linux/arch
Alistair Popple 28a5933e8d powerpc/powernv/npu: Add lock to prevent race in concurrent context init/destroy
The pnv_npu2_init_context() and pnv_npu2_destroy_context() functions
are used to allocate/free contexts to allow address translation and
shootdown by the NPU on a particular GPU. Context initialisation is
implicitly safe as it is protected by the requirement mmap_sem be held
in write mode, however pnv_npu2_destroy_context() does not require
mmap_sem to be held and it is not safe to call with a concurrent
initialisation for a different GPU.

It was assumed the driver would ensure destruction was not called
concurrently with initialisation. However the driver may be simplified
by allowing concurrent initialisation and destruction for different
GPUs. As npu context creation/destruction is not a performance
critical path and the critical section is not large a single spinlock
is used for simplicity.

Fixes: 1ab66d1fba ("powerpc/powernv: Introduce address translation services for Nvlink2")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Reviewed-by: Mark Hairgrove <mhairgrove@nvidia.com>
Tested-by: Mark Hairgrove <mhairgrove@nvidia.com>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-24 09:46:56 +10:00
..
alpha mm: introduce MAP_FIXED_NOREPLACE 2018-04-11 10:28:38 -07:00
arc kbuild: mark $(targets) as .SECONDARY and remove .PRECIOUS markers 2018-04-07 19:04:02 +09:00
arm Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
arm64 arm64: signal: don't force known signals to SIGKILL 2018-04-18 15:13:27 +01:00
c6x c6x: pass endianness info to sparse 2018-04-10 09:58:58 -04:00
h8300 h8300: remove extraneous __BIG_ENDIAN definition 2018-03-22 17:07:01 -07:00
hexagon
ia64 pci-v4.17-changes 2018-04-06 18:31:06 -07:00
m68k Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2018-04-09 09:15:46 -07:00
microblaze Microblaze patches for 4.17-rc1 2018-04-12 10:18:02 -07:00
mips MIPS fixes for 4.17-rc2 2018-04-20 08:25:31 -07:00
nds32 page cache: use xa_lock 2018-04-11 10:28:39 -07:00
nios2 nios2 update for v4.17-rc1 2018-04-11 16:02:18 -07:00
openrisc OpenRISC updates for v4.17 2018-04-15 12:27:58 -07:00
parisc parisc: Fix missing binfmt_elf32.o build error 2018-04-14 11:17:59 +02:00
powerpc powerpc/powernv/npu: Add lock to prevent race in concurrent context init/destroy 2018-04-24 09:46:56 +10:00
riscv RISC-V changes for 4.17 2018-04-04 16:43:47 -07:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-04-20 09:15:14 -07:00
sh Merge branch 'akpm' (patches from Andrew) 2018-04-14 08:50:50 -07:00
sparc Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
um Merge git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2018-04-11 16:36:47 -07:00
unicore32 unicore32: turn flush_dcache_mmap_lock into a no-op 2018-04-11 10:28:39 -07:00
x86 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-22 11:40:52 -07:00
xtensa mm: introduce MAP_FIXED_NOREPLACE 2018-04-11 10:28:38 -07:00
.gitignore
Kconfig kbuild: remove incremental linking option 2018-03-26 02:01:19 +09:00