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SYS_SUPPORTS_HUGETLBFS config has duplicate definitions on platforms
that subscribe it. Instead, just make it a generic option which can be
selected on applicable platforms.
Also rename it as ARCH_SUPPORTS_HUGETLBFS instead. This reduces code
duplication and makes it cleaner.
Link: https://lkml.kernel.org/r/1617259448-22529-3-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com> [riscv]
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull swiotlb updates from Konrad Rzeszutek Wilk:
"Christoph Hellwig has taken a cleaver and trimmed off the not-needed
code and nicely folded duplicate code in the generic framework.
This lays the groundwork for more work to add extra DMA-backend-ish in
the future. Along with that some bug-fixes to make this a nice working
package"
* 'stable/for-linus-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
swiotlb: don't override user specified size in swiotlb_adjust_size
swiotlb: Fix the type of index
swiotlb: Make SWIOTLB_NO_FORCE perform no allocation
ARM: Qualify enabling of swiotlb_init()
swiotlb: remove swiotlb_nr_tbl
swiotlb: dynamically allocate io_tlb_default_mem
swiotlb: move global variables into a new io_tlb_mem structure
xen-swiotlb: remove the unused size argument from xen_swiotlb_fixup
xen-swiotlb: split xen_swiotlb_init
swiotlb: lift the double initialization protection from xen-swiotlb
xen-swiotlb: remove xen_io_tlb_start and xen_io_tlb_nslabs
xen-swiotlb: remove xen_set_nslabs
xen-swiotlb: use io_tlb_end in xen_swiotlb_dma_supported
xen-swiotlb: use is_swiotlb_buffer in is_xen_swiotlb_buffer
swiotlb: split swiotlb_tbl_sync_single
swiotlb: move orig addr and size validation into swiotlb_bounce
swiotlb: remove the alloc_size parameter to swiotlb_tbl_unmap_single
powerpc/svm: stop using io_tlb_start
Trace memory is cleared and the corresponding dcache lines
are flushed after allocation. However, this should not be
done using the PFN. This adds the missing conversion to
virtual address.
Fixes: 2ac02e5ecec0 ("powerpc/mm: Remove dcache flush from memory remove.")
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
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/20210501160254.1179831-1-sandipan@linux.ibm.com
This code was only used by the vfio-nvlink2 code, which itself had no
proper use. Drop this huge chunk of code build into every powernv
or generic build.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210326061311.1497642-3-hch@lst.de
- Enable KFENCE for 32-bit.
- Implement EBPF for 32-bit.
- Convert 32-bit to do interrupt entry/exit in C.
- Convert 64-bit BookE to do interrupt entry/exit in C.
- Changes to our signal handling code to use user_access_begin/end() more extensively.
- Add support for time namespaces (CONFIG_TIME_NS)
- A series of fixes that allow us to reenable STRICT_KERNEL_RWX.
- Other smaller features, fixes & cleanups.
Thanks to: Alexey Kardashevskiy, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V,
Athira Rajeev, Bhaskar Chowdhury, Bixuan Cui, Cédric Le Goater, Chen Huang, Chris
Packham, Christophe Leroy, Christopher M. Riedl, Colin Ian King, Dan Carpenter, Daniel
Axtens, Daniel Henrique Barboza, David Gibson, Davidlohr Bueso, Denis Efremov,
dingsenjie, Dmitry Safonov, Dominic DeMarco, Fabiano Rosas, Ganesh Goudar, Geert
Uytterhoeven, Geetika Moolchandani, Greg Kurz, Guenter Roeck, Haren Myneni, He Ying,
Jiapeng Chong, Jordan Niethe, Laurent Dufour, Lee Jones, Leonardo Bras, Li Huafei,
Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Nathan Chancellor, Nathan
Lynch, Nicholas Piggin, Oliver O'Halloran, Paul Menzel, Pu Lehui, Randy Dunlap, Ravi
Bangoria, Rosen Penev, Russell Currey, Santosh Sivaraj, Sebastian Andrzej Siewior,
Segher Boessenkool, Shivaprasad G Bhat, Srikar Dronamraju, Stephen Rothwell, Thadeu Lima
de Souza Cascardo, Thomas Gleixner, Tony Ambardar, Tyrel Datwyler, Vaibhav Jain,
Vincenzo Frascino, Xiongwei Song, Yang Li, Yu Kuai, Zhang Yunkai.
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Merge tag 'powerpc-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
- Enable KFENCE for 32-bit.
- Implement EBPF for 32-bit.
- Convert 32-bit to do interrupt entry/exit in C.
- Convert 64-bit BookE to do interrupt entry/exit in C.
- Changes to our signal handling code to use user_access_begin/end()
more extensively.
- Add support for time namespaces (CONFIG_TIME_NS)
- A series of fixes that allow us to reenable STRICT_KERNEL_RWX.
- Other smaller features, fixes & cleanups.
Thanks to Alexey Kardashevskiy, Andreas Schwab, Andrew Donnellan, Aneesh
Kumar K.V, Athira Rajeev, Bhaskar Chowdhury, Bixuan Cui, Cédric Le
Goater, Chen Huang, Chris Packham, Christophe Leroy, Christopher M.
