +10:00
Srikar Dronamraju
a874f1005e powerpc/numa: Set numa_node for all possible cpus
A Powerpc system with multiple possible nodes and with CONFIG_NUMA
enabled always used to have a node 0, even if node 0 does not any cpus
or memory attached to it. As per PAPR, node affinity of a cpu is only
available once its present / online. For all cpus that are possible but
not present, cpu_to_node() would point to node 0.

To ensure a cpuless, memoryless dummy node is not online, powerpc need
to make sure all possible but not present cpu_to_node are set to a
proper node.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200818081104.57888-2-srikar@linux.vnet.ibm.com
2020-09-16 22:05:19 +10:00
Srikar Dronamraju
67df77845c powerpc/numa: Restrict possible nodes based on platform
As per draft LoPAPR (Revision 2.9_pre7), section B.5.3 "Run Time
Abstraction Services (RTAS) Node" available at:
  https://openpowerfoundation.org/wp-content/uploads/2020/07/LoPAR-20200611.pdf

... there are 2 device tree properties:

  "ibm,max-associativity-domains"
   which defines the maximum number of domains that the firmware i.e
   PowerVM can support.

and:

  "ibm,current-associativity-domains"
   which defines the maximum number of domains that the current
   platform can support.

The value of "ibm,max-associativity-domains" is always greater than or
equal to "ibm,current-associativity-domains" property. If the latter
property is not available, use "ibm,max-associativity-domain" as a
fallback. In this yet to be released LoPAPR, "ibm,current-associativity-domains"
is mentioned in page 833 / B.5.3 which is covered under under
"Appendix B. System Binding" section

Currently powerpc uses the "ibm,max-associativity-domains" property
while setting the possible number of nodes. This is currently set at
32. However the possible number of nodes for a platform may be
significantly less. Hence set the possible number of nodes based on
"ibm,current-associativity-domains" property.

Nathan Lynch had raised a valid concern that post LPM (Live Partition
Migration), a user could DLPAR add processors and memory after LPM
with "new" associativity properties:
  https://lore.kernel.org/linuxppc-dev/871rljfet9.fsf@linux.ibm.com/t/#u

He also pointed out that "ibm,max-associativity-domains" has the same
contents on all currently available PowerVM systems, unlike
"ibm,current-associativity-domains" and hence may be better able to
handle the new NUMA associativity properties.

However with the recent commit dbce456280 ("powerpc/numa: Limit
possible nodes to within num_possible_nodes"), all new NUMA
associativity properties are capped to initially set nr_node_ids.
Hence this commit should be safe with any new DLPAR add post LPM.

  $ lsprop /proc/device-tree/rtas/ibm,*associ*-domains
  /proc/device-tree/rtas/ibm,current-associativity-domains
  		 00000005 00000001 00000002 00000002 00000002 00000010
  /proc/device-tree/rtas/ibm,max-associativity-domains
  		 00000005 00000001 00000008 00000020 00000020 00000100

  $ cat /sys/devices/system/node/possible ##Before patch
  0-31

  $ cat /sys/devices/system/node/possible ##After patch
  0-1

Note the maximum nodes this platform can support is only 2 but the
possible nodes is set to 32.

This is important because lot of kernel and user space code allocate
structures for all possible nodes leading to a lot of memory that is
allocated but not used.

I ran a simple experiment to create and destroy 100 memory cgroups on
boot on a 8 node machine (Power8 Alpine).

Before patch:
  free -k at boot
                total        used        free      shared  buff/cache   available
  Mem:      523498176     4106816   518820608       22272      570752   516606720
  Swap:       4194240           0     4194240

  free -k after creating 100 memory cgroups
                total        used        free      shared  buff/cache   available
  Mem:      523498176     4628416   518246464       22336      623296   516058688
  Swap:       4194240           0     4194240

  free -k after destroying 100 memory cgroups
                total        used        free      shared  buff/cache   available
  Mem:      523498176     4697408   518173760       22400      627008   515987904
  Swap:       4194240           0     4194240

After patch:
  free -k at boot
                total        used        free      shared  buff/cache   available
  Mem:      523498176     3969472   518933888       22272      594816   516731776
  Swap:       4194240           0     4194240

  free -k after creating 100 memory cgroups
                total        used        free      shared  buff/cache   available
  Mem:      523498176     4181888   518676096       22208      640192   516496448
  Swap:       4194240           0     4194240

  free -k after destroying 100 memory cgroups
                total        used        free      shared  buff/cache   available
  Mem:      523498176     4232320   518619904       22272      645952   516443264
  Swap:       4194240           0     4194240

Observations:
  Fixed kernel takes 137344 kb (4106816-3969472) less to boot.
  Fixed kernel takes 309184 kb (4628416-4181888-137344) less to create 100 memcgs.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
[mpe: Reformat change log a bit for readability]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200817055257.110873-1-srikar@linux.vnet.ibm.com
2020-09-16 22:05:19 +10:00
Srikar Dronamraju
f3232321db powerpc/topology: Override cpu_smt_mask
On Power9, a pair of SMT4 cores can be presented by the firmware as a SMT8
core for backward compatibility reasons, with the fusion of two SMT4 cores.
Powerpc allows LPARs to be live migrated from Power8 to Power9.  Existing
software developed/configured for Power8, expects to see a SMT8 core.

In order to maintain userspace backward compatibility (with Power8 chips in
case of Power9) in enterprise Linux systems, the topology_sibling_cpumask
has to be set to SMT8 core.

cpu_smt_mask() should generally point to the cpu mask of the SMT4 core.
Hence override the default cpu_smt_mask() to be powerpc specific
allowing for better scheduling behaviour on Power.

schbench
(latency measured in usecs, so lesser is better)
Without patch                   With patch
Latency percentiles (usec)	Latency percentiles (usec)
	50.0000th: 34           	50.0000th: 38
	75.0000th: 47           	75.0000th: 52
	90.0000th: 54           	90.0000th: 60
	95.0000th: 57           	95.0000th: 64
	*99.0000th: 62          	*99.0000th: 72
	99.5000th: 65           	99.5000th: 75
	99.9000th: 76           	99.9000th: 3452
	min=0, max=9205         	min=0, max=9344

schbench (With Cede disabled)
Without patch                   With patch
Latency percentiles (usec) 	Latency percentiles (usec)
	50.0000th: 20           	50.0000th: 21
	75.0000th: 28           	75.0000th: 29
	90.0000th: 33           	90.0000th: 34
	95.0000th: 35           	95.0000th: 37
	*99.0000th: 40          	*99.0000th: 40
	99.5000th: 48           	99.5000th: 42
	99.9000th: 94           	99.9000th: 79
	min=0, max=791          	min=0, max=791

perf bench sched pipe
usec/ops : lesser is better
Without patch
  N           Min           Max        Median           Avg        Stddev
101      5.095113      5.595269      5.204842     5.2298776    0.10762713

5.10 - 5.15 : ##################################################   23% (24)
5.15 - 5.20 : #############################################        21% (22)
5.20 - 5.25 : ##################################################   23% (24)
5.25 - 5.30 : #########################                            11% (12)
5.30 - 5.35 : ##########                                            4% (5)
5.35 - 5.40 : ########                                              3% (4)
5.40 - 5.45 : ########                                              3% (4)
5.45 - 5.50 : ####                                                  1% (2)
5.50 - 5.55 : ##                                                    0% (1)
5.55 - 5.60 : ####                                                  1% (2)

With patch
  N           Min           Max        Median           Avg        Stddev
101      5.134675      8.524719      5.207658     5.2780985    0.34911969

5.1 - 5.5 : ##################################################   94% (95)
5.5 - 5.8 : ##                                                    3% (4)
5.8 - 6.2 :                                                       0% (1)
6.2 - 6.5 :
6.5 - 6.8 :
6.8 - 7.2 :
7.2 - 7.5 :
7.5 - 7.8 :
7.8 - 8.2 :
8.2 - 8.5 :

perf bench sched pipe (cede disabled)
usec/ops : lesser is better
Without patch
  N           Min           Max        Median           Avg        Stddev
101      7.884227     12.576538      7.956474     8.0170722    0.46159054

7.9 - 8.4 : ##################################################   99% (100)
8.4 - 8.8 :
8.8 - 9.3 :
9.3 - 9.8 :
9.8 - 10.2 :
10.2 - 10.7 :
10.7 - 11.2 :
11.2 - 11.6 :
11.6 - 12.1 :
12.1 - 12.6 :

With patch
  N           Min           Max        Median           Avg        Stddev
101      7.956021      8.217284      8.015615     8.0283866   0.049844967

7.96 - 7.98 : ######################                               12% (13)
7.98 - 8.01 : ##################################################   28% (29)
8.01 - 8.03 : ####################################                 20% (21)
8.03 - 8.06 : #########################                            14% (15)
8.06 - 8.09 : ######################                               12% (13)
8.09 - 8.11 : ######                                                3% (4)
8.11 - 8.14 : ###                                                   1% (2)
8.14 - 8.17 : ###                                                   1% (2)
8.17 - 8.19 :
8.19 - 8.22 : #                                                     0% (1)

Observations: With the patch, the initial run/iteration takes a slight
longer time. This can be attributed to the fact that now we pick a CPU
from a idle core which could be sleep mode. Once we remove the cede,
state the numbers improve in favour of the patch.

ebizzy:
transactions per second (higher is better)
without patch
  N           Min           Max        Median           Avg        Stddev
100       1018433       1304470       1193208     1182315.7     60018.733

1018433 - 1047037 : ######                                                3% (3)
1047037 - 1075640 : ########                                              4% (4)
1075640 - 1104244 : ########                                              4% (4)
1104244 - 1132848 : ###############                                       7% (7)
1132848 - 1161452 : ####################################                 17% (17)
1161452 - 1190055 : ##########################                           12% (12)
1190055 - 1218659 : #############################################        21% (21)
1218659 - 1247263 : ##################################################   23% (23)
1247263 - 1275866 : ########                                              4% (4)
1275866 - 1304470 : ########                                              4% (4)

with patch
  N           Min           Max        Median           Avg        Stddev
100        967014       1292938       1208819     1185281.8     69815.851

 967014 - 999606  : ##                                                    1% (1)
 999606 - 1032199 : ##                                                    1% (1)
1032199 - 1064791 : ############                                          6% (6)
1064791 - 1097384 : ##########                                            5% (5)
1097384 - 1129976 : ##################                                    9% (9)
1129976 - 1162568 : ####################                                 10% (10)
1162568 - 1195161 : ##########################                           13% (13)
1195161 - 1227753 : ############################################         22% (22)
1227753 - 1260346 : ##################################################   25% (25)
1260346 - 1292938 : ##############                                        7% (7)

Observations: Not much changes, ebizzy is not much impacted.

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200807074517.27957-2-srikar@linux.vnet.ibm.com
2020-09-16 22:05:19 +10:00
Vaibhav Jain
ca78ef2f08 powerpc/papr_scm: Fix warning triggered by perf_stats_show()
A warning is reported by the kernel in case perf_stats_show() returns
an error code. The warning is of the form below:

 papr_scm ibm,persistent-memory:ibm,pmemory@44100001:
 	  Failed to query performance stats, Err:-10
 dev_attr_show: perf_stats_show+0x0/0x1c0 [papr_scm] returned bad count
 fill_read_buffer: dev_attr_show+0x0/0xb0 returned bad count

On investigation it looks like that the compiler is silently
truncating the return value of drc_pmem_query_stats() from 'long' to
'int', since the variable used to store the return code 'rc' is an
'int'. This truncated value is then returned back as a 'ssize_t' back
from perf_stats_show() to 'dev_attr_show()' which thinks of it as a
large unsigned number and triggers this warning..

To fix this we update the type of variable 'rc' from 'int' to
'ssize_t' that prevents the compiler from truncating the return value
of drc_pmem_query_stats() and returning correct signed value back from
perf_stats_show().

Fixes: 2d02bf835e ("powerpc/papr_scm: Fetch nvdimm performance stats from PHYP")
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200912081451.66225-1-vaibhav@linux.ibm.com
2020-09-16 22:05:03 +10:00
Nicholas Piggin
a665eec0a2 powerpc/64s/radix: Fix mm_cpumask trimming race vs kthread_use_mm
Commit 0cef77c779 ("powerpc/64s/radix: flush remote CPUs out of
single-threaded mm_cpumask") added a mechanism to trim the mm_cpumask of
a process under certain conditions. One of the assumptions is that
mm_users would not be incremented via a reference outside the process
context with mmget_not_zero() then go on to kthread_use_mm() via that
reference.

That invariant was broken by io_uring code (see previous sparc64 fix),
but I'll point Fixes: to the original powerpc commit because we are
changing that assumption going forward, so this will make backports
match up.

Fix this by no longer relying on that assumption, but by having each CPU
check the mm is not being used, and clearing their own bit from the mask
only if it hasn't been switched-to by the time the IPI is processed.

This relies on commit 38cf307c1f ("mm: fix kthread_use_mm() vs TLB
invalidate") and ARCH_WANT_IRQS_OFF_ACTIVATE_MM to disable irqs over mm
switch sequences.

Fixes: 0cef77c779 ("powerpc/64s/radix: flush remote CPUs out of single-threaded mm_cpumask")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
Depends-on: 38cf307c1f ("mm: fix kthread_use_mm() vs TLB invalidate")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200914045219.3736466-5-npiggin@gmail.com
2020-09-16 12:24:37 +10:00
Nicholas Piggin
66acd46080 powerpc: select ARCH_WANT_IRQS_OFF_ACTIVATE_MM
powerpc uses IPIs in some situations to switch a kernel thread away
from a lazy tlb mm, which is subject to the TLB flushing race
described in the changelog introducing ARCH_WANT_IRQS_OFF_ACTIVATE_MM.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200914045219.3736466-3-npiggin@gmail.com
2020-09-16 12:24:37 +10:00
Cédric Le Goater
3a3181e16f powerpc/pci: unmap legacy INTx interrupts when a PHB is removed
When a passthrough IO adapter is removed from a pseries machine using
hash MMU and the XIVE interrupt mode, the POWER hypervisor expects the
guest OS to clear all page table entries related to the adapter. If
some are still present, the RTAS call which isolates the PCI slot
returns error 9001 "valid outstanding translations" and the removal of
the IO adapter fails. This is because when the PHBs are scanned, Linux
maps automatically the INTx interrupts in the Linux interrupt number
space but these are never removed.

To solve this problem, we introduce a PPC platform specific
pcibios_remove_bus() routine which clears all interrupt mappings when
the bus is removed. This also clears the associated page table entries
of the ESB pages when using XIVE.

For this purpose, we record the logical interrupt numbers of the
mapped interrupt under the PHB structure and let pcibios_remove_bus()
do the clean up.

Since some PCI adapters, like GPUs, use the "interrupt-map" property
to describe interrupt mappings other than the legacy INTx interrupts,
we can not restrict the size of the mapping array to PCI_NUM_INTX. The
number of interrupt mappings is computed from the "interrupt-map"
property and the mapping array is allocated accordingly.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200807101854.844619-1-clg@kaod.org
2020-09-15 22:13:39 +10:00
Nicholas Piggin
ffd2961bb4 powerpc/powernv/idle: add a basic stop 0-3 driver for POWER10
This driver does not restore stop > 3 state, so it limits itself
to states which do not lose full state or TB.

