19 Commits

Author SHA1 Message Date
Linus Torvalds
d38c07afc3 powerpc updates for 5.7
- A large series from Nick for 64-bit to further rework our exception vectors,
    and rewrite portions of the syscall entry/exit and interrupt return in C. The
    result is much easier to follow code that is also faster in general.
 
  - Cleanup of our ptrace code to split various parts out that had become badly
    intertwined with #ifdefs over the years.
 
  - Changes to our NUMA setup under the PowerVM hypervisor which should
    hopefully avoid non-sensical topologies which can lead to warnings from the
    workqueue code and other problems.
 
  - MAINTAINERS updates to remove some of our old orphan entries and update the
    status of others.
 
  - Quite a few other small changes and fixes all over the map.
 
 Thanks to:
   Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew Donnellan, Aneesh
   Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen Zhou, Christophe JAILLET,
   Christophe Leroy, Christoph Hellwig, Clement Courbet, Daniel Axtens, David
   Gibson, Douglas Miller, Fabiano Rosas, Fangrui Song, Ganesh Goudar, Gautham R.
   Shenoy, Greg Kroah-Hartman, Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie
   Halip, Jan Kara, Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger,
   Laurentiu Tudor, Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh
   Salgaonkar, Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira,
   Michael Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan
   Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers,
   Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat, Rasmus Villemoes, Ravi
   Bangoria, Roman Bolshakov, Sam Bobroff, Sandipan Das, Santosh S, Sedat Dilek,
   Segher Boessenkool, Shilpasri G Bhat, Sourabh Jain, Srikar Dronamraju, Stephen
   Rothwell, Tyrel Datwyler, Vaibhav Jain, YueHaibing.
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Merge tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Slightly late as I had to rebase mid-week to insert a bug fix:

   - A large series from Nick for 64-bit to further rework our exception
     vectors, and rewrite portions of the syscall entry/exit and
     interrupt return in C. The result is much easier to follow code
     that is also faster in general.

   - Cleanup of our ptrace code to split various parts out that had
     become badly intertwined with #ifdefs over the years.

   - Changes to our NUMA setup under the PowerVM hypervisor which should
     hopefully avoid non-sensical topologies which can lead to warnings
     from the workqueue code and other problems.

   - MAINTAINERS updates to remove some of our old orphan entries and
     update the status of others.

   - Quite a few other small changes and fixes all over the map.

  Thanks to: Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew
  Donnellan, Aneesh Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen
  Zhou, Christophe JAILLET, Christophe Leroy, Christoph Hellwig, Clement
  Courbet, Daniel Axtens, David Gibson, Douglas Miller, Fabiano Rosas,
  Fangrui Song, Ganesh Goudar, Gautham R. Shenoy, Greg Kroah-Hartman,
  Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie Halip, Jan Kara,
  Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger, Laurentiu Tudor,
  Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh Salgaonkar,
  Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira, Michael
  Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan
  Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick
  Desaulniers, Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat,
  Rasmus Villemoes, Ravi Bangoria, Roman Bolshakov, Sam Bobroff,
  Sandipan Das, Santosh S, Sedat Dilek, Segher Boessenkool, Shilpasri G
  Bhat, Sourabh Jain, Srikar Dronamraju, Stephen Rothwell, Tyrel
  Datwyler, Vaibhav Jain, YueHaibing"

* tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits)
  powerpc: Make setjmp/longjmp signature standard
  powerpc/cputable: Remove unnecessary copy of cpu_spec->oprofile_type
  powerpc: Suppress .eh_frame generation
  powerpc: Drop -fno-dwarf2-cfi-asm
  powerpc/32: drop unused ISA_DMA_THRESHOLD
  powerpc/powernv: Add documentation for the opal sensor_groups sysfs interfaces
  selftests/powerpc: Fix try-run when source tree is not writable
  powerpc/vmlinux.lds: Explicitly retain .gnu.hash
  powerpc/ptrace: move ptrace_triggered() into hw_breakpoint.c
  powerpc/ptrace: create ppc_gethwdinfo()
  powerpc/ptrace: create ptrace_get_debugreg()
  powerpc/ptrace: split out ADV_DEBUG_REGS related functions.
  powerpc/ptrace: move register viewing functions out of ptrace.c
  powerpc/ptrace: split out TRANSACTIONAL_MEM related functions.
  powerpc/ptrace: split out SPE related functions.
  powerpc/ptrace: split out ALTIVEC related functions.
  powerpc/ptrace: split out VSX related functions.
  powerpc/ptrace: drop PARAMETER_SAVE_AREA_OFFSET
  powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64
  powerpc/ptrace: remove unused header includes
  ...
2020-04-05 11:12:59 -07:00
Christophe Leroy
af92bad615 powerpc/kasan: Fix kasan_remap_early_shadow_ro()
At the moment kasan_remap_early_shadow_ro() does nothing, because
k_end is 0 and k_cur < 0 is always true.