Riedl, Colin Ian King, Dan Carpenter, Daniel Axtens, Daniel Henrique
Barboza, David Gibson, Davidlohr Bueso, Denis Efremov, dingsenjie,
Dmitry Safonov, Dominic DeMarco, Fabiano Rosas, Ganesh Goudar, Geert
Uytterhoeven, Geetika Moolchandani, Greg Kurz, Guenter Roeck, Haren
Myneni, He Ying, Jiapeng Chong, Jordan Niethe, Laurent Dufour, Lee
Jones, Leonardo Bras, Li Huafei, Madhavan Srinivasan, Mahesh Salgaonkar,
Masahiro Yamada, Nathan Chancellor, Nathan Lynch, Nicholas Piggin,
Oliver O'Halloran, Paul Menzel, Pu Lehui, Randy Dunlap, Ravi Bangoria,
Rosen Penev, Russell Currey, Santosh Sivaraj, Sebastian Andrzej Siewior,
Segher Boessenkool, Shivaprasad G Bhat, Srikar Dronamraju, Stephen
Rothwell, Thadeu Lima de Souza Cascardo, Thomas Gleixner, Tony Ambardar,
Tyrel Datwyler, Vaibhav Jain, Vincenzo Frascino, Xiongwei Song, Yang Li,
Yu Kuai, and Zhang Yunkai.
* tag 'powerpc-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (302 commits)
powerpc/signal32: Fix erroneous SIGSEGV on RT signal return
powerpc: Avoid clang uninitialized warning in __get_user_size_allowed
powerpc/papr_scm: Mark nvdimm as unarmed if needed during probe
powerpc/kvm: Fix build error when PPC_MEM_KEYS/PPC_PSERIES=n
powerpc/kasan: Fix shadow start address with modules
powerpc/kernel/iommu: Use largepool as a last resort when !largealloc
powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs
powerpc/44x: fix spelling mistake in Kconfig "varients" -> "variants"
powerpc/iommu: Annotate nested lock for lockdep
powerpc/iommu: Do not immediately panic when failed IOMMU table allocation
powerpc/iommu: Allocate it_map by vmalloc
selftests/powerpc: remove unneeded semicolon
powerpc/64s: remove unneeded semicolon
powerpc/eeh: remove unneeded semicolon
powerpc/selftests: Add selftest to test concurrent perf/ptrace events
powerpc/selftests/perf-hwbreak: Add testcases for 2nd DAWR
powerpc/selftests/perf-hwbreak: Coalesce event creation code
powerpc/selftests/ptrace-hwbreak: Add testcases for 2nd DAWR
powerpc/configs: Add IBMVNIC to some 64-bit configs
selftests/powerpc: Add uaccess flush test
...
Pull coredump updates from Al Viro:
"Just a couple of patches this cycle: use of seek + write instead of
expanding truncate and minor header cleanup"
* 'work.coredump' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
coredump.h: move CONFIG_COREDUMP-only stuff inside the ifdef
coredump: don't bother with do_truncate()
Pull vfs inode type handling updates from Al Viro:
"We should never change the type bits of ->i_mode or the method tables
(->i_op and ->i_fop) of a live inode.
Unfortunately, not all filesystems took care to prevent that"
* 'work.inode-type-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
spufs: fix bogosity in S_ISGID handling
9p: missing chunk of "fs/9p: Don't update file type when updating file attributes"
openpromfs: don't do unlock_new_inode() until the new inode is set up
hostfs_mknod(): don't bother with init_special_inode()
cifs: have cifs_fattr_to_inode() refuse to change type on live inode
cifs: have ->mkdir() handle race with another client sanely
do_cifs_create(): don't set ->i_mode of something we had not created
gfs2: be careful with inode refresh
ocfs2_inode_lock_update(): make sure we don't change the type bits of i_mode
orangefs_inode_is_stale(): i_mode type bits do *not* form a bitmap...
vboxsf: don't allow to change the inode type
afs: Fix updating of i_mode due to 3rd party change
ceph: don't allow type or device number to change on non-I_NEW inodes
ceph: fix up error handling with snapdirs
new helper: inode_wrong_type()
In case an nvdimm is found to be unarmed during probe then set its
NDD_UNARMED flag before nvdimm_create(). This would enforce a
read-only access to the ndimm region. Presently even if an nvdimm is
unarmed its not marked as read-only on ppc64 guests.
The patch updates papr_scm_nvdimm_init() to force query of nvdimm
health via __drc_pmem_query_health() and if nvdimm is found to be
unarmed then set the nvdimm flag ND_UNARMED for nvdimm_create().
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
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/20210329113103.476760-1-vaibhav@linux.ibm.com
Most platforms allocate IOMMU table structures (specifically it_map)
at the boot time and when this fails - it is a valid reason for panic().
However the powernv platform allocates it_map after a device is returned
to the host OS after being passed through and this happens long after
the host OS booted. It is quite possible to trigger the it_map allocation
panic() and kill the host even though it is not necessary - the host OS
can still use the DMA bypass mode (requires a tiny fraction of it_map's
memory) and even if that fails, the host OS is runnnable as it was without
the device for which allocating it_map causes the panic.
