diff options
author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2021-11-18 12:39:53 +0300 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-11-24 13:00:51 +0300 |
commit | 5bb60ea611db1e04814426ed4bd1c95d1487678e (patch) | |
tree | 8a1bc89c719e21697f25570aae04bf9fc98c98c2 /arch | |
parent | cf0b0e3712f7af90006f8317ff27278094c2c128 (diff) | |
download | linux-5bb60ea611db1e04814426ed4bd1c95d1487678e.tar.xz |
powerpc/32: Fix hardlockup on vmap stack overflow
Since the commit c118c7303ad5 ("powerpc/32: Fix vmap stack - Do not
activate MMU before reading task struct") a vmap stack overflow
results in a hard lockup. This is because emergency_ctx is still
addressed with its virtual address allthough data MMU is not active
anymore at that time.
Fix it by using a physical address instead.
Fixes: c118c7303ad5 ("powerpc/32: Fix vmap stack - Do not activate MMU before reading task struct")
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ce30364fb7ccda489272af4a1612b6aa147e1d23.1637227521.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch')
-rw-r--r-- | arch/powerpc/kernel/head_32.h | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h index 6b1ec9e3541b..349c4a820231 100644 --- a/arch/powerpc/kernel/head_32.h +++ b/arch/powerpc/kernel/head_32.h @@ -202,11 +202,11 @@ vmap_stack_overflow: mfspr r1, SPRN_SPRG_THREAD lwz r1, TASK_CPU - THREAD(r1) slwi r1, r1, 3 - addis r1, r1, emergency_ctx@ha + addis r1, r1, emergency_ctx-PAGE_OFFSET@ha #else - lis r1, emergency_ctx@ha + lis r1, emergency_ctx-PAGE_OFFSET@ha #endif - lwz r1, emergency_ctx@l(r1) + lwz r1, emergency_ctx-PAGE_OFFSET@l(r1) addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE EXCEPTION_PROLOG_2 0 vmap_stack_overflow prepare_transfer_to_handler |