Change the test to k_cur != k_end, as done in
kasan_init_shadow_page_tables()

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Fixes: cbd18991e24f ("powerpc/mm: Fix an Oops in kasan_mmu_init()")
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4e7b56865e01569058914c991143f5961b5d4719.1583507333.git.christophe.leroy@c-s.fr
2020-03-25 12:09:27 +11:00
Christophe Leroy
af3d0a6869 powerpc/kasan: Fix shadow memory protection with CONFIG_KASAN_VMALLOC
With CONFIG_KASAN_VMALLOC, new page tables are created at the time
shadow memory for vmalloc area is unmapped. If some parts of the
page table still have entries to the zero page shadow memory, the
entries are wrongly marked RW.

With CONFIG_KASAN_VMALLOC, almost the entire kernel address space
is managed by KASAN. To make it simple, just create KASAN page tables
for the entire kernel space at kasan_init(). That doesn't use much
more space, and that's anyway already done for hash platforms.

Fixes: 3d4247fcc938 ("powerpc/32: Add support of KASAN_VMALLOC")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ef5248fc1f496c6b0dfdb59380f24968f25f75c5.1583513368.git.christophe.leroy@c-s.fr
2020-03-13 21:10:37 +11:00
Michael Ellerman
819723a8a2 Merge branch 'fixes' into next
Merge in our fixes branch. In particular we want to merge the TM and KUAP fixes,
so we can add selftests for them in next.
2020-03-10 15:16:42 +11:00
Christophe Leroy
0b1c524caa powerpc/32: refactor pmd_offset(pud_offset(pgd_offset...
At several places pmd pointer is retrieved through the same action:

	pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr);

or

	pmd = pmd_offset(pud_offset(pgd_offset_k(addr), addr), addr);

Refactor this by implementing two helpers pmd_ptr() and pmd_ptr_k()

This will help when adding the p4d level.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7b065c5be35726af4066cab238ee35cabceda1fa.1578558199.git.christophe.leroy@c-s.fr
2020-02-26 10:34:40 +11:00
Christophe Leroy
232ca1eeca powerpc/32s: Fix DSI and ISI exceptions for CONFIG_VMAP_STACK
hash_page() needs to read page tables from kernel memory. When entire
kernel memory is mapped by BATs, which is normally the case when
CONFIG_STRICT_KERNEL_RWX is not set, it works even if the page hosting
the page table is not referenced in the MMU hash table.

However, if the page where the page table resides is not covered by
a BAT, a DSI fault can be encountered from hash_page(), and it loops
forever. This can happen when CONFIG_STRICT_KERNEL_RWX is selected
and the alignment of the different regions is too small to allow
covering the entire memory with BATs. This also happens when
CONFIG_DEBUG_PAGEALLOC is selected or when booting with 'nobats'
flag.

Also, if the page containing the kernel stack is not present in the
MMU hash table, registers cannot be saved and a recursive DSI fault
is encountered.

To allow hash_page() to properly do its job at all time and load the
MMU hash table whenever needed, it must run with data MMU disabled.
This means it must be called before re-enabling data MMU. To allow
this, registers clobbered by hash_page() and create_hpte() have to
be saved in the thread struct together with SRR0, SSR1, DAR and DSISR.
It is also necessary to ensure that DSI prolog doesn't overwrite
regs saved by prolog of the current running exception. That means:
- DSI can only use SPRN_SPRG_SCRATCH0
- Exceptions must free SPRN_SPRG_SCRATCH0 before writing to the stack.

This also fixes the Oops reported by Erhard when create_hpte() is
called by add_hash_page().

Due to prolog size increase, a few more exceptions had to get split
in two parts.

Fixes: cd08f109e262 ("powerpc/32s: Enable CONFIG_VMAP_STACK")
Reported-by: Erhard F. <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Tested-by: Erhard F. <erhard_f@mailbox.org>
Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206501
Link: https://lore.kernel.org/r/64a4aa44686e9fd4b01333401367029771d9b231.1581761633.git.christophe.leroy@c-s.fr
2020-02-18 21:31:11 +11:00
Christophe Leroy
4119622488 powerpc/32s: Fix kasan_early_hash_table() for CONFIG_VMAP_STACK
On book3s/32 CPUs that are handling MMU through a hash table,
MMU_init_hw() function was adapted for VMAP_STACK in order to
handle virtual addresses instead of physical addresses in the
low level hash functions.

