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| author | Michael Ellerman <mpe@ellerman.id.au> | 2017-04-06 15:34:38 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-04-07 13:12:58 +0200 |
| commit | 4749228f022893faf54a3dbc70796f78b7d4f342 (patch) | |
| tree | 5544229f8bebdef3d133417542fb846bd7256d46 /arch | |
| parent | powerpc/mm: Add missing global TLB invalidate if cxl is active (diff) | |
| download | linux-4749228f022893faf54a3dbc70796f78b7d4f342.tar.xz linux-4749228f022893faf54a3dbc70796f78b7d4f342.zip | |
powerpc/crypto/crc32c-vpmsum: Fix missing preempt_disable()
In crc32c_vpmsum() we call enable_kernel_altivec() without first
disabling preemption, which is not allowed:
WARNING: CPU: 9 PID: 2949 at ../arch/powerpc/kernel/process.c:277 enable_kernel_altivec+0x100/0x120
Modules linked in: dm_thin_pool dm_persistent_data dm_bio_prison dm_bufio libcrc32c vmx_crypto ...
CPU: 9 PID: 2949 Comm: docker Not tainted 4.11.0-rc5-compiler_gcc-6.3.1-00033-g308ac7563944 #381
...
NIP [c00000000001e320] enable_kernel_altivec+0x100/0x120
LR [d000000003df0910] crc32c_vpmsum+0x108/0x150 [crc32c_vpmsum]
Call Trace:
0xc138fd09 (unreliable)
crc32c_vpmsum+0x108/0x150 [crc32c_vpmsum]
crc32c_vpmsum_update+0x3c/0x60 [crc32c_vpmsum]
crypto_shash_update+0x88/0x1c0
crc32c+0x64/0x90 [libcrc32c]
dm_bm_checksum+0x48/0x80 [dm_persistent_data]
sb_check+0x84/0x120 [dm_thin_pool]
dm_bm_validate_buffer.isra.0+0xc0/0x1b0 [dm_persistent_data]
dm_bm_read_lock+0x80/0xf0 [dm_persistent_data]
__create_persistent_data_objects+0x16c/0x810 [dm_thin_pool]
dm_pool_metadata_open+0xb0/0x1a0 [dm_thin_pool]
pool_ctr+0x4cc/0xb60 [dm_thin_pool]
dm_table_add_target+0x16c/0x3c0
table_load+0x184/0x400
ctl_ioctl+0x2f0/0x560
dm_ctl_ioctl+0x38/0x50
do_vfs_ioctl+0xd8/0x920
SyS_ioctl+0x68/0xc0
system_call+0x38/0xfc
It used to be sufficient just to call pagefault_disable(), because that
also disabled preemption. But the two were decoupled in commit 8222dbe21e79
("sched/preempt, mm/fault: Decouple preemption from the page fault
logic") in mid 2015.
So add the missing preempt_disable/enable(). We should also call
disable_kernel_fp(), although it does nothing by default, there is a
debug switch to make it active and all enables should be paired with
disables.
Fixes: 6dd7a82cc54e ("crypto: powerpc - Add POWER8 optimised crc32c")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/crypto/crc32c-vpmsum_glue.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/powerpc/crypto/crc32c-vpmsum_glue.c b/arch/powerpc/crypto/crc32c-vpmsum_glue.c index 411994551afc..f058e0c3e4d4 100644 --- a/arch/powerpc/crypto/crc32c-vpmsum_glue.c +++ b/arch/powerpc/crypto/crc32c-vpmsum_glue.c @@ -33,10 +33,13 @@ static u32 crc32c_vpmsum(u32 crc, unsigned char const *p, size_t len) } if (len & ~VMX_ALIGN_MASK) { + preempt_disable(); pagefault_disable(); enable_kernel_altivec(); crc = __crc32c_vpmsum(crc, p, len & ~VMX_ALIGN_MASK); + disable_kernel_altivec(); pagefault_enable(); + preempt_enable(); } tail = len & VMX_ALIGN_MASK; |