Instead of immediately crashing in a powernv/ioda2 system, this prints
an error and continues. All other platforms still call panic().
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Leonardo Bras <leobras.c@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210216033307.69863-3-aik@ozlabs.ru
Eliminate the following coccicheck warning:
./arch/powerpc/platforms/powernv/setup.c:160:2-3: Unneeded semicolon
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1612236877-104974-1-git-send-email-yang.lee@linux.alibaba.com
On a kernel config with ALTIVEC=y and PPC_FPU not set/enabled,
there are build errors:
drivers/cpufreq/pmac32-cpufreq.c:262:2: error: implicit declaration of function 'enable_kernel_fp' [-Werror,-Wimplicit-function-declaration]
enable_kernel_fp();
../arch/powerpc/lib/sstep.c: In function 'do_vec_load':
../arch/powerpc/lib/sstep.c:637:3: error: implicit declaration of function 'put_vr' [-Werror=implicit-function-declaration]
637 | put_vr(rn, &u.v);
| ^~~~~~
../arch/powerpc/lib/sstep.c: In function 'do_vec_store':
../arch/powerpc/lib/sstep.c:660:3: error: implicit declaration of function 'get_vr'; did you mean 'get_oc'? [-Werror=implicit-function-declaration]
660 | get_vr(rn, &u.v);
| ^~~~~~
In theory ALTIVEC is independent of PPC_FPU but in practice nobody
is going to build such a machine, so make ALTIVEC require PPC_FPU
by selecting it.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210421210647.20836-1-rdunlap@infradead.org
As of today, if the DDW is big enough to fit (1 << MAX_PHYSMEM_BITS)
it's possible to use direct DMA mapping even with pmem region.
But, if that happens, the window size (len) is set to (MAX_PHYSMEM_BITS
- page_shift) instead of MAX_PHYSMEM_BITS, causing a pagesize times
smaller DDW to be created, being insufficient for correct usage.
Fix this so the correct window size is used in this case.
Fixes: bf6e2d562bbc4 ("powerpc/dma: Fallback to dma_ops when persistent memory present")
Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210420045404.438735-1-leobras.c@gmail.com
RCU complains about us calling printk() from an offline CPU:
=============================
WARNING: suspicious RCU usage
5.12.0-rc7-02874-g7cf90e481cb8 #1 Not tainted
-----------------------------
kernel/locking/lockdep.c:3568 RCU-list traversed in non-reader section!!
other info that might help us debug this:
RCU used illegally from offline CPU!
rcu_scheduler_active = 2, debug_locks = 1
no locks held by swapper/0/0.
stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.12.0-rc7-02874-g7cf90e481cb8 #1
Call Trace:
dump_stack+0xec/0x144 (unreliable)
lockdep_rcu_suspicious+0x124/0x144
__lock_acquire+0x1098/0x28b0
lock_acquire+0x128/0x600
_raw_spin_lock_irqsave+0x6c/0xc0
down_trylock+0x2c/0x70
__down_trylock_console_sem+0x60/0x140
vprintk_emit+0x1a8/0x4b0
vprintk_func+0xcc/0x200
printk+0x40/0x54
pseries_cpu_offline_self+0xc0/0x120
arch_cpu_idle_dead+0x54/0x70
do_idle+0x174/0x4a0
cpu_startup_entry+0x38/0x40
rest_init+0x268/0x388
start_kernel+0x748/0x790
start_here_common+0x1c/0x614
Which happens because by the time we get to rtas_stop_self() we are
already offline. In addition the message can be spammy, and is not that
helpful for users, so remove it.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210418135413.1204031-1-mpe@ellerman.id.au
Currently, neither the vio_bus or vio_driver structures provide support
for a shutdown() routine.
Add support for shutdown() by allowing drivers to provide a
implementation via function pointer in their vio_driver struct and
provide a proper implementation in the driver template for the vio_bus
that calls a vio drivers shutdown() if defined.
In the case that no shutdown() is defined by a vio driver and a kexec is
in progress we implement a big hammer that calls remove() to ensure no
further DMA for the devices is possible.
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210402001325.939668-1-tyreld@linux.ibm.com
The RTAS set-indicator call, when attempting to UNISOLATE a DRC that is
already UNISOLATED or CONFIGURED, returns RTAS_OK and does nothing else
for both QEMU and phyp. This gives us an opportunity to use this
behavior to signal the hypervisor layer when an error during device
removal happens, allowing it to do a proper error handling, while not
breaking QEMU/phyp implementations that don't have this support.
This patch introduces this idea by unisolating all CPU DRCs that failed
to be removed by dlpar_cpu_remove_by_index(), when handling the
PSERIES_HP_ELOG_ID_DRC_INDEX event. This is being done for this event
only because its the only CPU removal event QEMU uses, and there's no
need at this moment to add this mechanism for phyp only code.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210416210216.380291-3-danielhb413@gmail.com
Next patch will execute a set-indicator call in hotplug-cpu.c.
Create a dlpar_unisolate_drc() helper to avoid spreading more
rtas_set_indicator() calls outside of dlpar.c.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210416210216.380291-2-danielhb413@gmail.com
The pci_bus->bridge reference may no longer be valid after
pci_bus_remove() resulting in passing a bad value to device_unregister()
for the associated bridge device.