The POWER10 SPRs are sufficiently different from P9 that it seems
easier to split out the P10 code. The POWER10 deep sleep code
(e.g., the BHRB restore) has been taken out, but it can be re-added
when stop > 3 support is added.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Tested-by: Pratik Rajesh Sampat<psampat@linux.ibm.com>
Tested-by: Vaidyanathan Srinivasan <svaidy@linux.ibm.com>
Reviewed-by: Pratik Rajesh Sampat<psampat@linux.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819094700.493399-1-npiggin@gmail.com
2020-09-15 22:13:38 +10:00
Aneesh Kumar K.V
79b123cdf9 powerepc/book3s64/hash: Align start/end address correctly with bolt mapping
This ensures we don't do a partial mapping of memory. With nvdimm, when
creating namespaces with size not aligned to 16MB, the kernel ends up partially
mapping the pages. This can result in kernel adding multiple hash page table
entries for the same range. A new namespace will result in
create_section_mapping() with start and end overlapping an already existing
bolted hash page table entry.

commit: 6acd7d5ef2 ("libnvdimm/namespace: Enforce memremap_compat_align()")
made sure that we always create namespaces aligned to 16MB. But we can do
better by avoiding mapping pages that are not aligned. This helps to catch
access to these partially mapped pages early.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200907072539.67310-1-aneesh.kumar@linux.ibm.com
2020-09-15 22:13:38 +10:00
Jason Yan
bbc4f40b53 powerpc/ps3: make two symbols static
This addresses the following sparse warning:

arch/powerpc/platforms/ps3/spu.c:451:33: warning: symbol
'spu_management_ps3_ops' was not declared. Should it be static?
arch/powerpc/platforms/ps3/spu.c:592:28: warning: symbol
'spu_priv1_ps3_ops' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200911020121.1464585-1-yanaijie@huawei.com
2020-09-15 22:13:38 +10:00
Christophe Leroy
4c42dc5c69 powerpc/kasan: Fix CONFIG_KASAN_VMALLOC for 8xx
Before the commit identified below, pages tables allocation was
performed after the allocation of final shadow area for linear memory.
But that commit switched the order, leading to page tables being
already allocated at the time 8xx kasan_init_shadow_8M() is called.
Due to this, kasan_init_shadow_8M() doesn't map the needed
shadow entries because there are already page tables.

kasan_init_shadow_8M() installs huge PMD entries instead of page
tables. We could at that time free the page tables, but there is no
point in creating page tables that get freed before being used.

Only book3s/32 hash needs early allocation of page tables. For other
variants, we can keep the initial order and create remaining page
tables after the allocation of final shadow memory for linear mem.

Move back the allocation of shadow page tables for
CONFIG_KASAN_VMALLOC into kasan_init() after the loop which creates
final shadow memory for linear mem.

Fixes: 41ea93cf7b ("powerpc/kasan: Fix shadow pages allocation failure")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8ae4554357da4882612644a74387ae05525b2aaa.1599800716.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:37 +10:00
Christophe Leroy
2c637d2df4 powerpc/powermac: Fix low_sleep_handler with KUAP and KUEP
low_sleep_handler() has an hardcoded restore of segment registers
that doesn't take KUAP and KUEP into account.

Use head_32's load_segment_registers() routine instead.

Fixes: a68c31fc01 ("powerpc/32s: Implement Kernel Userspace Access Protection")
Fixes: 31ed2b13c4 ("powerpc/32s: Implement Kernel Userspace Execution Prevention.")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/21b05f7298c1b18f73e6e5b4cd5005aafa24b6da.1599820109.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:37 +10:00
Christophe Leroy
c83c192a6f powerpc/process: Remove useless #ifdef CONFIG_PPC_FPU
Add a stub for __giveup_fpu() when CONFIG_PPC_FPU is
not selected, as done for CONFIG_SPE and CONFIG_ALTIVEC.

This allows to remove some #ifdef CONFIG_PPC_FPU.

Also change one to IS_ENABLED().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/69c8b7954ceeccc6b849e52e1fa41b3a0f10f6c1.1597643221.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:36 +10:00
Christophe Leroy
532ed1900d powerpc/process: Remove useless #ifdef CONFIG_SPE
cpu_has_feature(CPU_FTR_SPE) returns false when CONFIG_SPE is
not set.

There is no need to enclose the test in an #ifdef CONFIG_SPE.
Remove it.

CPU_FTR_SPE only exists on 32 bits. Define it as 0 on 64 bits.

We have a couple of places like:

 #ifdef CONFIG_SPE
	if (cpu_has_feature(CPU_FTR_SPE)) {
		do_something_that_requires_CONFIG_SPE
	} else {
		return -EINVAL;
	}
 #else
	return -EINVAL;
 #endif

Replace them by a cleaner version:

	if (cpu_has_feature(CPU_FTR_SPE)) {
 #ifdef CONFIG_SPE
		do_something_that_requires_CONFIG_SPE
 #endif
	} else {
		return -EINVAL;
	}

When CONFIG_SPE is not set, this resolves to an unconditional
return of -EINVAL

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/698df8387555765b70ea42e4a7fa48141c309c1f.1597643221.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:36 +10:00
Christophe Leroy
e3667ee427 powerpc/process: Remove useless #ifdef CONFIG_ALTIVEC
cpu_has_feature(CPU_FTR_ALTIVEC) returns false when CONFIG_ALTIVEC is
not set.

There is no need to enclose the test in an #ifdef CONFIG_ALTIVEC.
Remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/03ba6b52344ca7c336df2bc6e3d31d736c804ae2.1597643221.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:36 +10:00
Christophe Leroy
80739c2bd2 powerpc/process: Remove useless #ifdef CONFIG_VSX
cpu_has_feature(CPU_FTR_VSX) returns false when CONFIG_VSX is
not set.

There is no need to enclose the test in an #ifdef CONFIG_VSX.
Remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0eb61cf0dc66d781d47deb2228498cd61d03a754.1597643221.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:35 +10:00
Christophe Leroy
60d62bfd24 powerpc/process: Tag an #endif to help locate the matching #ifdef.
That #endif is more than 100 lines after the matching #ifdef,
and there are several #ifdef/#else/#endif inbetween.

Tag it as /* CONFIG_PPC_BOOK3S_64 */ to help locate the
matching #ifdef.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3612a8f8aaca16de3fc414a7e66293319d6e213c.1597643147.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:35 +10:00
Christophe Leroy
8f020c7ca3 powerpc/process: Replace #ifdef CONFIG_KALLSYMS by IS_ENABLED()
The #ifdef CONFIG_KALLSYMS encloses some printk which can
compile in all cases.

Replace by IS_ENABLED().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2d89732a9062b2cf2651728804e4b8f6c9b9358e.1597643164.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:34 +10:00
Christophe Leroy
2ec42996f5 powerpc/process: Replace an #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) by IS_ENABLED()
The #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) encloses some
printk which can be compiled in all cases.

Replace by IS_ENABLED().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a1b6ef3d657c8f249193442f56868fc358ea5b6c.1597643160.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:34 +10:00
Christophe Leroy
bfac279930 powerpc/process: Replace an #ifdef CONFIG_PPC_BOOK3S_64 by IS_ENABLED()
This #ifdef CONFIG_PPC_BOOK3S_64 calls preload_new_slb_context()
when radix is not enabled.

radix_enabled() is always defined, and the prototype for
preload_new_slb_context() is always present, so the #ifdef
is unneeded.

Replace it by IS_ENABLED().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d31506ca9bac9def68cf7424eded63fdc4fb6660.1597643167.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:34 +10:00
Christophe Leroy
04d476bfbb powerpc/process: Replace an #ifdef CONFIG_PPC_47x by IS_ENABLED()
isync() is always defined, no need for an #ifdef.

Replace it by IS_ENABLED(CONFIG_PPC_47x).

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ac8da0e3baa91dda805e1e492fd65aecd90c1fb5.1597643156.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:33 +10:00
Christophe Leroy
da7bb43ab9 powerpc/32: Fix vmap stack - Properly set r1 before activating MMU
We need r1 to be properly set before activating MMU, otherwise any new
exception taken while saving registers into the stack in exception
prologs will use the user stack, which is wrong and will even lockup
or crash when KUAP is selected.

Do that by switching the meaning of r11 and r1 until we have saved r1
to the stack: copy r1 into r11 and setup the new stack pointer in r1.
To avoid complicating and impacting all generic and specific prolog
code (and more), copy back r1 into r11 once r11 is save onto
the stack.

We could get rid of copying r1 back and forth at the cost of
rewriting everything to use r1 instead of r11 all the way when
CONFIG_VMAP_STACK is set, but the effort is probably not worth it.

Fixes: 028474876f ("powerpc/32: prepare for CONFIG_VMAP_STACK")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8f85e8752ac5af602db7237ef53d634f4f3d3892.1599486108.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:33 +10:00
Christophe Leroy
c118c7303a powerpc/32: Fix vmap stack - Do not activate MMU before reading task struct
We need r1 to be properly set before activating MMU, so
reading task_struct->stack must be done with MMU off.

This means we need an additional register to play with MSR
bits while r11 now points to the stack. For that, move r10
back to CR (As is already done for hash MMU) and use r10.

We still don't have r1 correct yet when we activate MMU.
It is done in following patch.

Fixes: 028474876f ("powerpc/32: prepare for CONFIG_VMAP_STACK")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a027d447022a006c9c4958ac734128e577a3c5c1.1599486108.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:33 +10:00
Christophe Leroy
7fdf966bed powerpc/uaccess: Remove __put_user_asm() and __put_user_asm2()
__put_user_asm() and __put_user_asm2() are not used anymore.

Remove them.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d66c4a372738d2fbd81f433ca86e4295871ace6a.1599216721.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:32 +10:00
Christophe Leroy
e64ac41ab0 powerpc/uaccess: Switch __patch_instruction() to __put_user_asm_goto()
__patch_instruction() is the only user of __put_user_asm() outside
of asm/uaccess.h

Switch to the new __put_user_asm_goto() to enable retirement of
__put_user_asm() in a later patch.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b9745b122f4a9ae72cef445c61320022ab8b77b7.1599216721.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:32 +10:00
Christophe Leroy
ee0a49a687 powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()
__put_user_asm_goto() provides more flexibility to GCC and avoids using
a local variable to tell if the write succeeded or not.
GCC can then avoid implementing a cmp in the fast path.

See the difference for a small function like the PPC64 version of
save_general_regs() in arch/powerpc/kernel/signal_32.c:

Before the patch (unreachable nop removed):

0000000000000c10 <.save_general_regs>:
     c10:	39 20 00 2c 	li      r9,44
     c14:	39 40 00 00 	li      r10,0
     c18:	7d 29 03 a6 	mtctr   r9
     c1c:	38 c0 00 00 	li      r6,0
     c20:	48 00 00 14 	b       c34 <.save_general_regs+0x24>
     c30:	42 40 00 40 	bdz     c70 <.save_general_regs+0x60>
     c34:	28 2a 00 27 	cmpldi  r10,39
     c38:	7c c8 33 78 	mr      r8,r6
     c3c:	79 47 1f 24 	rldicr  r7,r10,3,60
     c40:	39 20 00 01 	li      r9,1
     c44:	41 82 00 0c 	beq     c50 <.save_general_regs+0x40>
     c48:	7d 23 38 2a 	ldx     r9,r3,r7
     c4c:	79 29 00 20 	clrldi  r9,r9,32
     c50:	91 24 00 00 	stw     r9,0(r4)
     c54:	2c 28 00 00 	cmpdi   r8,0
     c58:	39 4a 00 01 	addi    r10,r10,1
     c5c:	38 84 00 04 	addi    r4,r4,4
     c60:	41 82 ff d0 	beq     c30 <.save_general_regs+0x20>
     c64:	38 60 ff f2 	li      r3,-14
     c68:	4e 80 00 20 	blr
     c70:	38 60 00 00 	li      r3,0
     c74:	4e 80 00 20 	blr

0000000000000000 <.fixup>:
  cc:	39 00 ff f2 	li      r8,-14
  d0:	48 00 00 00 	b       d0 <.fixup+0xd0>
			d0: R_PPC64_REL24	.text+0xc54

After the patch:

0000000000001490 <.save_general_regs>:
    1490:	39 20 00 2c 	li      r9,44
    1494:	39 40 00 00 	li      r10,0
    1498:	7d 29 03 a6 	mtctr   r9
    149c:	60 00 00 00 	nop
    14a0:	28 2a 00 27 	cmpldi  r10,39
    14a4:	79 48 1f 24 	rldicr  r8,r10,3,60
    14a8:	39 20 00 01 	li      r9,1
    14ac:	41 82 00 0c 	beq     14b8 <.save_general_regs+0x28>
    14b0:	7d 23 40 2a 	ldx     r9,r3,r8
    14b4:	79 29 00 20 	clrldi  r9,r9,32
    14b8:	91 24 00 00 	stw     r9,0(r4)
    14bc:	39 4a 00 01 	addi    r10,r10,1
    14c0:	38 84 00 04 	addi    r4,r4,4
    14c4:	42 00 ff dc 	bdnz    14a0 <.save_general_regs+0x10>
    14c8:	38 60 00 00 	li      r3,0
    14cc:	4e 80 00 20 	blr
    14d0:	38 60 ff f2 	li      r3,-14
    14d4:	4e 80 00 20 	blr

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/94ba5a5138f99522e1562dbcdb38d31aa790dc89.1599216721.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:32 +10:00
Christophe Leroy
fcf1f26895 powerpc/uaccess: Add pre-update addressing to __put_user_asm_goto()
Enable pre-update addressing mode in __put_user_asm_goto()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/346f65d677adb11865f7762c25a1ca3c64404ba5.1599216023.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:31 +10:00
Christophe Leroy
e47168f3d1 powerpc/8xx: Support 16k hugepages with 4k pages
The 8xx has 4 page sizes: 4k, 16k, 512k and 8M

4k and 16k can be selected at build time as standard page sizes,
and 512k and 8M are hugepages.

When 4k standard pages are selected, 16k pages are not available.

Allow 16k pages as hugepages when 4k pages are used.

To allow that, implement arch_make_huge_pte() which receives
the necessary arguments to allow setting the PTE in accordance
with the page size:
- 512 k pages must have _PAGE_HUGE and _PAGE_SPS. They are set
by pte_mkhuge(). arch_make_huge_pte() does nothing.
- 16 k pages must have only _PAGE_SPS. arch_make_huge_pte() clears
_PAGE_HUGE.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a518abc29266a708dfbccc8fce9ae6694fe4c2c6.1598862623.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:31 +10:00
Christophe Leroy
175a999915 powerpc/8xx: Refactor calculation of number of entries per PTE in page tables
On 8xx, the number of entries occupied by a PTE in the page tables
depends on the size of the page. At the time being, this calculation
is done in two places: in pte_update() and in set_huge_pte_at()

Refactor this calculation into a helper called
number_of_cells_per_pte(). For the time being, the val param is
unused. It will be used by following patch.

Instead of opencoding is_hugepd(), use hugepd_ok() with a forward
declaration.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f6ea2483c2c389567b007945948f704d18cfaeea.1598862623.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:31 +10:00
Christophe Leroy
542db12a9c powerpc: Fix random segfault when freeing hugetlb range
The following random segfault is observed from time to time with
map_hugetlb selftest:

root@localhost:~# ./map_hugetlb 1 19
524288 kB hugepages
Mapping 1 Mbytes
Segmentation fault

[   31.219972] map_hugetlb[365]: segfault (11) at 117 nip 77974f8c lr 779a6834 code 1 in ld-2.23.so[77966000+21000]
[   31.220192] map_hugetlb[365]: code: 9421ffc0 480318d1 93410028 90010044 9361002c 93810030 93a10034 93c10038
[   31.220307] map_hugetlb[365]: code: 93e1003c 93210024 8123007c 81430038 <80e90004> 814a0004 7f443a14 813a0004
[   31.221911] BUG: Bad rss-counter state mm:(ptrval) type:MM_FILEPAGES val:33
[   31.229362] BUG: Bad rss-counter state mm:(ptrval) type:MM_ANONPAGES val:5

This fault is due to hugetlb_free_pgd_range() freeing page tables
that are also used by regular pages.