When using KASAN, the same adaptations are required for the
early hash table set up by kasan_early_hash_table() function.

Fixes: cd08f109e262 ("powerpc/32s: Enable CONFIG_VMAP_STACK")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fc8390a33c2a470105f01abbcbdc7916c30c0a54.1580301269.git.christophe.leroy@c-s.fr
2020-01-30 23:47:09 +11:00
Christophe Leroy
21613cfad1 powerpc/32: Reuse orphaned memblocks in kasan_init_shadow_page_tables()
If concurrent PMD population has happened, re-use orphaned memblocks.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b29ffffb9206dc14541fa420c17604240728041b.1579024426.git.christophe.leroy@c-s.fr
2020-01-27 22:37:45 +11:00
Christophe Leroy
509cd3f2b4 powerpc/32: Simplify KASAN init
Since kasan_init_region() is not used anymore for modules,
KASAN init is done while slab_is_available() is false.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/84b27bf08b41c8343efd88e10f2eccd8e9f85593.1579024426.git.christophe.leroy@c-s.fr
2020-01-27 22:37:45 +11:00
Christophe Leroy
47febbeeec powerpc/32: Force KASAN_VMALLOC for modules
Unloading/Reloading of modules seems to fail with KASAN_VMALLOC
but works properly with it.

Force selection of KASAN_VMALLOC when MODULES are selected, and
drop module_alloc() which was dedicated to KASAN for modules.

Reported-by: <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=205283
Link: https://lore.kernel.org/r/f909da11aecb59ab7f32ba01fae6f356eaa4d7bc.1579024426.git.christophe.leroy@c-s.fr
2020-01-27 22:37:41 +11:00
Christophe Leroy
3d4247fcc9 powerpc/32: Add support of KASAN_VMALLOC
Add support of KASAN_VMALLOC on PPC32.

To allow this, the early shadow covering the VMALLOC space
need to be removed once high_memory var is set and before
freeing memblock.

And the VMALLOC area need to be aligned such that boundaries
are covered by a full shadow page.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/031dec5487bde9b2181c8b3c9800e1879cf98c1a.1579024426.git.christophe.leroy@c-s.fr
2020-01-27 22:37:33 +11:00
Christophe Leroy
cbd18991e2 powerpc/mm: Fix an Oops in kasan_mmu_init()
Uncompressing Kernel Image ... OK
   Loading Device Tree to 01ff7000, end 01fff74f ... OK
[    0.000000] printk: bootconsole [udbg0] enabled
[    0.000000] BUG: Unable to handle kernel data access at 0xf818c000
[    0.000000] Faulting instruction address: 0xc0013c7c
[    0.000000] Thread overran stack, or stack corrupted
[    0.000000] Oops: Kernel access of bad area, sig: 11 [#1]
[    0.000000] BE PAGE_SIZE=16K PREEMPT
[    0.000000] Modules linked in:
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.3.0-rc4-s3k-dev-00743-g5abe4a3e8fd3-dirty #2080
[    0.000000] NIP:  c0013c7c LR: c0013310 CTR: 00000000
[    0.000000] REGS: c0c5ff38 TRAP: 0300   Not tainted  (5.3.0-rc4-s3k-dev-00743-g5abe4a3e8fd3-dirty)
[    0.000000] MSR:  00001032 <ME,IR,DR,RI>  CR: 99033955  XER: 80002100
[    0.000000] DAR: f818c000 DSISR: 82000000
[    0.000000] GPR00: c0013310 c0c5fff0 c0ad6ac0 c0c600c0 f818c031 82000000 00000000 ffffffff
[    0.000000] GPR08: 00000000 f1f1f1f1 c0013c2c c0013304 99033955 00400008 00000000 07ff9598
[    0.000000] GPR16: 00000000 07ffb94c 00000000 00000000 00000000 00000000 00000000 f818cfb2
[    0.000000] GPR24: 00000000 00000000 00001000 ffffffff 00000000 c07dbf80 00000000 f818c000
[    0.000000] NIP [c0013c7c] do_page_fault+0x50/0x904
[    0.000000] LR [c0013310] handle_page_fault+0xc/0x38
[    0.000000] Call Trace:
[    0.000000] Instruction dump:
[    0.000000] be010080 91410014 553fe8fe 3d40c001 3d20f1f1 7d800026 394a3c2c 3fffe000
[    0.000000] 6129f1f1 900100c4 9181007c 91410018 <913f0000> 3d2001f4 6129f4f4 913f0004