Store the host_bridge reference in a separate variable prior to
pci_bus_remove().
Fixes: 7340056567e3 ("powerpc/pci: Reorder pci bus/bridge unregistration during PHB removal")
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210211182435.47968-1-tyreld@linux.ibm.com
When I changed the rc variable to be long rather than int64_t I
neglected to update the printk(), leading to a build break:
arch/powerpc/platforms/pseries/papr_scm.c: In function 'papr_scm_pmem_flush':
arch/powerpc/platforms/pseries/papr_scm.c:144:26: warning: format
'%lld' expects argument of type 'long long int', but argument 3 has
type 'long int' [-Wformat=]
Fixes: 75b7c05ebf90 ("powerpc/papr_scm: Implement support for H_SCM_FLUSH hcall")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210416111209.765444-2-mpe@ellerman.id.au
Fix sparse warnings:
arch/powerpc/platforms/pseries/rtas-fadump.c:250:6: warning:
symbol 'rtas_fadump_set_regval' was not declared. Should it be static?
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210408062012.85973-1-pulehui@huawei.com
The sparse tool complains as follows:
arch/powerpc/platforms/powernv/opal-core.c:74:16: warning:
symbol 'mpipl_kobj' was not declared.
This symbol is not used outside of opal-core.c, so marks it static.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210409063855.57347-1-cuibixuan@huawei.com
The sparse tool complains as follows:
arch/powerpc/platforms/pseries/pmem.c:142:27: warning:
symbol 'drc_pmem_match' was not declared. Should it be static?
This symbol is not used outside of pmem.c, so this
commit marks it static.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210409090114.59396-1-cuibixuan@huawei.com
The sparse tool complains as follows:
arch/powerpc/platforms/pseries/hvCall_inst.c:29:1: warning:
symbol '__pcpu_scope_hcall_stats' was not declared. Should it be static?
This symbol is not used outside of hvCall_inst.c, so this
commit marks it static.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210409090109.59347-1-cuibixuan@huawei.com
According to LoPAR, ibm,query-pe-dma-window output named "IO Page Sizes"
will let the OS know all possible pagesizes that can be used for creating a
new DDW.
Currently Linux will only try using 3 of the 8 available options:
4K, 64K and 16M. According to LoPAR, Hypervisor may also offer 32M, 64M,
128M, 256M and 16G.
Enabling bigger pages would be interesting for direct mapping systems
with a lot of RAM, while using less TCE entries.
Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210408201915.174217-1-leobras.c@gmail.com
Many architectures duplicate similar shell scripts.
This commit converts powerpc to use scripts/syscalltbl.sh. This also
unifies syscall_table_32.h and syscall_table_c32.h.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210301153019.362742-1-masahiroy@kernel.org
Add support for ND_REGION_ASYNC capability if the device tree
indicates 'ibm,hcall-flush-required' property in the NVDIMM node.
Flush is done by issuing H_SCM_FLUSH hcall to the hypervisor.
If the flush request failed, the hypervisor is expected to
to reflect the problem in the subsequent nvdimm H_SCM_HEALTH call.
This patch prevents mmap of namespaces with MAP_SYNC flag if the
nvdimm requires an explicit flush[1].
References:
[1] https://github.com/avocado-framework-tests/avocado-misc-tests/blob/master/memory/ndctl.py.data/map_sync.c
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Use unsigned long / long instead of uint64_t/int64_t]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/161703936121.36.7260632399582101498.stgit@e1fbed493c87
Eliminate the following coccicheck warning:
./arch/powerpc/platforms/pseries/lpar.c:1633:2-3: Unneeded semicolon
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1617672785-81372-1-git-send-email-yang.lee@linux.alibaba.com
Let the memory removed from the linear mapping to be used for the trace
buffers be mmaped. This is a useful way of providing cache-inhibited
memory for the alignment_handler selftest.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: make memtrace_mmap() static as noticed by lkp@intel.com]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210225032108.1458352-1-jniethe5@gmail.com
The flags argument to plpar_pte_protect() (aka. H_PROTECT), includes
the key in bits 9-13, but currently we always set those bits to zero.
In the past that hasn't been a problem because we always used key 0
for the kernel, and updateboltedpp() is only used for kernel mappings.
However since commit d94b827e89dc ("powerpc/book3s64/kuap: Use Key 3
for kernel mapping with hash translation") we are now inadvertently
changing the key (to zero) when we call plpar_pte_protect().
That hasn't broken anything because updateboltedpp() is only used for
STRICT_KERNEL_RWX, which is currently disabled on 64s due to other
bugs.
But we want to fix that, so first we need to pass the key correctly to
plpar_pte_protect(). We can't pass our newpp value directly in, we
have to convert it into the form expected by the hcall.
The hcall we're using here is H_PROTECT, which is specified in section
14.5.4.1.6 of LoPAPR v1.1.