As explain in the comment at the beginning of
hugetlb_free_pgd_range(), the verification done in free_pgd_range()
on floor and ceiling is not done here, which means
hugetlb_free_pte_range() can free outside the expected range.

As the verification cannot be done in hugetlb_free_pgd_range(), it
must be done in hugetlb_free_pte_range().

Fixes: b250c8c08c ("powerpc/8xx: Manage 512k huge pages as standard pages.")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f0cb2a5477cd87d1eaadb128042e20aeb2bc2859.1598860677.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:30 +10:00
Finn Thain
e63d6fb563 powerpc/tau: Disable TAU between measurements
Enabling CONFIG_TAU_INT causes random crashes:

Unrecoverable exception 1700 at c0009414 (msr=1000)
Oops: Unrecoverable exception, sig: 6 [#1]
BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2 PowerMac
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-pmac-00043-gd5f545e1a8593 #5
NIP:  c0009414 LR: c0009414 CTR: c00116fc
REGS: c0799eb8 TRAP: 1700   Not tainted  (5.7.0-pmac-00043-gd5f545e1a8593)
MSR:  00001000 <ME>  CR: 22000228  XER: 00000100

GPR00: 00000000 c0799f70 c076e300 00800000 0291c0ac 00e00000 c076e300 00049032
GPR08: 00000001 c00116fc 00000000 dfbd3200 ffffffff 007f80a8 00000000 00000000
GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 c075ce04
GPR24: c075ce04 dfff8880 c07b0000 c075ce04 00080000 00000001 c079ef98 c079ef5c
NIP [c0009414] arch_cpu_idle+0x24/0x6c
LR [c0009414] arch_cpu_idle+0x24/0x6c
Call Trace:
[c0799f70] [00000001] 0x1 (unreliable)
[c0799f80] [c0060990] do_idle+0xd8/0x17c
[c0799fa0] [c0060ba4] cpu_startup_entry+0x20/0x28
[c0799fb0] [c072d220] start_kernel+0x434/0x44c
[c0799ff0] [00003860] 0x3860
Instruction dump:
XXXXXXXX XXXXXXXX XXXXXXXX 3d20c07b XXXXXXXX XXXXXXXX XXXXXXXX 7c0802a6
XXXXXXXX XXXXXXXX XXXXXXXX 4e800421 XXXXXXXX XXXXXXXX XXXXXXXX 7d2000a6
---[ end trace 3a0c9b5cb216db6b ]---

Resolve this problem by disabling each THRMn comparator when handling
the associated THRMn interrupt and by disabling the TAU entirely when
updating THRMn thresholds.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5a0ba3dc5612c7aac596727331284a3676c08472.1599260540.git.fthain@telegraphics.com.au
2020-09-15 22:13:30 +10:00
Finn Thain
5e3119e15f powerpc/tau: Check processor type before enabling TAU interrupt
According to Freescale's documentation, MPC74XX processors have an
erratum that prevents the TAU interrupt from working, so don't try to
use it when running on those processors.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c281611544768e758bd58fe812cf702a5bd2d042.1599260540.git.fthain@telegraphics.com.au
2020-09-15 22:13:28 +10:00
Finn Thain
420ab2bc75 powerpc/tau: Remove duplicated set_thresholds() call
The commentary at the call site seems to disagree with the code. The
conditional prevents calling set_thresholds() via the exception handler,
which appears to crash. Perhaps that's because it immediately triggers
another TAU exception. Anyway, calling set_thresholds() from TAUupdate()
is redundant because tau_timeout() does so.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d7c7ee33232cf72a6a6bbb6ef05838b2e2b113c0.1599260540.git.fthain@telegraphics.com.au
2020-09-15 22:13:27 +10:00
Finn Thain
b1c6a0a10b powerpc/tau: Convert from timer to workqueue
Since commit 19dbdcb803 ("smp: Warn on function calls from softirq
context") the Thermal Assist Unit driver causes a warning like the
following when CONFIG_SMP is enabled.

  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 0 at kernel/smp.c:428 smp_call_function_many_cond+0xf4/0x38c
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-pmac #3
  NIP:  c00b37a8 LR: c00b3abc CTR: c001218c
  REGS: c0799c60 TRAP: 0700   Not tainted  (5.7.0-pmac)
  MSR:  00029032 <EE,ME,IR,DR,RI>  CR: 42000224  XER: 00000000
  GPR00: c00b3abc c0799d18 c076e300 c079ef5c c0011fec 00000000 00000000 00000000
  GPR08: 00000100 00000100 00008000 ffffffff 42000224 00000000 c079d040 c079d044
  GPR16: 00000001 00000000 00000004 c0799da0 c079f054 c07a0000 c07a0000 00000000
  GPR24: c0011fec 00000000 c079ef5c c079ef5c 00000000 00000000 00000000 00000000
  NIP [c00b37a8] smp_call_function_many_cond+0xf4/0x38c
  LR [c00b3abc] on_each_cpu+0x38/0x68
  Call Trace:
  [c0799d18] [ffffffff] 0xffffffff (unreliable)
  [c0799d68] [c00b3abc] on_each_cpu+0x38/0x68
  [c0799d88] [c0096704] call_timer_fn.isra.26+0x20/0x7c
  [c0799d98] [c0096b40] run_timer_softirq+0x1d4/0x3fc
  [c0799df8] [c05b4368] __do_softirq+0x118/0x240
  [c0799e58] [c0039c44] irq_exit+0xc4/0xcc
  [c0799e68] [c000ade8] timer_interrupt+0x1b0/0x230
  [c0799ea8] [c0013520] ret_from_except+0x0/0x14
  --- interrupt: 901 at arch_cpu_idle+0x24/0x6c
      LR = arch_cpu_idle+0x24/0x6c
  [c0799f70] [00000001] 0x1 (unreliable)
  [c0799f80] [c0060990] do_idle+0xd8/0x17c
  [c0799fa0] [c0060ba8] cpu_startup_entry+0x24/0x28
  [c0799fb0] [c072d220] start_kernel+0x434/0x44c
  [c0799ff0] [00003860] 0x3860
  Instruction dump:
  8129f204 2f890000 40beff98 3d20c07a 8929eec4 2f890000 40beff88 0fe00000
  81220000 552805de 550802ef 4182ff84 <0fe00000> 3860ffff 7f65db78 7f44d378
  ---[ end trace 34a886e47819c2eb ]---

Don't call on_each_cpu() from a timer callback, call it from a worker
thread instead.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/bb61650bea4f4c91fb8e24b9a6f130a1438651a7.1599260540.git.fthain@telegraphics.com.au
2020-09-15 22:13:26 +10:00
Finn Thain
66943005cc powerpc/tau: Use appropriate temperature sample interval
According to the MPC750 Users Manual, the SITV value in Thermal
Management Register 3 is 13 bits long. The present code calculates the
SITV value as 60 * 500 cycles. This would overflow to give 10 us on
a 500 MHz CPU rather than the intended 60 us. (But according to the
Microprocessor Datasheet, there is also a factor of 266 that has to be
applied to this value on certain parts i.e. speed sort above 266 MHz.)
Always use the maximum cycle count, as recommended by the Datasheet.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/896f542e5f0f1d6cf8218524c2b67d79f3d69b3c.1599260540.git.fthain@telegraphics.com.au
2020-09-15 22:13:24 +10:00
Aneesh Kumar K.V
b32d5d7e92 powerpc/mm/book3s: Split radix and hash MAX_PHYSMEM limit
MAX_PHYSMEM #define is used along with sparsemem to determine the SECTION_SHIFT
value. Powerpc also uses the same value to limit the max memory enabled on the
system. With 4K PAGE_SIZE and hash translation mode, we want to limit the max
memory enabled to 64TB due to page table size restrictions. However, with
radix translation, we don't have these restrictions. Hence split the radix
and hash MA_PHYSMEM limit and use different limit for each of them.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200608070904.387440-4-aneesh.kumar@linux.ibm.com
2020-09-15 22:13:22 +10:00
Aneesh Kumar K.V
7746406baa powerpc/book3s64/hash/4k: Support large linear mapping range with 4K
With commit: 0034d395f8 ("powerpc/mm/hash64: Map all the kernel
regions in the same 0xc range"), we now split the 64TB address range
into 4 contexts each of 16TB. That implies we can do only 16TB linear
mapping.

On some systems, eg. Power9, memory attached to nodes > 0 will appear
above 16TB in the linear mapping. This resulted in kernel crash when
we boot such systems in hash translation mode with 4K PAGE_SIZE.

This patch updates the kernel mapping such that we now start supporting upto
61TB of memory with 4K. The kernel mapping now looks like below 4K PAGE_SIZE
and hash translation.

    vmalloc start     = 0xc0003d0000000000
    IO start          = 0xc0003e0000000000
    vmemmap start     = 0xc0003f0000000000

Our MAX_PHYSMEM_BITS for 4K is still 64TB even though we can only map 61TB.
We prevent bolt mapping anything outside 61TB range by checking against
H_VMALLOC_START.

Fixes: 0034d395f8 ("powerpc/mm/hash64: Map all the kernel regions in the same 0xc range")
Reported-by: Cameron Berkenpas <cam@neo-zeon.de>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200608070904.387440-3-aneesh.kumar@linux.ibm.com
2020-09-15 22:13:22 +10:00
Aneesh Kumar K.V
eb553f1697 powerpc/64/mm: implement page mapping percpu first chunk allocator
Implement page mapping percpu first chunk allocator as a fallback to
the embedding allocator. With 4K hash translation we limit our page
table range to 64TB and commit: 0034d395f8 ("powerpc/mm/hash64: Map all the
kernel regions in the same 0xc range") moved all kernel mapping to
that 64TB range. In-order to support sparse memory layout we need
to increase our linear mapping space and reduce other mappings.

With such a layout percpu embedded first chunk allocator will fail
because of small vmalloc range. Add a fallback to page mapping
percpu first chunk allocator for such failures.

The below dmesg output can be observed in such case.

 percpu: max_distance=0x1ffffef00000 too large for vmalloc space 0x10000000000
 PERCPU: auto allocator failed (-22), falling back to page size
 percpu: 40 4K pages/cpu s148816 r0 d15024

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200608070904.387440-2-aneesh.kumar@linux.ibm.com
2020-09-15 22:13:22 +10:00
Aneesh Kumar K.V
2a32abac88 powerpc/percpu: Update percpu bootmem allocator
This update the ppc64 version to be closer to x86/sparc.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200608070904.387440-1-aneesh.kumar@linux.ibm.com
2020-09-15 22:13:21 +10:00
Ravi Bangoria
fa725cc53d powerpc/watchpoint/ptrace: Introduce PPC_DEBUG_FEATURE_DATA_BP_ARCH_31
PPC_DEBUG_FEATURE_DATA_BP_ARCH_31 can be used to determine whether
we are running on an ISA 3.1 compliant machine. Which is needed to
determine DAR behaviour, 512 byte boundary limit etc. This was
requested by Pedro Miraglia Franco de Carvalho for extending
watchpoint features in gdb. Note that availability of 2nd DAWR is
independent of this flag and should be checked using
ppc_debug_info->num_data_bps.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-8-ravi.bangoria@linux.ibm.com
2020-09-15 22:13:20 +10:00
Ravi Bangoria
58da5984d2 powerpc/watchpoint: Add hw_len wherever missing
There are couple of places where we set len but not hw_len. For
ptrace/perf watchpoints, when CONFIG_HAVE_HW_BREAKPOINT=Y, hw_len
will be calculated and set internally while parsing watchpoint.
But when CONFIG_HAVE_HW_BREAKPOINT=N, we need to manually set
'hw_len'. Similarly for xmon as well, hw_len needs to be set
directly.

Fixes: b57aeab811 ("powerpc/watchpoint: Fix length calculation for unaligned target")
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-7-ravi.bangoria@linux.ibm.com
2020-09-15 22:13:20 +10:00
Ravi Bangoria
5b905d7798 powerpc/watchpoint: Fix exception handling for CONFIG_HAVE_HW_BREAKPOINT=N
On powerpc, ptrace watchpoint works in one-shot mode. i.e. kernel
disables event every time it fires and user has to re-enable it.
Also, in case of ptrace watchpoint, kernel notifies ptrace user
before executing instruction.

With CONFIG_HAVE_HW_BREAKPOINT=N, kernel is missing to disable
ptrace event and thus it's causing infinite loop of exceptions.
This is especially harmful when user watches on a data which is
also read/written by kernel, eg syscall parameters. In such case,
infinite exceptions happens in kernel mode which causes soft-lockup.

Fixes: 9422de3e95 ("powerpc: Hardware breakpoints rewrite to handle non DABR breakpoint registers")
Reported-by: Pedro Miraglia Franco de Carvalho <pedromfc@linux.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-6-ravi.bangoria@linux.ibm.com
2020-09-15 22:13:20 +10:00
Ravi Bangoria
edc8dd99b2 powerpc/watchpoint: Move DAWR detection logic outside of hw_breakpoint.c
Power10 hw has multiple DAWRs but hw doesn't tell which DAWR caused
the exception. So we have a sw logic to detect that in hw_breakpoint.c.
But hw_breakpoint.c gets compiled only with CONFIG_HAVE_HW_BREAKPOINT=Y.
Move DAWR detection logic outside of hw_breakpoint.c so that it can be
reused when CONFIG_HAVE_HW_BREAKPOINT is not set.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-5-ravi.bangoria@linux.ibm.com
2020-09-15 22:13:19 +10:00
Ravi Bangoria
9b6b7c680c powerpc/watchpoint/ptrace: Fix SETHWDEBUG when CONFIG_HAVE_HW_BREAKPOINT=N
When kernel is compiled with CONFIG_HAVE_HW_BREAKPOINT=N, user can
still create watchpoint using PPC_PTRACE_SETHWDEBUG, with limited
functionalities. But, such watchpoints are never firing because of
the missing privilege settings. Fix that.

It's safe to set HW_BRK_TYPE_PRIV_ALL because we don't really leak
any kernel address in signal info. Setting HW_BRK_TYPE_PRIV_ALL will
also help to find scenarios when kernel accesses user memory.

Reported-by: Pedro Miraglia Franco de Carvalho <pedromfc@linux.ibm.com>
Suggested-by: Pedro Miraglia Franco de Carvalho <pedromfc@linux.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-4-ravi.bangoria@linux.ibm.com
2020-09-15 22:13:18 +10:00
Ravi Bangoria
4441eb0233 powerpc/watchpoint: Fix handling of vector instructions
Vector load/store instructions are special because they are always
aligned. Thus unaligned EA needs to be aligned down before comparing
it with watch ranges. Otherwise we might consider valid event as
invalid.

Fixes: 74c6881019 ("powerpc/watchpoint: Prepare handler to handle more than one watchpoint")
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-3-ravi.bangoria@linux.ibm.com
2020-09-15 22:13:18 +10:00
Ravi Bangoria
4759c11ed2 powerpc/watchpoint: Fix quadword instruction handling on p10 predecessors
On p10 predecessors, watchpoint with quadword access is compared at
quadword length. If the watch range is doubleword or less than that
in a first half of quadword aligned 16 bytes, and if there is any
unaligned quadword access which will access only the 2nd half, the
handler should consider it as extraneous and emulate/single-step it
before continuing.

Fixes: 74c6881019 ("powerpc/watchpoint: Prepare handler to handle more than one watchpoint")
Reported-by: Pedro Miraglia Franco de Carvalho <pedromfc@linux.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-2-ravi.bangoria@linux.ibm.com
2020-09-15 22:12:25 +10:00
Linus Torvalds
973c096f6a vgacon: remove software scrollback support
Yunhai Zhang recently fixed a VGA software scrollback bug in commit
ebfdfeeae8 ("vgacon: Fix for missing check in scrollback handling"),
but that then made people look more closely at some of this code, and
there were more problems on the vgacon side, but also the fbcon software
scrollback.