Don't map the early shadow page read-only yet when creating the new
page tables for the real shadow memory, otherwise the memblock
allocations that immediately follows to create the real shadow pages
that are about to replace the early shadow page trigger a page fault
if they fall into the region being worked on at the moment.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support")
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fe86886fb8db44360417cee0dc515ad47ca6ef72.1566382750.git.christophe.leroy@c-s.fr
2019-09-21 08:36:53 +10:00
Christophe Leroy
4c0f5d1eb4 powerpc/mm: Add a helper to select PAGE_KERNEL_RO or PAGE_READONLY
In a couple of places there is a need to select whether read-only
protection of shadow pages is performed with PAGE_KERNEL_RO or with
PAGE_READONLY.

Add a helper to avoid duplicating the choice.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/9f33f44b9cd741c4a02b3dce7b8ef9438fe2cd2a.1566382750.git.christophe.leroy@c-s.fr
2019-09-21 08:36:53 +10:00
Christophe Leroy
663c0c9496 powerpc/kasan: Fix shadow area set up for modules.
When loading modules, from time to time an Oops is encountered during
the init of shadow area for globals. This is due to the last page not
always being mapped depending on the exact distance between the start
and the end of the shadow area and the alignment with the page
addresses.

Fix this by aligning the starting address with the page address.

Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support")
Cc: stable@vger.kernel.org # v5.2+
Reported-by: Erhard F. <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4f887e9b77d0d725cbb52035c7ece485c1c5fc14.1565361881.git.christophe.leroy@c-s.fr
2019-08-20 21:22:11 +10:00
Christophe Leroy
45ff3c5595 powerpc/kasan: Fix parallel loading of modules.
Parallel loading of modules may lead to bad setup of shadow page table
entries.

First, lets align modules so that two modules never share the same
shadow page.

Second, ensure that two modules cannot allocate two page tables for
the same PMD entry at the same time. This is done by using
init_mm.page_table_lock in the same way as __pte_alloc_kernel()

Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c97284f912128cbc3f2fe09d68e90e65fb3e6026.1565361876.git.christophe.leroy@c-s.fr
2019-08-20 21:22:11 +10:00
Christophe Leroy
d7e23b887f powerpc/kasan: fix early boot failure on PPC32
Due to commit 4a6d8cf90017 ("powerpc/mm: don't use pte_alloc_kernel()
until slab is available on PPC32"), pte_alloc_kernel() cannot be used
during early KASAN init.

Fix it by using memblock_alloc() instead.

Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support")
Cc: stable@vger.kernel.org # v5.2+
Reported-by: Erhard F. <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/da89670093651437f27d2975224712e0a130b055.1564552796.git.christophe.leroy@c-s.fr
2019-07-31 22:02:52 +10:00
Christophe Leroy
da3a3b0a0e powerpc/32s: map kasan zero shadow with PAGE_READONLY instead of PAGE_KERNEL_RO
For hash32, the zero shadow page gets mapped with PAGE_READONLY instead
of PAGE_KERNEL_RO, because the PP bits don't provide a RO kernel, so
PAGE_KERNEL_RO is equivalent to PAGE_KERNEL. By using PAGE_READONLY,
the page is RO for both kernel and user, but this is not a security issue
as it contains only zeroes.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:26 +10:00
Christophe Leroy
215b823707 powerpc/32s: set up an early static hash table for KASAN.
KASAN requires early activation of hash table, before memblock()
functions are available.

This patch implements an early hash_table statically defined in
__initdata.

During early boot, a single page table is used.

For hash32, when doing the final init, one page table is allocated
for each PGD entry because of the _PAGE_HASHPTE flag which can't be
common to several virt pages. This is done after memblock get
available but before switching to the final hash table, otherwise
there are issues with TLB flushing due to the shared entries.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:26 +10:00
Christophe Leroy
2edb16efc8 powerpc/32: Add KASAN support
This patch adds KASAN support for PPC32. The following patch
will add an early activation of hash table for book3s. Until
then, a warning will be raised if trying to use KASAN on an
hash 6xx.

To support KASAN, this patch initialises that MMU mapings for
accessing to the KASAN shadow area defined in a previous patch.

An early mapping is set as soon as the kernel code has been
relocated at its definitive place.

Then the definitive mapping is set once paging is initialised.

For modules, the shadow area is allocated at module_alloc().

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:26 +10:00