It takes a `flags` parameter, and the description for flags says:
* flags: AVPN, pp0, pp1, pp2, key0-key4, n, and for the CMO
option: CMO Option flags as defined in Table 189‚
If you then go to the start of the parent section, 14.5.4.1, on page
405, it says:
Register Linkage (For hcall() tokens 0x04 - 0x18)
* On Call
* R3 function call token
* R4 flags (see Table 178‚ “Page Frame Table Access flags field
definition‚” on page 401)
Then you have to go to section 14.5.3, and on page 394 there is a list
of hcalls and their tokens (table 176), and there you can see that
H_PROTECT == 0x18.
Finally you can look at table 178, on page 401, where it specifies the
layout of the bits for the key:
Bit Function
-----------------
50-54 | key0-key4
Those are big-endian bit numbers, converting to normal bit numbers you
get bits 9-13, or 0x3e00.
In the kernel we have:
#define HPTE_R_KEY_HI ASM_CONST(0x3000000000000000)
#define HPTE_R_KEY_LO ASM_CONST(0x0000000000000e00)
So the LO bits of newpp are already in the right place, and the HI
bits need to be shifted down by 48.
Fixes: d94b827e89dc ("powerpc/book3s64/kuap: Use Key 3 for kernel mapping with hash translation")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210331003845.216246-2-mpe@ellerman.id.au
The vio bus is a fake bus, which we use on pseries LPARs (guests) to
discover devices provided by the hypervisor. There's no need or sense
in creating the vio bus on bare metal systems.
Which is why commit 4336b9337824 ("powerpc/pseries: Make vio and
ibmebus initcalls pseries specific") made the initialisation of the
vio bus only happen in LPARs.
However as a result of that commit we now see errors at boot on bare
metal systems:
Driver 'hvc_console' was unable to register with bus_type 'vio' because the bus was not initialized.
Driver 'tpm_ibmvtpm' was unable to register with bus_type 'vio' because the bus was not initialized.
This happens because those drivers are built-in, and are calling
vio_register_driver(). It in turn calls driver_register() with a
reference to vio_bus_type, but we haven't registered vio_bus_type with
the driver core.
Fix it by also guarding vio_register_driver() with a check to see if
we are on pseries.
Fixes: 4336b9337824 ("powerpc/pseries: Make vio and ibmebus initcalls pseries specific")
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Link: https://lore.kernel.org/r/20210316010938.525657-1-mpe@ellerman.id.au
One of the reasons that dlpar_cpu_offline can fail is when attempting to
offline the last online CPU of the kernel. This can be observed in a
pseries QEMU guest that has hotplugged CPUs. If the user offlines all
other CPUs of the guest, and a hotplugged CPU is now the last online
CPU, trying to reclaim it will fail.
The current error message in this situation returns rc with -EBUSY and a
generic explanation, e.g.:
pseries-hotplug-cpu: Failed to offline CPU PowerPC,POWER9, rc: -16
EBUSY can be caused by other conditions, such as cpu_hotplug_disable
being true. Throwing a more specific error message for this case,
instead of just "Failed to offline CPU", makes it clearer that the error
is in fact a known error situation instead of other generic/unknown
cause.
This patch adds a 'last online' check in dlpar_cpu_offline() to catch
the 'last online CPU' offline error, eturning a more informative error
message:
pseries-hotplug-cpu: Unable to remove last online CPU PowerPC,POWER9
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210323205056.52768-2-danielhb413@gmail.com
Commit 92c8c16f3457 ("powerpc/embedded6xx: Remove C2K board support")
moved the last selector of CONFIG_MV64X60.
As it is not a user selectable config, it can be removed.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/19e57d16692dcd1ca67ba880d7273a57fab416aa.1616085654.git.christophe.leroy@csgroup.eu
With below two commits:
commit c91435d95c49 ("powerpc/book3s64/hash/kuep: Enable KUEP on hash")
commit b2ff33a10c8b ("powerpc/book3s64/hash/kuap: Enable kuap on hash")
the kernel now supports kuap/kuep with hash translation. Hence select the
Kconfig even when radix is disabled.
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/20210318034829.72255-1-aneesh.kumar@linux.ibm.com
This is helpful to read the security flavor from inside the LPAR.
In /sys/kernel/debug/powerpc/security_features it can be seen if
mitigations are on or off but not the level set through the ASMI menu.
Furthermore, reporting it through /proc/powerpc/lparcfg allows an easy
processing by the lparstat command [1].
Export it like this in /proc/powerpc/lparcfg:
$ grep security_flavor /proc/powerpc/lparcfg
security_flavor=1
Value follows what is documented on the IBM support page [2]:
0 Speculative execution fully enabled
1 Speculative execution controls to mitigate user-to-kernel attacks
2 Speculative execution controls to mitigate user-to-kernel and
user-to-user side-channel attacks
[1] https://groups.google.com/g/powerpc-utils-devel/c/NaKXvdyl_UI/m/wa2stpIDAQAJ
[2] https://www.ibm.com/support/pages/node/715841
Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210305125554.5165-1-ldufour@linux.ibm.com
H_PROTECT expects the flag value to include flags:
AVPN, pp0, pp1, pp2, key0-key4, Noexec, CMO Option flags
This patch updates hpte_updatepp() to fetch the storage key value from
the linux page table and use the same in H_PROTECT hcall.
native_hpte_updatepp() is not updated because the kernel doesn't clear
the existing storage key value there. The kernel also doesn't use
hpte_updatepp() callback for updating storage keys.