We don't really have anybody who maintains this code - probably because
nobody actually _uses_ it any more.  Sure, people still use both VGA and
the framebuffer consoles, but they are no longer the main user
interfaces to the kernel, and haven't been for decades, so these kinds
of extra features end up bitrotting and not really being used.

So rather than try to maintain a likely unused set of code, I'll just
aggressively remove it, and see if anybody even notices.  Maybe there
are people who haven't jumped on the whole GUI badnwagon yet, and think
it's just a fad.  And maybe those people use the scrollback code.

If that turns out to be the case, we can resurrect this again, once
we've found the sucker^Wmaintainer for it who actually uses it.

Reported-by: NopNop Nop <nopitydays@gmail.com>
Tested-by: Willy Tarreau <w@1wt.eu>
Cc: 张云海 <zhangyunhai@nsfocus.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-14 10:06:15 -07:00
Thiago Jung Bauermann
eae9eec476 powerpc/pseries/svm: Allocate SWIOTLB buffer anywhere in memory
POWER secure guests (i.e., guests which use the Protected Execution
Facility) need to use SWIOTLB to be able to do I/O with the
hypervisor, but they don't need the SWIOTLB memory to be in low
addresses since the hypervisor doesn't have any addressing limitation.

This solves a SWIOTLB initialization problem we are seeing in secure
guests with 128 GB of RAM: they are configured with 4 GB of
crashkernel reserved memory, which leaves no space for SWIOTLB in low
addresses.

To do this, we use mostly the same code as swiotlb_init(), but
allocate the buffer using memblock_alloc() instead of
memblock_alloc_low().

Fixes: 2efbc58f15 ("powerpc/pseries/svm: Force SWIOTLB for secure guests")
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200818221126.391073-1-bauerman@linux.ibm.com
2020-09-14 23:07:14 +10:00
Michael Ellerman
231b232df8 powerpc/64: Make VDSO32 track COMPAT on 64-bit
When we added the VDSO32 kconfig symbol, which controls building of
the 32-bit VDSO, we made it depend on CPU_BIG_ENDIAN (for 64-bit).

That was because back then COMPAT was always enabled for 64-bit, so
depending on it would have left the 32-bit VDSO always enabled, which
we didn't want.

But since then we have made COMPAT selectable, and off by default for
ppc64le, so VDSO32 should really depend on that.

For most people this makes no difference, none of the defconfigs
change, it's only if someone is building ppc64le with COMPAT=y, they
will now also get VDSO32. If they've enabled COMPAT in order to run
32-bit binaries they presumably also want the 32-bit VDSO.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/20200908125850.407939-1-mpe@ellerman.id.au
2020-09-14 23:07:04 +10:00
Michael Ellerman
960e370813 Merge branch 'fixes' into next
Bring in our fixes branch for this cycle which avoids some small
conflicts with upcoming commits.
2020-09-14 22:57:18 +10:00
Christoph Hellwig
5ceda74093 dma-direct: rename and cleanup __phys_to_dma
The __phys_to_dma vs phys_to_dma distinction isn't exactly obvious.  Try
to improve the situation by renaming __phys_to_dma to
phys_to_dma_unencryped, and not forcing architectures that want to
override phys_to_dma to actually provide __phys_to_dma.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2020-09-11 09:14:43 +02:00
Christoph Hellwig
7bc5c428a6 dma-direct: remove __dma_to_phys
There is no harm in just always clearing the SME encryption bit, while
significantly simplifying the interface.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2020-09-11 09:14:25 +02:00
Vaibhav Jain
0460534b53 powerpc/papr_scm: Limit the readability of 'perf_stats' sysfs attribute
The newly introduced 'perf_stats' attribute uses the default access
mode of 0444, allowing non-root users to access performance stats of
an nvdimm and potentially force the kernel into issuing a large number
of expensive hypercalls. Since the information exposed by this
attribute cannot be cached it is better to ward off access to this
attribute from users who don't need to access to these performance
statistics.

Hence update the access mode of 'perf_stats' attribute to be only
readable by root users.

Fixes: 2d02bf835e ("powerpc/papr_scm: Fetch nvdimm performance stats from PHYP")
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200907110540.21349-1-vaibhav@linux.ibm.com
2020-09-09 14:44:38 +10:00
Christoph Hellwig
5ae4998b5d powerpc: remove address space overrides using set_fs()
Stop providing the possibility to override the address space using
set_fs() now that there is no need for that any more.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-08 22:21:37 -04:00
Christoph Hellwig
c331652534 powerpc: use non-set_fs based maccess routines
Provide __get_kernel_nofault and __put_kernel_nofault routines to
implement the maccess routines without messing with set_fs and without
opening up access to user space.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-08 22:21:36 -04:00
Christoph Hellwig
5e6e9852d6 uaccess: add infrastructure for kernel builds with set_fs()
Add a CONFIG_SET_FS option that is selected by architecturess that
implement set_fs, which is all of them initially.  If the option is not
set stubs for routines related to overriding the address space are
provided so that architectures can start to opt out of providing set_fs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-08 22:21:32 -04:00
Nicholas Piggin
dc462267d2 powerpc/64s: handle ISA v3.1 local copy-paste context switches
The ISA v3.1 the copy-paste facility has a new memory move functionality
which allows the copy buffer to be pasted to domestic memory (RAM) as
opposed to foreign memory (accelerator).

This means the POWER9 trick of avoiding the cp_abort on context switch if
the process had not mapped foreign memory does not work on POWER10. Do the
cp_abort unconditionally there.

KVM must also cp_abort on guest exit to prevent copy buffer state leaking
between contexts.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200825075535.224536-1-npiggin@gmail.com
2020-09-08 22:57:12 +10:00
Joel Stanley
a02f6d4235 powerpc: Warn about use of smt_snooze_delay
It's not done anything for a long time. Save the percpu variable, and
emit a warning to remind users to not expect it to do anything.

This uses pr_warn_once instead of pr_warn_ratelimit as testing
'ppc64_cpu --smt=off' on a 24 core / 4 SMT system showed the warning
to be noisy, as the online/offline loop is slow.

Fixes: 3fa8cad82b ("powerpc/pseries/cpuidle: smt-snooze-delay cleanup.")
Cc: stable@vger.kernel.org # v3.14
Signed-off-by: Joel Stanley <joel@jms.id.au>
Acked-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902000012.3440389-1-joel@jms.id.au
2020-09-08 22:57:12 +10:00
Joel Stanley
8f55984f53 powerpc/powernv: Print helpful message when cores guarded
Often the firmware will guard out cores after a crash. This often
undesirable, and is not immediately noticeable.

This adds an informative message when a CPU device tree nodes are
marked bad in the device tree.

Signed-off-by: Joel Stanley <joel@jms.id.au>
[mpe: Use an eye-catcher that's less likely to get us in trouble]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190801051630.5804-1-joel@jms.id.au
2020-09-08 22:57:11 +10:00
Leonardo Bras
8c0d51592f powerpc/pseries/iommu: Allow bigger 64bit window by removing default DMA window
On LoPAR "DMA Window Manipulation Calls", it's recommended to remove the
default DMA window for the device, before attempting to configure a DDW,
in order to make the maximum resources available for the next DDW to be
created.

This is a requirement for using DDW on devices in which hypervisor
allows only one DMA window.

If setting up a new DDW fails anywhere after the removal of this
default DMA window, it's needed to restore the default DMA window.
For this, an implementation of ibm,reset-pe-dma-windows rtas call is
needed:

Platforms supporting the DDW option starting with LoPAR level 2.7 implement
ibm,ddw-extensions. The first extension available (index 2) carries the
token for ibm,reset-pe-dma-windows rtas call, which is used to restore
the default DMA window for a device, if it has been deleted.

It does so by resetting the TCE table allocation for the PE to it's
boot time value, available in "ibm,dma-window" device tree node.

Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Tested-by: David Dai <zdai@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200805030455.123024-5-leobras.c@gmail.com
2020-09-08 22:57:11 +10:00
Leonardo Bras
74d0b3994e powerpc/pseries/iommu: Move window-removing part of remove_ddw into remove_dma_window
Move the window-removing part of remove_ddw into a new function
(remove_dma_window), so it can be used to remove other DMA windows.

It's useful for removing DMA windows that don't create DIRECT64_PROPNAME
property, like the default DMA window from the device, which uses
"ibm,dma-window".

Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Tested-by: David Dai <zdai@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200805030455.123024-4-leobras.c@gmail.com
2020-09-08 22:57:11 +10:00
Leonardo Bras
80f0251231 powerpc/pseries/iommu: Update call to ibm, query-pe-dma-windows
>From LoPAR level 2.8, "ibm,ddw-extensions" index 3 can make the number of
outputs from "ibm,query-pe-dma-windows" go from 5 to 6.

This change of output size is meant to expand the address size of
largest_available_block PE TCE from 32-bit to 64-bit, which ends up
shifting page_size and migration_capable.

This ends up requiring the update of
ddw_query_response->largest_available_block from u32 to u64, and manually
assigning the values from the buffer into this struct, according to
output size.

Also, a routine was created for helping reading the ddw extensions as
suggested by LoPAR: First reading the size of the extension array from
index 0, checking if the property exists, and then returning it's value.

Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Tested-by: David Dai <zdai@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200805030455.123024-3-leobras.c@gmail.com
2020-09-08 22:57:11 +10:00
Leonardo Bras
cac3e62908 powerpc/pseries/iommu: Create defines for operations in ibm, ddw-applicable
Create defines to help handling ibm,ddw-applicable values, avoiding
confusion about the index of given operations.

Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Tested-by: David Dai <zdai@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200805030455.123024-2-leobras.c@gmail.com
2020-09-08 22:57:11 +10:00
Russell Currey
0fb4871bcc powerpc/tools: Remove 90 line limit in checkpatch script
As of commit bdc48fa11e, scripts/checkpatch.pl now has a default line
length warning of 100 characters.  The powerpc wrapper script was using
a length of 90 instead of 80 in order to make checkpatch less
restrictive, but now it's making it more restrictive instead.

I think it makes sense to just use the default value now.

Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200828020542.393022-1-ruscur@russell.cc
2020-09-08 22:57:11 +10:00
Jordan Niethe
364b236a0b powerpc/boot: Update Makefile comment for 64bit wrapper
As of commit 147c05168f ("powerpc/boot: Add support for 64bit little
endian wrapper") the comment in the Makefile is misleading. The wrapper
packaging 64bit kernel may built as a 32 or 64 bit elf. Update the
comment to reflect this.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200825035147.3239-1-jniethe5@gmail.com
2020-09-08 22:24:19 +10:00
Michael Ellerman
529d2bd56a powerpc/64: Remove unused generic_secondary_thread_init()
The last caller was removed in 2014 in commit fb5a515704 ("powerpc:
Remove platforms/wsp and associated pieces").

As Jordan noticed even though there are no callers, the code above in
fsl_secondary_thread_init() falls through into
generic_secondary_thread_init(). So we can remove the _GLOBAL but not
the body of the function.

However because fsl_secondary_thread_init() is inside #ifdef
CONFIG_PPC_BOOK3E, we can never reach the body of
generic_secondary_thread_init() unless CONFIG_PPC_BOOK3E is enabled,
so we can wrap the whole thing in a single #ifdef.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015704.1976364-1-mpe@ellerman.id.au
2020-09-08 22:24:17 +10:00
Oliver O'Halloran
10bf59d923 powerpc/pseries/eeh: Fix dumb linebreaks
These annoy me every time I see them. Why are they here? They're not even
needed for 80cols compliance.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200818044557.135497-1-oohall@gmail.com
2020-09-08 22:23:42 +10:00
Christophe Leroy
353bce211e powerpc/process: Remove unnecessary #ifdef CONFIG_FUNCTION_GRAPH_TRACER
ftrace_graph_ret_addr() is always defined and returns 'ip' when
CONFIG_FUNCTION GRAPH_TRACER is not set.

So the #ifdef is not needed, remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/9d11143d4e27ba8274369a926968756917584868.1597643153.git.christophe.leroy@csgroup.eu
2020-09-08 22:23:42 +10:00
Christophe Leroy
2f279eeb68 powerpc/uaccess: Add pre-update addressing to __get_user_asm() and __put_user_asm()
Enable pre-update addressing mode in __get_user_asm() and __put_user_asm()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/13041c7df39e89ddf574ea0cdc6dedfdd9734140.1597235091.git.christophe.leroy@csgroup.eu
2020-09-08 22:23:22 +10:00
Masami Hiramatsu
b6c5a58dd8 powerpc: kprobes: Use generic kretprobe trampoline handler
Use the generic kretprobe trampoline handler. Don't use
framepointer verification.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/159870610825.1229682.2090635992093223399.stgit@devnote2
2020-09-08 11:52:34 +02:00
Alexey Kardashevskiy
437ef802e0 powerpc/dma: Fix dma_map_ops::get_required_mask
There are 2 problems with it:
  1. "<" vs expected "<<"
  2. the shift number is an IOMMU page number mask, not an address
  mask as the IOMMU page shift is missing.

This did not hit us before f1565c24b5 ("powerpc: use the generic
dma_ops_bypass mode") because we had additional code to handle bypass
mask so this chunk (almost?) never executed.However there were
reports that aacraid does not work with "iommu=nobypass".

After f1565c24b5, aacraid (and probably others which call
dma_get_required_mask() before setting the mask) was unable to enable
64bit DMA and fall back to using IOMMU which was known not to work,
one of the problems is double free of an IOMMU page.

This fixes DMA for aacraid, both with and without "iommu=nobypass" in
the kernel command line. Verified with "stress-ng -d 4".

Fixes: 6a5c7be5e4 ("powerpc: Override dma_get_required_mask by platform hook and ops")
Cc: stable@vger.kernel.org # v3.2+
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200908015106.79661-1-aik@ozlabs.ru
2020-09-08 14:20:55 +10:00
Masahiro Yamada
887af6d7c9 arch: vdso: add vdso linker script to 'targets' instead of extra-y
The vdso linker script is preprocessed on demand.
Adding it to 'targets' is enough to include the .cmd file.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Greentime Hu <green.hu@gmail.com>
2020-09-07 21:41:27 +09:00
Herbert Xu
d08d387b73 crypto: powerpc/crc-vpmsum_test - Fix sparse endianness warning
This patch fixes a sparse endianness warning by changing crc32 to
__le32 instead of u32:

  CHECK   ../arch/powerpc/crypto/crc-vpmsum_test.c
../arch/powerpc/crypto/crc-vpmsum_test.c:102:39: warning: cast from restricted __le32

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-09-04 17:57:15 +10:00
Nicolin Chen
1e9d90dbed dma-mapping: introduce dma_get_seg_boundary_nr_pages()
We found that callers of dma_get_seg_boundary mostly do an ALIGN
with page mask and then do a page shift to get number of pages:
    ALIGN(boundary + 1, 1 << shift) >> shift

However, the boundary might be as large as ULONG_MAX, which means
that a device has no specific boundary limit. So either "+ 1" or
passing it to ALIGN() would potentially overflow.

According to kernel defines:
    #define ALIGN_MASK(x, mask) (((x) + (mask)) & ~(mask))
    #define ALIGN(x, a)	ALIGN_MASK(x, (typeof(x))(a) - 1)

We can simplify the logic here into a helper function doing:
  ALIGN(boundary + 1, 1 << shift) >> shift
= ALIGN_MASK(b + 1, (1 << s) - 1) >> s
= {[b + 1 + (1 << s) - 1] & ~[(1 << s) - 1]} >> s
= [b + 1 + (1 << s) - 1] >> s
= [b + (1 << s)] >> s
= (b >> s) + 1

This patch introduces and applies dma_get_seg_boundary_nr_pages()
as an overflow-free helper for the dma_get_seg_boundary() callers
to get numbers of pages. It also takes care of the NULL dev case
for non-DMA API callers.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Acked-by: Niklas Schnelle <schnelle@linux.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-09-03 18:12:15 +02:00
Michael Ellerman
4c62285439 Revert "powerpc/build: vdso linker warning for orphan sections"
This reverts commit f2af201002.

It added a usage of cc-ldoption, but cc-ldoption was removed in commit
055efab312 ("kbuild: drop support for cc-ldoption").

Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2020-09-03 15:42:26 +10:00
Greg Kurz
5706d14d2a KVM: PPC: Book3S HV: XICS: Replace the 'destroy' method by a 'release' method
Similarly to what was done with XICS-on-XIVE and XIVE native KVM devices
with commit 5422e95103 ("KVM: PPC: Book3S HV: XIVE: Replace the 'destroy'
method by a 'release' method"), convert the historical XICS KVM device to
implement the 'release' method. This is needed to run nested guests with
an in-kernel IRQ chip. A typical POWER9 guest can select XICS or XIVE
during boot, which requires to be able to destroy and to re-create the
KVM device. Only the historical XICS KVM device is available under pseries
at the current time and it still uses the legacy 'destroy' method.

Switching to 'release' means that vCPUs might still be running when the
device is destroyed. In order to avoid potential use-after-free, the
kvmppc_xics structure is allocated on first usage and kept around until
the VM exits. The same pointer is used each time a KVM XICS device is
being created, but this is okay since we only have one per VM.

Clear the ICP of each vCPU with vcpu->mutex held. This ensures that the
next time the vCPU resumes execution, it won't be going into the XICS
code anymore.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-09-03 14:12:48 +10:00
Aneesh Kumar K.V
675bceb097 powerpc/mm: Remove DEBUG_VM_PGTABLE support on powerpc
The test is broken w.r.t page table update rules and results in kernel
crash as below. Disable the support until we get the tests updated.

[   21.083519] kernel BUG at arch/powerpc/mm/pgtable.c:304!
cpu 0x0: Vector: 700 (Program Check) at [c000000c6d1e76c0]
    pc: c00000000009a5ec: assert_pte_locked+0x14c/0x380
    lr: c0000000005eeeec: pte_update+0x11c/0x190
    sp: c000000c6d1e7950
   msr: 8000000002029033
  current = 0xc000000c6d172c80
  paca    = 0xc000000003ba0000   irqmask: 0x03   irq_happened: 0x01
    pid   = 1, comm = swapper/0
kernel BUG at arch/powerpc/mm/pgtable.c:304!
[link register   ] c0000000005eeeec pte_update+0x11c/0x190
[c000000c6d1e7950] 0000000000000001 (unreliable)
[c000000c6d1e79b0] c0000000005eee14 pte_update+0x44/0x190
[c000000c6d1e7a10] c000000001a2ca9c pte_advanced_tests+0x160/0x3d8
[c000000c6d1e7ab0] c000000001a2d4fc debug_vm_pgtable+0x7e8/0x1338
[c000000c6d1e7ba0] c0000000000116ec do_one_initcall+0xac/0x5f0
[c000000c6d1e7c80] c0000000019e4fac kernel_init_freeable+0x4dc/0x5a4
[c000000c6d1e7db0] c000000000012474 kernel_init+0x24/0x160
[c000000c6d1e7e20] c00000000000cbd0 ret_from_kernel_thread+0x5c/0x6c

With DEBUG_VM disabled

[   20.530152] BUG: Kernel NULL pointer dereference on read at 0x00000000
[   20.530183] Faulting instruction address: 0xc0000000000df330
cpu 0x33: Vector: 380 (Data SLB Access) at [c000000c6d19f700]
    pc: c0000000000df330: memset+0x68/0x104
    lr: c00000000009f6d8: hash__pmdp_huge_get_and_clear+0xe8/0x1b0
    sp: c000000c6d19f990
   msr: 8000000002009033
   dar: 0
  current = 0xc000000c6d177480
  paca    = 0xc00000001ec4f400   irqmask: 0x03   irq_happened: 0x01
    pid   = 1, comm = swapper/0
[link register   ] c00000000009f6d8 hash__pmdp_huge_get_and_clear+0xe8/0x1b0
[c000000c6d19f990] c00000000009f748 hash__pmdp_huge_get_and_clear+0x158/0x1b0 (unreliable)
[c000000c6d19fa10] c0000000019ebf30 pmd_advanced_tests+0x1f0/0x378
[c000000c6d19fab0] c0000000019ed088 debug_vm_pgtable+0x79c/0x1244
[c000000c6d19fba0] c0000000000116ec do_one_initcall+0xac/0x5f0
[c000000c6d19fc80] c0000000019a4fac kernel_init_freeable+0x4dc/0x5a4
[c000000c6d19fdb0] c000000000012474 kernel_init+0x24/0x160
[c000000c6d19fe20] c00000000000cbd0 ret_from_kernel_thread+0x5c/0x6c
33:mon>

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902040122.136414-1-aneesh.kumar@linux.ibm.com
2020-09-02 22:14:26 +10:00
Christophe Leroy
c20beffeec powerpc/uaccess: Use flexible addressing with __put_user()/__get_user()
At the time being, __put_user()/__get_user() and friends only use
D-form addressing, with 0 offset. Ex:

	lwz	reg1, 0(reg2)

Give the compiler the opportunity to use other adressing modes
whenever possible, to get more optimised code.

Hereunder is a small exemple:

struct test {
	u32 item1;
	u16 item2;
	u8 item3;
	u64 item4;
};

int set_test_user(struct test __user *from, struct test __user *to)
{
	int err;
	u32 item1;
	u16 item2;
	u8 item3;
	u64 item4;

	err = __get_user(item1, &from->item1);
	err |= __get_user(item2, &from->item2);
	err |= __get_user(item3, &from->item3);
	err |= __get_user(item4, &from->item4);

	err |= __put_user(item1, &to->item1);
	err |= __put_user(item2, &to->item2);
	err |= __put_user(item3, &to->item3);
	err |= __put_user(item4, &to->item4);

	return err;
}

Before the patch:

00000df0 <set_test_user>:
 df0:	94 21 ff f0 	stwu    r1,-16(r1)
 df4:	39 40 00 00 	li      r10,0
 df8:	93 c1 00 08 	stw     r30,8(r1)
 dfc:	93 e1 00 0c 	stw     r31,12(r1)
 e00:	7d 49 53 78 	mr      r9,r10
 e04:	80 a3 00 00 	lwz     r5,0(r3)
 e08:	38 e3 00 04 	addi    r7,r3,4
 e0c:	7d 46 53 78 	mr      r6,r10
 e10:	a0 e7 00 00 	lhz     r7,0(r7)
 e14:	7d 29 33 78 	or      r9,r9,r6
 e18:	39 03 00 06 	addi    r8,r3,6
 e1c:	7d 46 53 78 	mr      r6,r10
 e20:	89 08 00 00 	lbz     r8,0(r8)
 e24:	7d 29 33 78 	or      r9,r9,r6
 e28:	38 63 00 08 	addi    r3,r3,8
 e2c:	7d 46 53 78 	mr      r6,r10
 e30:	83 c3 00 00 	lwz     r30,0(r3)
 e34:	83 e3 00 04 	lwz     r31,4(r3)
 e38:	7d 29 33 78 	or      r9,r9,r6
 e3c:	7d 43 53 78 	mr      r3,r10
 e40:	90 a4 00 00 	stw     r5,0(r4)
 e44:	7d 29 1b 78 	or      r9,r9,r3
 e48:	38 c4 00 04 	addi    r6,r4,4
 e4c:	7d 43 53 78 	mr      r3,r10
 e50:	b0 e6 00 00 	sth     r7,0(r6)
 e54:	7d 29 1b 78 	or      r9,r9,r3
 e58:	38 e4 00 06 	addi    r7,r4,6
 e5c:	7d 43 53 78 	mr      r3,r10
 e60:	99 07 00 00 	stb     r8,0(r7)
 e64:	7d 23 1b 78 	or      r3,r9,r3
 e68:	38 84 00 08 	addi    r4,r4,8
 e6c:	93 c4 00 00 	stw     r30,0(r4)
 e70:	93 e4 00 04 	stw     r31,4(r4)
 e74:	7c 63 53 78 	or      r3,r3,r10
 e78:	83 c1 00 08 	lwz     r30,8(r1)
 e7c:	83 e1 00 0c 	lwz     r31,12(r1)
 e80:	38 21 00 10 	addi    r1,r1,16
 e84:	4e 80 00 20 	blr

After the patch:

00000dbc <set_test_user>:
 dbc:	39 40 00 00 	li      r10,0
 dc0:	7d 49 53 78 	mr      r9,r10
 dc4:	80 03 00 00 	lwz     r0,0(r3)
 dc8:	7d 48 53 78 	mr      r8,r10
 dcc:	a1 63 00 04 	lhz     r11,4(r3)
 dd0:	7d 29 43 78 	or      r9,r9,r8
 dd4:	7d 48 53 78 	mr      r8,r10
 dd8:	88 a3 00 06 	lbz     r5,6(r3)
 ddc:	7d 29 43 78 	or      r9,r9,r8
 de0:	7d 48 53 78 	mr      r8,r10
 de4:	80 c3 00 08 	lwz     r6,8(r3)
 de8:	80 e3 00 0c 	lwz     r7,12(r3)
 dec:	7d 29 43 78 	or      r9,r9,r8
 df0:	7d 43 53 78 	mr      r3,r10
 df4:	90 04 00 00 	stw     r0,0(r4)
 df8:	7d 29 1b 78 	or      r9,r9,r3
 dfc:	7d 43 53 78 	mr      r3,r10
 e00:	b1 64 00 04 	sth     r11,4(r4)
 e04:	7d 29 1b 78 	or      r9,r9,r3
 e08:	7d 43 53 78 	mr      r3,r10
 e0c:	98 a4 00 06 	stb     r5,6(r4)
 e10:	7d 23 1b 78 	or      r3,r9,r3
 e14:	90 c4 00 08 	stw     r6,8(r4)
 e18:	90 e4 00 0c 	stw     r7,12(r4)
 e1c:	7c 63 53 78 	or      r3,r3,r10
 e20:	4e 80 00 20 	blr

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c27bc4e598daf3bbb225de7a1f5c52121cf1e279.1597235091.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:23 +10:00
Christophe Leroy
76d46a1e2f powerpc: Remove flush_instruction_cache() on 8xx
flush_instruction_cache() is never used on 8xx, remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/245cabd8f291facac8c8c5fd370e361a69e02860.1597384145.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:22 +10:00
Stephen Rothwell
6b1992bcde powerpc: unrel_branch_check.sh: enable the use of llvm-objdump v9, 10 or 11
Currently, using llvm-objtool, this script just silently succeeds without
actually do the intended checking.  So this updates it to work properly.

Firstly, llvm-objdump does not add target symbol names to the end
of branches in its asm output, so we have to drop the branch to
__start_initialization_multiplatform using its address.

Secondly, v9 and 10 specify branch targets as .+<offset>, so we convert
those to actual addresses.

Thirdly, v10 and 11 error out on a vmlinux if given the -R option
complaining that it is "not a dynamic object".  The -R does not make
any difference to the asm output, so remove it.

Lastly, v11 produces asm that is very similar to Gnu objtool (at least
as far as branches are concerned), so no further changes are necessary
to make it work.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200812081036.7969-3-sfr@canb.auug.org.au
2020-09-02 11:00:22 +10:00
Stephen Rothwell
b71dca9891 powerpc: unrel_branch_check.sh: use nm to find symbol value
This is considerably faster then parsing the objdump asm output.  It will
also make the enabling of llvm-objdump a little easier.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200812081036.7969-2-sfr@canb.auug.org.au
2020-09-02 11:00:22 +10:00
Stephen Rothwell
af13a2244d powerpc: unrel_branch_check.sh: exit silently for early errors
If we can't find the address of __end_interrupts, then we still exit
successfully as that is the current behaviour.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-8-sfr@canb.auug.org.au
2020-09-02 11:00:22 +10:00
Stephen Rothwell
3745ae63b4 powerpc: unrel_branch_check.sh: fix up the file header
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-7-sfr@canb.auug.org.au
2020-09-02 11:00:22 +10:00
Stephen Rothwell
b84eaab6ed powerpc: unrel_branch_check.sh: simplify and tidy up the final loop
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-6-sfr@canb.auug.org.au
2020-09-02 11:00:22 +10:00
Stephen Rothwell
3d97abbc9f powerpc: unrel_branch_check.sh: convert grep | sed | awk to just sed
Also start using sed -E and make all the separate expressions into a
single one with comments.  Pull the stripping of condition registers
back into the sed command.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-5-sfr@canb.auug.org.au
2020-09-02 11:00:22 +10:00
Stephen Rothwell
4e71106c34 powerpc: unrel_branch_check.sh: simplify objdump's asm output
We don't use the raw hex instruction dump, so elide it and adjust the
following expressions.

Also use \s instead of [[:space:]] everywhere.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-4-sfr@canb.auug.org.au
2020-09-02 11:00:22 +10:00
Stephen Rothwell
20ff8ec182 powerpc: unrel_branch_check.sh: simplify and combine some executions
Also some minor style changes.

There should still be no change in behaviour.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-3-sfr@canb.auug.org.au
2020-09-02 11:00:21 +10:00
Stephen Rothwell
d9de6b0da8 powerpc: unrel_branch_check.sh: fix shellcheck complaints
No functional change

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811140435.20957-2-sfr@canb.auug.org.au
2020-09-02 11:00:21 +10:00
Scott Cheloha
e5e179aa3a pseries/drmem: don't cache node id in drmem_lmb struct
At memory hot-remove time we can retrieve an LMB's nid from its
corresponding memory_block.  There is no need to store the nid
in multiple locations.

Note that lmb_to_memblock() uses find_memory_block() to get the
corresponding memory_block.  As find_memory_block() runs in sub-linear
time this approach is negligibly slower than what we do at present.

In exchange for this lookup at hot-remove time we no longer need to
call memory_add_physaddr_to_nid() during drmem_init() for each LMB.
On powerpc, memory_add_physaddr_to_nid() is a linear search, so this
spares us an O(n^2) initialization during boot.

On systems with many LMBs that initialization overhead is palpable and
disruptive.  For example, on a box with 249854 LMBs we're seeing
drmem_init() take upwards of 30 seconds to complete:

[   53.721639] drmem: initializing drmem v2
[   80.604346] watchdog: BUG: soft lockup - CPU#65 stuck for 23s! [swapper/0:1]
[   80.604377] Modules linked in:
[   80.604389] CPU: 65 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc2+ #4
[   80.604397] NIP:  c0000000000a4980 LR: c0000000000a4940 CTR: 0000000000000000
[   80.604407] REGS: c0002dbff8493830 TRAP: 0901   Not tainted  (5.6.0-rc2+)
[   80.604412] MSR:  8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE>  CR: 44000248  XER: 0000000d
[   80.604431] CFAR: c0000000000a4a38 IRQMASK: 0
[   80.604431] GPR00: c0000000000a4940 c0002dbff8493ac0 c000000001904400 c0003cfffffede30
[   80.604431] GPR04: 0000000000000000 c000000000f4095a 000000000000002f 0000000010000000
[   80.604431] GPR08: c0000bf7ecdb7fb8 c0000bf7ecc2d3c8 0000000000000008 c00c0002fdfb2001
[   80.604431] GPR12: 0000000000000000 c00000001e8ec200
[   80.604477] NIP [c0000000000a4980] hot_add_scn_to_nid+0xa0/0x3e0
[   80.604486] LR [c0000000000a4940] hot_add_scn_to_nid+0x60/0x3e0
[   80.604492] Call Trace:
[   80.604498] [c0002dbff8493ac0] [c0000000000a4940] hot_add_scn_to_nid+0x60/0x3e0 (unreliable)
[   80.604509] [c0002dbff8493b20] [c000000000087c10] memory_add_physaddr_to_nid+0x20/0x60
[   80.604521] [c0002dbff8493b40] [c0000000010d4880] drmem_init+0x25c/0x2f0
[   80.604530] [c0002dbff8493c10] [c000000000010154] do_one_initcall+0x64/0x2c0
[   80.604540] [c0002dbff8493ce0] [c0000000010c4aa0] kernel_init_freeable+0x2d8/0x3a0
[   80.604550] [c0002dbff8493db0] [c000000000010824] kernel_init+0x2c/0x148
[   80.604560] [c0002dbff8493e20] [c00000000000b648] ret_from_kernel_thread+0x5c/0x74
[   80.604567] Instruction dump:
[   80.604574] 392918e8 e9490000 e90a000a e92a0000 80ea000c 1d080018 3908ffe8 7d094214
[   80.604586] 7fa94040 419d00dc e9490010 714a0088 <2faa0008> 409e00ac e9490000 7fbe5040
[   89.047390] drmem: 249854 LMB(s)

With a patched kernel on the same machine we're no longer seeing the
soft lockup.  drmem_init() now completes in negligible time, even when
the LMB count is large.