This fixes the below kernel crash observed with KUAP enabled.
BUG: Unable to handle kernel data access on write at 0xc009fffffc440000
Faulting instruction address: 0xc0000000000b7030
Key fault AMR: 0xfcffffffffffffff IAMR: 0xc0000077bc498100
Found HPTE: v = 0x40070adbb6fffc05 r = 0x1ffffffffff1194
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
...
CFAR: c000000000010100 DAR: c009fffffc440000 DSISR: 02200000 IRQMASK: 0
...
NIP memset+0x68/0x104
LR pcpu_alloc+0x54c/0xb50
Call Trace:
pcpu_alloc+0x55c/0xb50 (unreliable)
blk_stat_alloc_callback+0x94/0x150
blk_mq_init_allocated_queue+0x64/0x560
blk_mq_init_queue+0x54/0xb0
scsi_mq_alloc_queue+0x30/0xa0
scsi_alloc_sdev+0x1cc/0x300
scsi_probe_and_add_lun+0xb50/0x1020
__scsi_scan_target+0x17c/0x790
scsi_scan_channel+0x90/0xe0
scsi_scan_host_selected+0x148/0x1f0
do_scan_async+0x2c/0x2a0
async_run_entry_fn+0x78/0x220
process_one_work+0x264/0x540
worker_thread+0xa8/0x600
kthread+0x190/0x1a0
ret_from_kernel_thread+0x5c/0x6c
With KUAP enabled the kernel uses storage key 3 for all its
translations. But as shown by the debug print, in this specific case we
have the hash page table entry created with key value 0.
Found HPTE: v = 0x40070adbb6fffc05 r = 0x1ffffffffff1194
and DSISR indicates a key fault.
This can happen due to parallel fault on the same EA by different CPUs:
CPU 0 CPU 1
fault on X
H_PAGE_BUSY set
fault on X
finish fault handling and
clear H_PAGE_BUSY
check for H_PAGE_BUSY
continue with fault handling.
This implies CPU1 will end up calling hpte_updatepp for address X and
the kernel updated the hash pte entry with key 0
Fixes: d94b827e89dc ("powerpc/book3s64/kuap: Use Key 3 for kernel mapping with hash translation")
Reported-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Debugged-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210326070755.304625-1-aneesh.kumar@linux.ibm.com
Fixes the following W=1 kernel build warning(s):
drivers/tty/hvc/hvc_vio.c:385:13: warning: no previous prototype for ‘hvc_vio_init_early’
385 | void __init hvc_vio_init_early(void)
| ^~~~~~~~~~~~~~~~~~
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210303124603.3150175-1-lee.jones@linaro.org
Commit 407d418f2fd4c20a ("powerpc/chrp: Move PHB discovery") moved the
sole call to hydra_init() to the source file where it is defined, so it
can be made static.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210223095345.2139416-1-geert@linux-m68k.org
The pseries join/suspend sequence in its current form was written with
the assumption that it was the only user of H_PROD and that it needn't
handle spurious successful returns from H_JOIN. That's wrong;
powerpc's paravirt spinlock code uses H_PROD, and CPUs entering
do_join() can be woken prematurely from H_JOIN with a status of
H_SUCCESS as a result. This causes all CPUs to exit the sequence
early, preventing suspend from occurring at all.
Add a 'done' boolean flag to the pseries_suspend_info struct, and have
the waking thread set it before waking the other threads. Threads
which receive H_SUCCESS from H_JOIN retry if the 'done' flag is still
unset.
Fixes: 9327dc0aeef3 ("powerpc/pseries/mobility: use stop_machine for join/suspend")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210315080045.460331-3-nathanl@linux.ibm.com
The atomic_t counter is the only shared state for the join/suspend
sequence so far, but that will change. Contain it in a
struct (pseries_suspend_info), and document its intended use. No
functional change.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210315080045.460331-2-nathanl@linux.ibm.com
Use the local variable that is passed to swiotlb_init_with_tbl for
freeing the memory in the failure case to isolate the code a little
better from swiotlb internals.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
clearing everything *except* S_ISGID (including the S_IFDIR, among
other things) is wrong. Just use init_inode_owner() and be done
with that...
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
have dump_skip() just remember how much needs to be skipped,
leave actual seeks/writing zeroes to the next dump_emit()
or the end of coredump output, whichever comes first.
And instead of playing with do_truncate() in the end, just
write one NUL at the end of the last gap (if any).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The driver core ignores the return value of struct bus_type::remove()
because there is only little that can be done. To simplify the quest to
make this function return void, let struct vio_driver::remove() return
void, too. All users already unconditionally return 0, this commit makes
it obvious that returning an error code is a bad idea.
Note there are two nominally different implementations for a vio bus:
one in arch/sparc/kernel/vio.c and the other in
arch/powerpc/platforms/pseries/vio.c. This patch only adapts the powerpc
one.
Before this patch for a device that was bound to a driver without a
remove callback vio_cmo_bus_remove(viodev) wasn't called. As the device
core still considers the device unbound after vio_bus_remove() returns
calling this unconditionally is the consistent behaviour which is
implemented here.
Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Acked-by: Lijun Pan <ljp@linux.ibm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[mpe: Drop unneeded hvcs_remove() forward declaration, squash in
change from sfr to drop ibmvnic_remove() forward declaration]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210225221834.160083-1-uwe@kleine-koenig.org
Depending on the number of online CPUs in the original kernel, it is
likely for CPU #0 to be offline in a kdump kernel. The associated IRQs
in the affinity mappings provided by irq_create_affinity_masks() are
thus not started by irq_startup(), as per-design with managed IRQs.
This can be a problem with multi-queue block devices driven by blk-mq :
such a non-started IRQ is very likely paired with the single queue
enforced by blk-mq during kdump (see blk_mq_alloc_tag_set()). This
causes the device to remain silent and likely hangs the guest at
some point.
This is a regression caused by commit 9ea69a55b3b9 ("powerpc/pseries:
Pass MSI affinity to irq_create_mapping()"). Note that this only happens
with the XIVE interrupt controller because XICS has a workaround to bypass
affinity, which is activated during kdump with the "noirqdistrib" kernel
parameter.
The issue comes from a combination of factors:
- discrepancy between the number of queues detected by the multi-queue
block driver, that was used to create the MSI vectors, and the single
queue mode enforced later on by blk-mq because of kdump (i.e. keeping
all queues fixes the issue)
- CPU#0 offline (i.e. kdump always succeed with CPU#0)
Given that I couldn't reproduce on x86, which seems to always have CPU#0
online even during kdump, I'm not sure where this should be fixed. Hence
going for another approach : fine-grained affinity is for performance
and we don't really care about that during kdump. Simply revert to the
previous working behavior of ignoring affinity masks in this case only.
Fixes: 9ea69a55b3b9 ("powerpc/pseries: Pass MSI affinity to irq_create_mapping()")
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210215094506.1196119-1-groug@kaod.org
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Merge tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull idmapped mounts from Christian Brauner:
"This introduces idmapped mounts which has been in the making for some
time. Simply put, different mounts can expose the same file or
directory with different ownership. This initial implementation comes
with ports for fat, ext4 and with Christoph's port for xfs with more
filesystems being actively worked on by independent people and
maintainers.
Idmapping mounts handle a wide range of long standing use-cases. Here
are just a few:
- Idmapped mounts make it possible to easily share files between
multiple users or multiple machines especially in complex
scenarios. For example, idmapped mounts will be used in the
implementation of portable home directories in
systemd-homed.service(8) where they allow users to move their home
directory to an external storage device and use it on multiple
computers where they are assigned different uids and gids. This
effectively makes it possible to assign random uids and gids at
login time.
- It is possible to share files from the host with unprivileged
containers without having to change ownership permanently through
chown(2).
- It is possible to idmap a container's rootfs and without having to
mangle every file. For example, Chromebooks use it to share the
user's Download folder with their unprivileged containers in their
Linux subsystem.
- It is possible to share files between containers with
non-overlapping idmappings.
- Filesystem that lack a proper concept of ownership such as fat can
use idmapped mounts to implement discretionary access (DAC)
permission checking.
- They allow users to efficiently changing ownership on a per-mount
basis without having to (recursively) chown(2) all files. In
contrast to chown (2) changing ownership of large sets of files is
instantenous with idmapped mounts. This is especially useful when
ownership of a whole root filesystem of a virtual machine or
container is changed. With idmapped mounts a single syscall
mount_setattr syscall will be sufficient to change the ownership of
all files.
- Idmapped mounts always take the current ownership into account as
idmappings specify what a given uid or gid is supposed to be mapped
to. This contrasts with the chown(2) syscall which cannot by itself
take the current ownership of the files it changes into account. It
simply changes the ownership to the specified uid and gid. This is
especially problematic when recursively chown(2)ing a large set of
files which is commong with the aforementioned portable home
directory and container and vm scenario.
- Idmapped mounts allow to change ownership locally, restricting it
to specific mounts, and temporarily as the ownership changes only
apply as long as the mount exists.
Several userspace projects have either already put up patches and
pull-requests for this feature or will do so should you decide to pull
this:
- systemd: In a wide variety of scenarios but especially right away
in their implementation of portable home directories.
https://systemd.io/HOME_DIRECTORY/
- container runtimes: containerd, runC, LXD:To share data between
host and unprivileged containers, unprivileged and privileged
containers, etc. The pull request for idmapped mounts support in
containerd, the default Kubernetes runtime is already up for quite
a while now: https://github.com/containerd/containerd/pull/4734
- The virtio-fs developers and several users have expressed interest
in using this feature with virtual machines once virtio-fs is
ported.
- ChromeOS: Sharing host-directories with unprivileged containers.
I've tightly synced with all those projects and all of those listed
here have also expressed their need/desire for this feature on the
mailing list. For more info on how people use this there's a bunch of
talks about this too. Here's just two recent ones:
https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdfhttps://fosdem.org/2021/schedule/event/containers_idmap/
This comes with an extensive xfstests suite covering both ext4 and
xfs:
https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts
It covers truncation, creation, opening, xattrs, vfscaps, setid
execution, setgid inheritance and more both with idmapped and
non-idmapped mounts. It already helped to discover an unrelated xfs
setgid inheritance bug which has since been fixed in mainline. It will
be sent for inclusion with the xfstests project should you decide to
merge this.