Fixes: b2d3b5ee66 ("powerpc/pseries: Track LMB nid instead of using device tree")
Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200811015115.63677-1-cheloha@linux.ibm.com
2020-09-02 11:00:21 +10:00
Christophe Leroy
704dfe931d powerpc: Rewrite FSL_BOOKE flush_cache_instruction() in C
Nothing prevents flush_cache_instruction() from being writen in C.

Do it to improve readability and maintainability.

This function is only use by low level callers, it is not
intended to be used by module. Don't export it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f989eff8296800c427622c0985384148404e4f0b.1597384512.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:21 +10:00
Christophe Leroy
de39b19452 powerpc: Rewrite 4xx flush_cache_instruction() in C
Nothing prevents flush_cache_instruction() from being writen in C.

Do it to improve readability and maintainability.

This function is very small and isn't called from assembly,
make it static inline in asm/cacheflush.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/93d93fc69b4b3ad3ceba2fc0756333c0c0245bb7.1597384512.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:21 +10:00
Christophe Leroy
f663f33120 powerpc: Move flush_instruction_cache() prototype in asm/cacheflush.h
flush_instruction_cache() belongs to the cache flushing function
family.

Move its prototype in asm/cacheflush.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/993445b5227e8ca2f0e38bcc9ea3dfea6e865920.1597384512.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:21 +10:00
Christophe Leroy
e426ab39f4 powerpc: Remove flush_instruction_cache for book3s/32
The only callers of flush_instruction_cache() are:

arch/powerpc/kernel/swsusp_booke.S:	bl flush_instruction_cache
arch/powerpc/mm/nohash/40x.c:	flush_instruction_cache();
arch/powerpc/mm/nohash/44x.c:	flush_instruction_cache();
arch/powerpc/mm/nohash/fsl_booke.c:	flush_instruction_cache();
arch/powerpc/platforms/44x/machine_check.c:			flush_instruction_cache();
arch/powerpc/platforms/44x/machine_check.c:		flush_instruction_cache();

This function is not used by book3s/32, drop it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/50098f49877cea0f46730a9df82dcabf84160e4b.1597384512.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:21 +10:00
Nathan Lynch
9d6792ffe1 powerpc/pseries: explicitly reschedule during drmem_lmb list traversal
The drmem lmb list can have hundreds of thousands of entries, and
unfortunately lookups take the form of linear searches. As long as
this is the case, traversals have the potential to monopolize the CPU
and provoke lockup reports, workqueue stalls, and the like unless
they explicitly yield.

Rather than placing cond_resched() calls within various
for_each_drmem_lmb() loop blocks in the code, put it in the iteration
expression of the loop macro itself so users can't omit it.

Introduce a drmem_lmb_next() iteration helper function which calls
cond_resched() at a regular interval during array traversal. Each
iteration of the loop in DLPAR code paths can involve around ten RTAS
calls which can each take up to 250us, so this ensures the check is
performed at worst every few milliseconds.

Fixes: 6c6ea53725 ("powerpc/mm: Separate ibm, dynamic-memory data from DT format")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200813151131.2070161-1-nathanl@linux.ibm.com
2020-09-02 11:00:20 +10:00
Christophe Leroy
e53281bc21 powerpc: Drop _nmask_and_or_msr()
_nmask_and_or_msr() is only used at two places to set MSR_IP.

The SYNC is unnecessary as the users are not PowerPC 601.

Can be easily writen in C.

Do it, and drop _nmask_and_or_msr()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c2d2b8dfb8dd677026b26dffc8d31070c38a6b89.1597388079.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:20 +10:00
Stephen Kitt
6c9100ea39 powerpc: Use simple i2c probe function
The i2c probe functions here don't use the id information provided in
their second argument, so the single-parameter i2c probe
function ("probe_new") can be used instead.

This avoids scanning the identifier tables during probes.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Acked-by: Wolfram Sang <wsa@kernel.org>
Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200807152713.381588-1-steve@sk2.org
2020-09-02 11:00:20 +10:00
Scott Cheloha
5d1bc77642 powerpc/pseries: new lparcfg key/value pair: partition_affinity_score
The H_GetPerformanceCounterInfo (GPCI) PHYP hypercall has a subcall,
Affinity_Domain_Info_By_Partition, which returns, among other things,
a "partition affinity score" for a given LPAR.  This score, a value on
[0-100], represents the processor-memory affinity for the LPAR in
question.  A score of 0 indicates the worst possible affinity while a
score of 100 indicates perfect affinity.  The score can be used to
reason about performance.

This patch adds the score for the local LPAR to the lparcfg procfile
under a new 'partition_affinity_score' key.

Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Acked-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200727184605.2945095-2-cheloha@linux.ibm.com
2020-09-02 11:00:20 +10:00
Scott Cheloha
59562b5c33 powerpc/perf: consolidate GPCI hcall structs into asm/hvcall.h
The H_GetPerformanceCounterInfo (GPCI) hypercall input/output structs are
useful to modules outside of perf/, so move them into asm/hvcall.h to live
alongside the other powerpc hypercall structs.

Leave the perf-specific GPCI stuff in perf/hv-gpci.h.

Signed-off-by: Scott Cheloha <cheloha@linux.ibm.com>
Acked-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200727184605.2945095-1-cheloha@linux.ibm.com
2020-09-02 11:00:20 +10:00
Christophe Leroy
82eb179242 powerpc: drop hard_reset_now() and poweroff_now() declaration
Those function have never existed. Drop their declaration.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/edcdd72a36495d25213c0256c8022367458e0d19.1596716418.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:20 +10:00
Christophe Leroy
63442de430 powerpc/fpu: Drop cvt_fd() and cvt_df()
Those two functions have been unused since commit identified below.
Drop them.

Fixes: 31bfdb036f ("powerpc: Use instruction emulation infrastructure to handle alignment faults")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d5641ada199b8dd2af16ad00a66084cf974f2704.1596716418.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:19 +10:00
Christophe Leroy
b134cfc3e3 powerpc/irq: Drop forward declaration of struct irqaction
Since the commit identified below, the forward declaration of
struct irqaction is useless. Drop it.

Fixes: b709c08328 ("ppc64: move stack switching up in interrupt processing")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e0bcdabac45fcd26c02d7df273bd4a5827c6033d.1596716375.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:19 +10:00
Christophe Leroy
169b9afee5 powerpc/hwirq: Remove stale forward irq_chip declaration
Since commit identified below, the forward declaration of
struct irq_chip is useless (was struct hw_interrupt_type at that time)

Remove it, together with the associated comment.

Fixes: c0ad90a32f ("[PATCH] genirq: add ->retrigger() irq op to consolidate hw_irq_resend()")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fbe58d27cf128d5fe581e4510ded8701858f268e.1596716328.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:18 +10:00
Christophe Leroy
b51ba4fe2e powerpc/32s: Fix assembler warning about r0
The assembler says:
  arch/powerpc/kernel/head_32.S:1095: Warning: invalid register expression

It's objecting to the use of r0 as the RA argument. That's because
when RA = 0 the literal value 0 is used, rather than the content of
r0, making the use of r0 in the source potentially confusing.

Fix it to use a literal 0, the generated code is identical.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2b69ac8e1cddff6f808fc7415907179eab4aae9e.1596693679.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:17 +10:00
Kees Cook
c604abc3f6 vmlinux.lds.h: Split ELF_DETAILS from STABS_DEBUG
The .comment section doesn't belong in STABS_DEBUG. Split it out into a
new macro named ELF_DETAILS. This will gain other non-debug sections
that need to be accounted for when linking with --orphan-handling=warn.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: linux-arch@vger.kernel.org
Link: https://lore.kernel.org/r/20200821194310.3089815-5-keescook@chromium.org
2020-09-01 09:50:35 +02:00
Linus Torvalds
b69bea8a65 A set of fixes for lockdep, tracing and RCU:
- Prevent recursion by using raw_cpu_* operations
 
   - Fixup the interrupt state in the cpu idle code to be consistent
 
   - Push rcu_idle_enter/exit() invocations deeper into the idle path so
     that the lock operations are inside the RCU watching sections
 
   - Move trace_cpu_idle() into generic code so it's called before RCU goes
     idle.
 
   - Handle raw_local_irq* vs. local_irq* operations correctly
 
   - Move the tracepoints out from under the lockdep recursion handling
     which turned out to be fragile and inconsistent.
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Merge tag 'locking-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fixes from Thomas Gleixner:
 "A set of fixes for lockdep, tracing and RCU:

   - Prevent recursion by using raw_cpu_* operations

   - Fixup the interrupt state in the cpu idle code to be consistent

   - Push rcu_idle_enter/exit() invocations deeper into the idle path so
     that the lock operations are inside the RCU watching sections

   - Move trace_cpu_idle() into generic code so it's called before RCU
     goes idle.

   - Handle raw_local_irq* vs. local_irq* operations correctly

   - Move the tracepoints out from under the lockdep recursion handling
     which turned out to be fragile and inconsistent"

* tag 'locking-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep,trace: Expose tracepoints
  lockdep: Only trace IRQ edges
  mips: Implement arch_irqs_disabled()
  arm64: Implement arch_irqs_disabled()
  nds32: Implement arch_irqs_disabled()
  locking/lockdep: Cleanup
  x86/entry: Remove unused THUNKs
  cpuidle: Move trace_cpu_idle() into generic code
  cpuidle: Make CPUIDLE_FLAG_TLB_FLUSHED generic
  sched,idle,rcu: Push rcu_idle deeper into the idle path
  cpuidle: Fixup IRQ state
  lockdep: Use raw_cpu_*() for per-cpu variables
2020-08-30 11:43:50 -07:00
Linus Torvalds
8bb5021cc2 powerpc fixes for 5.9 #4
Revert our removal of PROT_SAO, at least one user expressed an interest in using
 it on Power9. Instead don't allow it to be used in guests unless enabled
 explicitly at compile time.
 
 A fix for a crash introduced by a recent change to FP handling.
 
 Revert a change to our idle code that left Power10 with no idle support.
 
 One minor fix for the new scv system call path to set PPR.
 
 Fix a crash in our "generic" PMU if branch stack events were enabled.
 
 A fix for the IMC PMU, to correctly identify host kernel samples.
 
 The ADB_PMU powermac code was found to be incompatible with VMAP_STACK, so make
 them incompatible in Kconfig until the code can be fixed.
 
 A build fix in drivers/video/fbdev/controlfb.c, and a documentation fix.
 
 Thanks to:
   Alexey Kardashevskiy, Athira Rajeev, Christophe Leroy, Giuseppe Sacco,
   Madhavan Srinivasan, Milton Miller, Nicholas Piggin, Pratik Rajesh Sampat,
   Randy Dunlap, Shawn Anastasio, Vaidyanathan Srinivasan.
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Merge tag 'powerpc-5.9-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:

 - Revert our removal of PROT_SAO, at least one user expressed an
   interest in using it on Power9. Instead don't allow it to be used in
   guests unless enabled explicitly at compile time.

 - A fix for a crash introduced by a recent change to FP handling.

 - Revert a change to our idle code that left Power10 with no idle
   support.

 - One minor fix for the new scv system call path to set PPR.

 - Fix a crash in our "generic" PMU if branch stack events were enabled.

 - A fix for the IMC PMU, to correctly identify host kernel samples.

 - The ADB_PMU powermac code was found to be incompatible with
   VMAP_STACK, so make them incompatible in Kconfig until the code can
   be fixed.

 - A build fix in drivers/video/fbdev/controlfb.c, and a documentation
   fix.

Thanks to Alexey Kardashevskiy, Athira Rajeev, Christophe Leroy,
Giuseppe Sacco, Madhavan Srinivasan, Milton Miller, Nicholas Piggin,
Pratik Rajesh Sampat, Randy Dunlap, Shawn Anastasio, Vaidyanathan
Srinivasan.

* tag 'powerpc-5.9-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/32s: Disable VMAP stack which CONFIG_ADB_PMU
  Revert "powerpc/powernv/idle: Replace CPU feature check with PVR check"
  powerpc/perf: Fix reading of MSR[HV/PR] bits in trace-imc
  powerpc/perf: Fix crashes with generic_compat_pmu & BHRB
  powerpc/64s: Fix crash in load_fp_state() due to fpexc_mode
  powerpc/64s: scv entry should set PPR
  Documentation/powerpc: fix malformed table in syscall64-abi
  video: fbdev: controlfb: Fix build for COMPILE_TEST=y && PPC_PMAC=n
  selftests/powerpc: Update PROT_SAO test to skip ISA 3.1
  powerpc/64s: Disallow PROT_SAO in LPARs by default
  Revert "powerpc/64s: Remove PROT_SAO support"
2020-08-30 10:56:12 -07:00
Aneesh Kumar K.V
103a8542cb powerpc/book3s64/radix: Fix boot failure with large amount of guest memory
If the hypervisor doesn't support hugepages, the kernel ends up allocating a large
number of page table pages. The early page table allocation was wrongly
setting the max memblock limit to ppc64_rma_size with radix translation
which resulted in boot failure as shown below.

Kernel panic - not syncing:
early_alloc_pgtable: Failed to allocate 16777216 bytes align=0x1000000 nid=-1 from=0x0000000000000000 max_addr=0xffffffffffffffff
 CPU: 0 PID: 0 Comm: swapper Not tainted 5.8.0-24.9-default+ #2
 Call Trace:
 [c0000000016f3d00] [c0000000007c6470] dump_stack+0xc4/0x114 (unreliable)
 [c0000000016f3d40] [c00000000014c78c] panic+0x164/0x418
 [c0000000016f3dd0] [c000000000098890] early_alloc_pgtable+0xe0/0xec
 [c0000000016f3e60] [c0000000010a5440] radix__early_init_mmu+0x360/0x4b4
 [c0000000016f3ef0] [c000000001099bac] early_init_mmu+0x1c/0x3c
 [c0000000016f3f10] [c00000000109a320] early_setup+0x134/0x170

This was because the kernel was checking for the radix feature before we enable the
feature via mmu_features. This resulted in the kernel using hash restrictions on
radix.

Rework the early init code such that the kernel boot with memblock restrictions
as imposed by hash. At that point, the kernel still hasn't finalized the
translation the kernel will end up using.

We have three different ways of detecting radix.

1. dt_cpu_ftrs_scan -> used only in case of PowerNV
2. ibm,pa-features -> Used when we don't use cpu_dt_ftr_scan
3. CAS -> Where we negotiate with hypervisor about the supported translation.

We look at 1 or 2 early in the boot and after that, we look at the CAS vector to
finalize the translation the kernel will use. We also support a kernel command
line option (disable_radix) to switch to hash.

Update the memblock limit after mmu_early_init_devtree() if the kernel is going
to use radix translation. This forces some of the memblock allocations we do before
mmu_early_init_devtree() to be within the RMA limit.

Fixes: 2bfd65e45e ("powerpc/mm/radix: Add radix callbacks for early init routines")
Reported-by: Shirisha Ganta <shiganta@in.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200828100852.426575-1-aneesh.kumar@linux.ibm.com
2020-08-28 20:14:45 +10:00
Christophe Leroy
4a133eb351 powerpc/32s: Disable VMAP stack which CONFIG_ADB_PMU
low_sleep_handler() can't restore the context from virtual
stack because the stack can hardly be accessed with MMU OFF.

For now, disable VMAP stack when CONFIG_ADB_PMU is selected.

Fixes: cd08f109e2 ("powerpc/32s: Enable CONFIG_VMAP_STACK")
Cc: stable@vger.kernel.org # v5.6+
Reported-by: Giuseppe Sacco <giuseppe@sguazz.it>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ec96c15bfa1a7415ab604ee1c98cd45779c08be0.1598553015.git.christophe.leroy@csgroup.eu
2020-08-28 12:03:18 +10:00
Pratik Rajesh Sampat
16d83a540c Revert "powerpc/powernv/idle: Replace CPU feature check with PVR check"
cpuidle stop state implementation has minor optimizations for P10
where hardware preserves more SPR registers compared to P9. The
current P9 driver works for P10, although does few extra
save-restores. P9 driver can provide the required power management
features like SMT thread folding and core level power savings on a P10
platform.

Until the P10 stop driver is available, revert the commit which allows
for only P9 systems to utilize cpuidle and blocks all idle stop states
for P10. CPU idle states are enabled and tested on the P10 platform
with this fix.

This reverts commit 8747bf36f3.

Fixes: 8747bf36f3 ("powerpc/powernv/idle: Replace CPU feature check with PVR check")
Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com>
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200826082918.89306-1-psampat@linux.ibm.com
2020-08-27 17:41:45 +10:00
Athira Rajeev
82715a0f33 powerpc/perf: Fix reading of MSR[HV/PR] bits in trace-imc
IMC trace-mode uses MSR[HV/PR] bits to set the cpumode for the
instruction pointer captured in each sample. The bits are fetched from
the third double word of the trace record. Reading third double word
from IMC trace record should use be64_to_cpu() along with READ_ONCE
inorder to fetch correct MSR[HV/PR] bits. Patch addresses this change.

Currently we are using PERF_RECORD_MISC_HYPERVISOR as cpumode if MSR
HV is 1 and PR is 0 which means the address is from host counter. But
using PERF_RECORD_MISC_HYPERVISOR for host counter data will fail to
resolve the address -> symbol during "perf report" because perf tools
side uses PERF_RECORD_MISC_KERNEL to represent the host counter data.
Therefore, fix the trace imc sample data to use
PERF_RECORD_MISC_KERNEL as cpumode for host kernel information.

Fixes: 77ca3951cc ("powerpc/perf: Add kernel support for new MSR[HV PR] bits in trace-imc")
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1598424029-1662-1-git-send-email-atrajeev@linux.vnet.ibm.com
2020-08-27 17:41:45 +10:00
Alexey Kardashevskiy
b460b51241 powerpc/perf: Fix crashes with generic_compat_pmu & BHRB
The bhrb_filter_map ("The Branch History Rolling Buffer") callback is
only defined in raw CPUs' power_pmu structs. The "architected" CPUs
use generic_compat_pmu, which does not have this callback, and crashes
occur if a user tries to enable branch stack for an event.

This add a NULL pointer check for bhrb_filter_map() which behaves as
if the callback returned an error.

This does not add the same check for config_bhrb() as the only caller
checks for cpuhw->bhrb_users which remains zero if bhrb_filter_map==0.

Fixes: be80e758d0 ("powerpc/perf: Add generic compat mode pmu driver")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200602025612.62707-1-aik@ozlabs.ru
2020-08-27 17:41:44 +10:00
Michael Ellerman
b91eb51824 powerpc/64s: Fix crash in load_fp_state() due to fpexc_mode
The recent commit 01eb01877f ("powerpc/64s: Fix restore_math
unnecessarily changing MSR") changed some of the handling of floating
point/vector restore.

In particular it caused current->thread.fpexc_mode to be copied into
the current MSR (via msr_check_and_set()), rather than just into
regs->msr (which is moved into MSR on return to userspace).

This can lead to a crash in the kernel if we take a floating point
exception when restoring FPSCR:

  Oops: Exception in kernel mode, sig: 8 [#1]
  LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV
  Modules linked in:
  CPU: 3 PID: 101213 Comm: ld64.so.2 Not tainted 5.9.0-rc1-00098-g18445bf405cb-dirty #9
  NIP:  c00000000000fbb4 LR: c00000000001a7ac CTR: c000000000183570
  REGS: c0000016b7cfb3b0 TRAP: 0700   Not tainted  (5.9.0-rc1-00098-g18445bf405cb-dirty)
  MSR:  900000000290b933 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>  CR: 44002444  XER: 00000000
  CFAR: c00000000001a7a8 IRQMASK: 1
  GPR00: c00000000001ae40 c0000016b7cfb640 c0000000011b7f00 c000001542a0f740
  GPR04: c000001542a0f720 c000001542a0eb00 0000000000000900 c000001542a0eb00
  GPR08: 000000000000000a 0000000000002000 9000000000009033 0000000000000000
  GPR12: 0000000000004000 c0000017ffffd900 0000000000000001 c000000000df5a58
  GPR16: c000000000e19c18 c0000000010e1123 0000000000000001 c000000000e1a638
  GPR20: 0000000000000000 c0000000044b1d00 0000000000000000 c000001542a0f2a0
  GPR24: 00000016c7fe0000 c000001542a0f720 c000000001c93da0 c000000000fe5f28
  GPR28: c000001542a0f720 0000000000800000 c0000016b7cfbe90 0000000002802900
  NIP load_fp_state+0x4/0x214
  LR  restore_math+0x17c/0x1f0
  Call Trace:
    0xc0000016b7cfb680 (unreliable)
    __switch_to+0x330/0x460
    __schedule+0x318/0x920
    schedule+0x74/0x140
    schedule_timeout+0x318/0x3f0
    wait_for_completion+0xc8/0x210
    call_usermodehelper_exec+0x234/0x280
    do_coredump+0xedc/0x13c0
    get_signal+0x1d4/0xbe0
    do_notify_resume+0x1a0/0x490
    interrupt_exit_user_prepare+0x1c4/0x230
    interrupt_return+0x14/0x1c0
  Instruction dump:
  ebe10168 e88101a0 7c8ff120 382101e0 e8010010 7c0803a6 4e800020 790605c4
  782905c4 7c0008a8 7c0008a8 c8030200 <fffe058e> 48000088 c8030000 c8230010

Fix it by only loading the fpexc_mode value into regs->msr.

Also add a comment to explain that although VSX is subject to the
value of fpexc_mode, we don't have to handle that separately because
we only allow VSX to be enabled if FP is also enabled.

Fixes: 01eb01877f ("powerpc/64s: Fix restore_math unnecessarily changing MSR")
Reported-by: Milton Miller <miltonm@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Link: https://lore.kernel.org/r/20200825093424.3967813-1-mpe@ellerman.id.au
2020-08-27 17:41:39 +10:00
Nicholas Piggin
e5fe56092e powerpc/64s: scv entry should set PPR
Kernel entry sets PPR to HMT_MEDIUM by convention. The scv entry
path missed this.

Fixes: 7fa95f9ada ("powerpc/64s: system call support for scv/rfscv instructions")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200825075309.224184-1-npiggin@gmail.com
2020-08-27 17:41:13 +10:00
Nicholas Piggin
044d0d6de9 lockdep: Only trace IRQ edges
Problem:

  raw_local_irq_save(); // software state on
  local_irq_save(); // software state off
  ...
  local_irq_restore(); // software state still off, because we don't enable IRQs
  raw_local_irq_restore(); // software state still off, *whoopsie*

existing instances:

 - lock_acquire()
     raw_local_irq_save()
     __lock_acquire()
       arch_spin_lock(&graph_lock)
         pv_wait() := kvm_wait() (same or worse for Xen/HyperV)
           local_irq_save()

 - trace_clock_global()
     raw_local_irq_save()
     arch_spin_lock()
       pv_wait() := kvm_wait()
	 local_irq_save()

 - apic_retrigger_irq()
     raw_local_irq_save()
     apic->send_IPI() := default_send_IPI_single_phys()
       local_irq_save()

Possible solutions:

 A) make it work by enabling the tracing inside raw_*()
 B) make it work by keeping tracing disabled inside raw_*()
 C) call it broken and clean it up now

Now, given that the only reason to use the raw_* variant is because you don't
want tracing. Therefore A) seems like a weird option (although it can be done).
C) is tempting, but OTOH it ends up converting a _lot_ of code to raw just
because there is one raw user, this strips the validation/tracing off for all
the other users.

So we pick B) and declare any code that ends up doing:

	raw_local_irq_save()
	local_irq_save()
	lockdep_assert_irqs_disabled();

broken. AFAICT this problem has existed forever, the only reason it came
up is because commit: 859d069ee1 ("lockdep: Prepare for NMI IRQ
state tracking") changed IRQ tracing vs lockdep recursion and the
first instance is fairly common, the other cases hardly ever happen.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[rewrote changelog]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20200723105615.1268126-1-npiggin@gmail.com
2020-08-26 12:41:56 +02:00
Oliver O'Halloran
3ced132a05 powerpc/nx: Don't pack struct coprocessor_request_block
Building with W=1 results in the following warning:

In file included from arch/powerpc/platforms/powernv/vas-fault.c:16:
./arch/powerpc/include/asm/icswx.h:159:1: error: alignment 1 of ‘struct
	coprocessor_request_block’ is less than 16 [-Werror=packed-not-aligned]
  159 | } __packed;
      | ^
./arch/powerpc/include/asm/icswx.h:159:1: error: alignment 1 of ‘struct
	coprocessor_request_block’ is less than 16 [-Werror=packed-not-aligned]
./arch/powerpc/include/asm/icswx.h:159:1: error: alignment 1 of ‘struct
	coprocessor_request_block’ is less than 16 [-Werror=packed-not-aligned]
./arch/powerpc/include/asm/icswx.h:159:1: error: alignment 1 of ‘struct
	coprocessor_request_block’ is less than 16 [-Werror=packed-not-aligned]
cc1: all warnings being treated as errors

This happens because coprocessor_request_block includes several
sub-structures with an alignment specified using the __aligned(XX)
attribute. The problem comes from coprocessor_request_block having the
__packed attribute. Packing the structure causes the preferred alignment of
the nested structures to be ignored and we get the warnings as a result.

This isn't a problem in practice since the struct is defined with explicit
padding in the form of reserved fields, but we'd like to get rid of the
spurious warnings. The simplest solution is to remove the packed attribute
and use a BUILD_BUG_ON() to ensure the struct is the correct (expected by
HW) size compile time.

Also add a __aligned(128) to the request block structure since Book4 for P8
suggests the HW requires it to be aligned to a 128 byte boundary. There's a
similar requirement for P9 since the COPY and PASTE instructions used to
invoke VAS/NX accelerators operates on a cache line boundary.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-7-oohall@gmail.com
2020-08-25 01:31:33 +10:00
Oliver O'Halloran
fb248c3121 powerpc/powernv: Fix spurious kerneldoc warnings in opal-prd.c
Comments opening with /** are parsed by kerneldoc and this causes the
following warning to be printed:

	arch/powerpc/platforms/powernv/opal-prd.c:31: warning: cannot understand
	function prototype: 'struct opal_prd_msg_queue_item '

opal_prd_mesg_queue_item is an internal data structure so there's no real
need for it to be documented at all. Fix up the comment to squash the
warning.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-5-oohall@gmail.com
2020-08-25 01:31:33 +10:00
Oliver O'Halloran
3b70464aa7 powerpc/powernv: Staticify functions without prototypes
There's a few scattered in the powernv platform.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-4-oohall@gmail.com
2020-08-25 01:31:33 +10:00
Oliver O'Halloran
8471c1dd93 powerpc/powernv: Include asm/powernv.h from the local powernv.h
The asm/powernv.h header provides prototypes for functions which need to be
called by non-powernv platform code. Also include it in the powernv.h
that's local to the platform directory to squash some warnings about
non-static functions missing prototypes.

Also include powernv.h since from opal-memcons.c since it has the
prototypes for the memcons wrangling functions which are used for the opal
and ultravisor msglog.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-3-oohall@gmail.com
2020-08-25 01:31:33 +10:00
Oliver O'Halloran
f6bac19cf6 powerpc/powernv/smp: Fix spurious DBG() warning
When building with W=1 we get the following warning:

 arch/powerpc/platforms/powernv/smp.c: In function ‘pnv_smp_cpu_kill_self’:
 arch/powerpc/platforms/powernv/smp.c:276:16: error: suggest braces around
 	empty body in an ‘if’ statement [-Werror=empty-body]
   276 |      cpu, srr1);
       |                ^
 cc1: all warnings being treated as errors

The full context is this block:

 if (srr1 && !generic_check_cpu_restart(cpu))
 	DBG("CPU%d Unexpected exit while offline srr1=%lx!\n",
 			cpu, srr1);

When building with DEBUG undefined DBG() expands to nothing and GCC emits
the warning due to the lack of braces around an empty statement.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804005410.146094-2-oohall@gmail.com
2020-08-25 01:31:33 +10:00
Colin Ian King
346427e668 powerpc/oprofile: fix spelling mistake "contex" -> "context"
There is a spelling mistake in a pr_debug message. Fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200804174316.402425-1-colin.king@canonical.com
2020-08-25 01:31:33 +10:00
Aneesh Kumar K.V
1c0a7ac0ec powerpc/vmemmap: Don't warn if we don't find a mapping vmemmap list entry
Now that we are handling vmemmap list allocation failure correctly, don't
WARN in section deactivate when we don't find a mapping vmemmap list entry.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200731113500.248306-2-aneesh.kumar@linux.ibm.com
2020-08-25 01:31:33 +10:00
Aneesh Kumar K.V
ccaea15296 powerpc/vmemmap: Fix memory leak with vmemmap list allocation failures.
If we fail to allocate vmemmap list, we don't keep track of allocated
vmemmap block buf. Hence on section deactivate we skip vmemmap block
buf free. This results in memory leak.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200731113500.248306-1-aneesh.kumar@linux.ibm.com
2020-08-25 01:31:32 +10:00
zhengbin
18102e4bcc powerpc/powernv: Remove set but not used variable 'parent'
Fix gcc '-Wunused-but-set-variable' warning:

arch/powerpc/platforms/powernv/pci-ioda.c: In function pnv_ioda_configure_pe:
arch/powerpc/platforms/powernv/pci-ioda.c:867:18: warning: variable parent set but not used [-Wunused-but-set-variable]

It is not used since commit b131a8425c ("powerpc/powernv:
Set PELTV for compound PEs")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1574144074-142032-6-git-send-email-zhengbin13@huawei.com
2020-08-25 01:31:32 +10:00
zhengbin
ef23cf9a89 powerpc/perf: Remove set but not used variable 'target'
Fix gcc '-Wunused-but-set-variable' warning:

arch/powerpc/perf/imc-pmu.c: In function trace_imc_event_init:
arch/powerpc/perf/imc-pmu.c:1292:22: warning: variable target set but not used [-Wunused-but-set-variable]

It is introduced by commit 012ae24484 ("powerpc/perf:
Trace imc PMU functions"), but never used, so remove it.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1574144074-142032-3-git-send-email-zhengbin13@huawei.com
2020-08-25 01:31:32 +10:00
zhengbin
738e6cad0a powerpc/fadump: Remove set but not used variable 'elf'
Fix gcc '-Wunused-but-set-variable' warning:

arch/powerpc/kernel/fadump.c: In function fadump_update_elfcore_header:
arch/powerpc/kernel/fadump.c:790:17: warning: variable elf set but not used [-Wunused-but-set-variable]

It is introduced by commit ebaeb5ae24 ("fadump:
Convert firmware-assisted cpu state dump data into elf notes."),
but never used, so remove it.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1574144074-142032-2-git-send-email-zhengbin13@huawei.com
2020-08-25 01:31:32 +10:00
Biwen Li
843dc8ee23 powerc/dtc/t1024rdb: remove interrupts property
Since the interrupt pin for RTC DS1339 is not connected
to the CPU on T1024RDB, remove the interrupt property
from the device tree.