In order to support per-mount idmappings vfsmounts are marked with
user namespaces. The idmapping of the user namespace will be used to
map the ids of vfs objects when they are accessed through that mount.
By default all vfsmounts are marked with the initial user namespace.
The initial user namespace is used to indicate that a mount is not
idmapped. All operations behave as before and this is verified in the
testsuite.
Based on prior discussions we want to attach the whole user namespace
and not just a dedicated idmapping struct. This allows us to reuse all
the helpers that already exist for dealing with idmappings instead of
introducing a whole new range of helpers. In addition, if we decide in
the future that we are confident enough to enable unprivileged users
to setup idmapped mounts the permission checking can take into account
whether the caller is privileged in the user namespace the mount is
currently marked with.
The user namespace the mount will be marked with can be specified by
passing a file descriptor refering to the user namespace as an
argument to the new mount_setattr() syscall together with the new
MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
of extensibility.
The following conditions must be met in order to create an idmapped
mount:
- The caller must currently have the CAP_SYS_ADMIN capability in the
user namespace the underlying filesystem has been mounted in.
- The underlying filesystem must support idmapped mounts.
- The mount must not already be idmapped. This also implies that the
idmapping of a mount cannot be altered once it has been idmapped.
- The mount must be a detached/anonymous mount, i.e. it must have
been created by calling open_tree() with the OPEN_TREE_CLONE flag
and it must not already have been visible in the filesystem.
The last two points guarantee easier semantics for userspace and the
kernel and make the implementation significantly simpler.
By default vfsmounts are marked with the initial user namespace and no
behavioral or performance changes are observed.
The manpage with a detailed description can be found here:
1d7b902e28
In order to support idmapped mounts, filesystems need to be changed
and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
patches to convert individual filesystem are not very large or
complicated overall as can be seen from the included fat, ext4, and
xfs ports. Patches for other filesystems are actively worked on and
will be sent out separately. The xfstestsuite can be used to verify
that port has been done correctly.
The mount_setattr() syscall is motivated independent of the idmapped
mounts patches and it's been around since July 2019. One of the most
valuable features of the new mount api is the ability to perform
mounts based on file descriptors only.
Together with the lookup restrictions available in the openat2()
RESOLVE_* flag namespace which we added in v5.6 this is the first time
we are close to hardened and race-free (e.g. symlinks) mounting and
path resolution.
While userspace has started porting to the new mount api to mount
proper filesystems and create new bind-mounts it is currently not
possible to change mount options of an already existing bind mount in
the new mount api since the mount_setattr() syscall is missing.
With the addition of the mount_setattr() syscall we remove this last
restriction and userspace can now fully port to the new mount api,
covering every use-case the old mount api could. We also add the
crucial ability to recursively change mount options for a whole mount
tree, both removing and adding mount options at the same time. This
syscall has been requested multiple times by various people and
projects.
There is a simple tool available at
https://github.com/brauner/mount-idmapped
that allows to create idmapped mounts so people can play with this
patch series. I'll add support for the regular mount binary should you
decide to pull this in the following weeks:
Here's an example to a simple idmapped mount of another user's home
directory:
u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt
u1001@f2-vm:/$ ls -al /home/ubuntu/
total 28
drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
drwxr-xr-x 4 root root 4096 Oct 28 04:00 ..
-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile
-rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ ls -al /mnt/
total 28
drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 .
drwxr-xr-x 29 root root 4096 Oct 28 22:01 ..
-rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile
-rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ touch /mnt/my-file
u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file
u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file
u1001@f2-vm:/$ ls -al /mnt/my-file
-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file
u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file
u1001@f2-vm:/$ getfacl /mnt/my-file
getfacl: Removing leading '/' from absolute path names
# file: mnt/my-file
# owner: u1001
# group: u1001
user::rw-
user:u1001:rwx
group::rw-
mask::rwx
other::r--
u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
getfacl: Removing leading '/' from absolute path names
# file: home/ubuntu/my-file
# owner: ubuntu
# group: ubuntu
user::rw-
user:ubuntu:rwx
group::rw-
mask::rwx
other::r--"
* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
xfs: support idmapped mounts
ext4: support idmapped mounts
fat: handle idmapped mounts
tests: add mount_setattr() selftests
fs: introduce MOUNT_ATTR_IDMAP
fs: add mount_setattr()
fs: add attr_flags_to_mnt_flags helper
fs: split out functions to hold writers
namespace: only take read lock in do_reconfigure_mnt()
mount: make {lock,unlock}_mount_hash() static
namespace: take lock_mount_hash() directly when changing flags
nfs: do not export idmapped mounts
overlayfs: do not mount on top of idmapped mounts
ecryptfs: do not mount on top of idmapped mounts
ima: handle idmapped mounts
apparmor: handle idmapped mounts
fs: make helpers idmap mount aware
exec: handle idmapped mounts
would_dump: handle idmapped mounts
...