This also fix the following warning for hwclock.util-linux:
$ hwclock.util-linux
hwclock.util-linux: select() to /dev/rtc0
to wait for clock tick timed out

Signed-off-by: Biwen Li <biwen.li@nxp.com>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200527034228.23793-2-biwen.li@oss.nxp.com
2020-08-25 01:31:32 +10:00
Biwen Li
8c7614d648 powerpc/dts/t4240rdb: remove interrupts property
Since the interrupt pin for RTC DS1374 is not connected
to the CPU on T4240RDB, remove the interrupt property
from the device tree.

This also fix the following warning for hwclock.util-linux:
$ hwclock.util-linux
hwclock.util-linux: select() to /dev/rtc0
to wait for clock tick timed out

Signed-off-by: Biwen Li <biwen.li@nxp.com>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200527034228.23793-1-biwen.li@oss.nxp.com
2020-08-25 01:31:32 +10:00
Frederic Barrat
374f6178f3 ocxl: Remove custom service to allocate interrupts
We now allocate interrupts through xive directly.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200403153838.29224-5-fbarrat@linux.ibm.com
2020-08-25 01:31:31 +10:00
Nicholas Mc Guire
d3e669f31e powerpc/icp-hv: Fix missing of_node_put() in success path
Both of_find_compatible_node() and of_find_node_by_type() will return
a refcounted node on success - thus for the success path the node must
be explicitly released with a of_node_put().

Fixes: 0b05ac6e24 ("powerpc/xics: Rewrite XICS driver")
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1530691407-3991-1-git-send-email-hofrat@osadl.org
2020-08-25 01:31:31 +10:00
Nicholas Mc Guire
67c3e59443 powerpc/pseries: Fix missing of_node_put() in rng_init()
The call to of_find_compatible_node() returns a node pointer with
refcount incremented thus it must be explicitly decremented here
before returning.

Fixes: a489043f46 ("powerpc/pseries: Implement arch_get_random_long() based on H_RANDOM")
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1530522496-14816-1-git-send-email-hofrat@osadl.org
2020-08-25 01:31:31 +10:00
Shawn Anastasio
9b725a90a8 powerpc/64s: Disallow PROT_SAO in LPARs by default
Since migration of guests using SAO to ISA 3.1 hosts may cause issues,
disable PROT_SAO in LPARs by default and introduce a new Kconfig option
PPC_PROT_SAO_LPAR to allow users to enable it if desired.

Signed-off-by: Shawn Anastasio <shawn@anastas.io>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200821185558.35561-3-shawn@anastas.io
2020-08-24 14:12:54 +10:00
Shawn Anastasio
12564485ed Revert "powerpc/64s: Remove PROT_SAO support"
This reverts commit 5c9fa16e8a.

Since PROT_SAO can still be useful for certain classes of software,
reintroduce it. Concerns about guest migration for LPARs using SAO
will be addressed next.

Signed-off-by: Shawn Anastasio <shawn@anastas.io>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200821185558.35561-2-shawn@anastas.io
2020-08-24 14:12:53 +10:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Linus Torvalds
cb95712138 powerpc fixes for 5.9 #3
Add perf support for emitting extended registers for power10.
 
 A fix for CPU hotplug on pseries, where on large/loaded systems we may not wait
 long enough for the CPU to be offlined, leading to crashes.
 
 Addition of a raw cputable entry for Power10, which is not required to boot, but
 is required to make our PMU setup work correctly in guests.
 
 Three fixes for the recent changes on 32-bit Book3S to move modules into their
 own segment for strict RWX.
 
 A fix for a recent change in our powernv PCI code that could lead to crashes.
 
 A change to our perf interrupt accounting to avoid soft lockups when using some
 events, found by syzkaller.
 
 A change in the way we handle power loss events from the hypervisor on pseries.
 We no longer immediately shut down if we're told we're running on a UPS.
 
 A few other minor fixes.
 
 Thanks to:
   Alexey Kardashevskiy, Andreas Schwab, Aneesh Kumar K.V, Anju T Sudhakar,
   Athira Rajeev, Christophe Leroy, Frederic Barrat, Greg Kurz, Kajol Jain,
   Madhavan Srinivasan, Michael Neuling, Michael Roth, Nageswara R Sastry, Oliver
   O'Halloran, Thiago Jung Bauermann, Vaidyanathan Srinivasan, Vasant Hegde.
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Merge tag 'powerpc-5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:

 - Add perf support for emitting extended registers for power10.

 - A fix for CPU hotplug on pseries, where on large/loaded systems we
   may not wait long enough for the CPU to be offlined, leading to
   crashes.

 - Addition of a raw cputable entry for Power10, which is not required
   to boot, but is required to make our PMU setup work correctly in
   guests.

 - Three fixes for the recent changes on 32-bit Book3S to move modules
   into their own segment for strict RWX.

 - A fix for a recent change in our powernv PCI code that could lead to
   crashes.

 - A change to our perf interrupt accounting to avoid soft lockups when
   using some events, found by syzkaller.

 - A change in the way we handle power loss events from the hypervisor
   on pseries. We no longer immediately shut down if we're told we're
   running on a UPS.

 - A few other minor fixes.

Thanks to Alexey Kardashevskiy, Andreas Schwab, Aneesh Kumar K.V, Anju T
Sudhakar, Athira Rajeev, Christophe Leroy, Frederic Barrat, Greg Kurz,
Kajol Jain, Madhavan Srinivasan, Michael Neuling, Michael Roth,
Nageswara R Sastry, Oliver O'Halloran, Thiago Jung Bauermann,
Vaidyanathan Srinivasan, Vasant Hegde.

* tag 'powerpc-5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/perf/hv-24x7: Move cpumask file to top folder of hv-24x7 driver
  powerpc/32s: Fix module loading failure when VMALLOC_END is over 0xf0000000
  powerpc/pseries: Do not initiate shutdown when system is running on UPS
  powerpc/perf: Fix soft lockups due to missed interrupt accounting
  powerpc/powernv/pci: Fix possible crash when releasing DMA resources
  powerpc/pseries/hotplug-cpu: wait indefinitely for vCPU death
  powerpc/32s: Fix is_module_segment() when MODULES_VADDR is defined
  powerpc/kasan: Fix KASAN_SHADOW_START on BOOK3S_32
  powerpc/fixmap: Fix the size of the early debug area
  powerpc/pkeys: Fix build error with PPC_MEM_KEYS disabled
  powerpc/kernel: Cleanup machine check function declarations
  powerpc: Add POWER10 raw mode cputable entry
  powerpc/perf: Add extended regs support for power10 platform
  powerpc/perf: Add support for outputting extended regs in perf intr_regs
  powerpc: Fix P10 PVR revision in /proc/cpuinfo for SMT4 cores
2020-08-23 11:37:23 -07:00
Linus Torvalds
b2d9e99622 * PAE and PKU bugfixes for x86
* selftests fix for new binutils
 * MMU notifier fix for arm64
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:

 - PAE and PKU bugfixes for x86

 - selftests fix for new binutils

 - MMU notifier fix for arm64

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: arm64: Only reschedule if MMU_NOTIFIER_RANGE_BLOCKABLE is not set
  KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()
  kvm: x86: Toggling CR4.PKE does not load PDPTEs in PAE mode
  kvm: x86: Toggling CR4.SMAP does not load PDPTEs in PAE mode
  KVM: x86: fix access code passed to gva_to_gpa
  selftests: kvm: Use a shorter encoding to clear RAX
2020-08-22 10:03:05 -07:00
Will Deacon
fdfe7cbd58 KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()
The 'flags' field of 'struct mmu_notifier_range' is used to indicate
whether invalidate_range_{start,end}() are permitted to block. In the
case of kvm_mmu_notifier_invalidate_range_start(), this field is not
forwarded on to the architecture-specific implementation of
kvm_unmap_hva_range() and therefore the backend cannot sensibly decide
whether or not to block.

Add an extra 'flags' parameter to kvm_unmap_hva_range() so that
architectures are aware as to whether or not they are permitted to block.

Cc: <stable@vger.kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Message-Id: <20200811102725.7121-2-will@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-08-21 18:03:47 -04:00
Kajol Jain
64ef8f2c47 powerpc/perf/hv-24x7: Move cpumask file to top folder of hv-24x7 driver
Commit 792f73f747 ("powerpc/hv-24x7: Add sysfs files inside hv-24x7
device to show cpumask") added cpumask file as part of hv-24x7 driver
inside the interface folder. The cpumask file is supposed to be in the
top folder of the PMU driver in order to make hotplug work.

This patch fixes that issue and creates new group 'cpumask_attr_group'
to add cpumask file and make sure it added in top folder.

  command:# cat /sys/devices/hv_24x7/cpumask
  0

Fixes: 792f73f747 ("powerpc/hv-24x7: Add sysfs files inside hv-24x7 device to show cpumask")
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200821080610.123997-1-kjain@linux.ibm.com
2020-08-21 23:35:27 +10:00
Christophe Leroy
541cebb51f powerpc/32s: Fix module loading failure when VMALLOC_END is over 0xf0000000
In is_module_segment(), when VMALLOC_END is over 0xf0000000,
ALIGN(VMALLOC_END, SZ_256M) has value 0.

In that case, addr >= ALIGN(VMALLOC_END, SZ_256M) is always
true then is_module_segment() always returns false.

Use (ALIGN(VMALLOC_END, SZ_256M) - 1) which will have
value 0xffffffff and will be suitable for the comparison.

Fixes: c496433197 ("powerpc/32s: Only leave NX unset on segments used for modules")
Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/09fc73fe9c7423c6b4cf93f93df9bb0ed8eefab5.1597994047.git.christophe.leroy@csgroup.eu
2020-08-21 23:30:25 +10:00
Al Viro
70d65cd555 ppc: propagate the calling conventions change down to csum_partial_copy_generic()
... and get rid of the pointless fallback in the wrappers.  On error it used
to zero the unwritten area and calculate the csum of the entire thing.  Not
wanting to do it in assembler part had been very reasonable; doing that in
the first place, OTOH...  In case of an error the caller discards the data
we'd copied, along with whatever checksum it might've had.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-20 15:45:22 -04:00
Al Viro
c693cc4676 saner calling conventions for csum_and_copy_..._user()
All callers of these primitives will
	* discard anything we might've copied in case of error
	* ignore the csum value in case of error
	* always pass 0xffffffff as the initial sum, so the
resulting csum value (in case of success, that is) will never be 0.

That suggest the following calling conventions:
	* don't pass err_ptr - just return 0 on error.
	* don't bother with zeroing destination, etc. in case of error
	* don't pass the initial sum - just use 0xffffffff.

This commit does the minimal conversion in the instances of csum_and_copy_...();
the changes of actual asm code behind them are done later in the series.
Note that this asm code is often shared with csum_partial_copy_nocheck();
the difference is that csum_partial_copy_nocheck() passes 0 for initial
sum while csum_and_copy_..._user() pass 0xffffffff.  Fortunately, we are
free to pass 0xffffffff in all cases and subsequent patches will use that
freedom without any special comments.

A part that could be split off: parisc and uml/i386 claimed to have
csum_and_copy_to_user() instances of their own, but those were identical
to the generic one, so we simply drop them.  Not sure if it's worth
a separate commit...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-20 15:45:15 -04:00
Al Viro
cc44c17baf csum_partial_copy_nocheck(): drop the last argument
It's always 0.  Note that we theoretically could use ~0U as well -
result will be the same modulo 0xffff, _if_ the damn thing did the
right thing for any value of initial sum; later we'll make use of
that when convenient.

However, unlike csum_and_copy_..._user(), there are instances that
did not work for arbitrary initial sums; c6x is one such.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-20 15:45:14 -04:00
Al Viro
6e41c585e3 unify generic instances of csum_partial_copy_nocheck()
quite a few architectures have the same csum_partial_copy_nocheck() -
simply memcpy() the data and then return the csum of the copy.

hexagon, parisc, ia64, s390, um: explicitly spelled out that way.

arc, arm64, csky, h8300, m68k/nommu, microblaze, mips/GENERIC_CSUM, nds32,
nios2, openrisc, riscv, unicore32: end up picking the same thing spelled
out in lib/checksum.h (with varying amounts of perversions along the way).

everybody else (alpha, arm, c6x, m68k/mmu, mips/!GENERIC_CSUM, powerpc,
sh, sparc, x86, xtensa) have non-generic variants.  For all except c6x
the declaration is in their asm/checksum.h.  c6x uses the wrapper
from asm-generic/checksum.h that would normally lead to the lib/checksum.h
instance, but in case of c6x we end up using an asm function from arch/c6x
instead.

Screw that mess - have architectures with private instances define
_HAVE_ARCH_CSUM_AND_COPY in their asm/checksum.h and have the default
one right in net/checksum.h conditional on _HAVE_ARCH_CSUM_AND_COPY
*not* defined.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-20 15:45:14 -04:00
Vasant Hegde
90a9b102ed powerpc/pseries: Do not initiate shutdown when system is running on UPS
As per PAPR we have to look for both EPOW sensor value and event
modifier to identify the type of event and take appropriate action.

In LoPAPR v1.1 section 10.2.2 includes table 136 "EPOW Action Codes":

  SYSTEM_SHUTDOWN 3

  The system must be shut down. An EPOW-aware OS logs the EPOW error
  log information, then schedules the system to be shut down to begin
  after an OS defined delay internal (default is 10 minutes.)

Then in section 10.3.2.2.8 there is table 146 "Platform Event Log
Format, Version 6, EPOW Section", which includes the "EPOW Event
Modifier":

  For EPOW sensor value = 3
  0x01 = Normal system shutdown with no additional delay
  0x02 = Loss of utility power, system is running on UPS/Battery
  0x03 = Loss of system critical functions, system should be shutdown
  0x04 = Ambient temperature too high
  All other values = reserved

We have a user space tool (rtas_errd) on LPAR to monitor for
EPOW_SHUTDOWN_ON_UPS. Once it gets an event it initiates shutdown
after predefined time. It also starts monitoring for any new EPOW
events. If it receives "Power restored" event before predefined time
it will cancel the shutdown. Otherwise after predefined time it will
shutdown the system.

Commit 79872e3546 ("powerpc/pseries: All events of
EPOW_SYSTEM_SHUTDOWN must initiate shutdown") changed our handling of
the "on UPS/Battery" case, to immediately shutdown the system. This
breaks existing setups that rely on the userspace tool to delay
shutdown and let the system run on the UPS.

Fixes: 79872e3546 ("powerpc/pseries: All events of EPOW_SYSTEM_SHUTDOWN must initiate shutdown")
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
[mpe: Massage change log and add PAPR references]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200820061844.306460-1-hegdevasant@linux.vnet.ibm.com
2020-08-20 22:55:54 +10:00