This patch tries to fix the following BUG report:
[ 0.012313] BUG: MAX_STACK_TRACE_ENTRIES too low!
[ 0.012318] turning off the locking correctness validator.
[ 0.012321] Call Trace:
[ 0.012330] [c00000017666f6d0] [c000000000012128] .show_stack+0x78/0x184
(unreliable)
[ 0.012339] [c00000017666f780] [c0000000000b6348] .save_trace+0x12c/0x14c
[ 0.012345] [c00000017666f800] [c0000000000b7448] .mark_lock+0x2bc/0x710
[ 0.012351] [c00000017666f8b0] [c0000000000bb198] .__lock_acquire+0x748/0xaec
[ 0.012357] [c00000017666f9b0] [c0000000000bb684] .lock_acquire+0x148/0x194
[ 0.012365] [c00000017666fa80] [c00000000069371c]
.mutex_lock_nested+0x84/0x4ec
[ 0.012372] [c00000017666fb90] [c000000000096998]
.smpboot_register_percpu_thread+0x3c/0x10c
[ 0.012380] [c00000017666fc30] [c0000000009ba910] .spawn_ksoftirqd+0x28/0x48
[ 0.012386] [c00000017666fcb0] [c00000000000a98c] .do_one_initcall+0xd8/0x1d0
[ 0.012392] [c00000017666fd60] [c00000000000b1f8] .kernel_init+0x120/0x398
[ 0.012398] [c00000017666fe30] [c000000000009ad4]
.ret_from_kernel_thread+0x5c/0x64
[ 0.012404] [c00000017666fa00] [c00000017666fb20] 0xc00000017666fb20
[ 0.012410] [c00000017666fa80] [c00000000069371c]
.mutex_lock_nested+0x84/0x4ec
[ 0.012416] [c00000017666fb90] [c000000000096998]
.smpboot_register_percpu_thread+0x3c/0x10c
[ 0.012422] [c00000017666fc30] [c0000000009ba910] .spawn_ksoftirqd+0x28/0x48
[ 0.012427] [c00000017666fcb0] [c00000000000a98c] .do_one_initcall+0xd8/0x1d0
[ 0.012433] [c00000017666fd60] [c00000000000b1f8] .kernel_init+0x120/0x398
[ 0.012439] [c00000017666fe30] [c000000000009ad4]
.ret_from_kernel_thread+0x5c/0x64
.......
The reason is that the back chain of c00000017666fe30
(ret_from_kernel_thread) contains some invalid value, which might form a
loop.
Not very sure whether it is good to clear the back chain to 0 here.
Signed-off-by: Li Zhong <zh...@linux.vnet.ibm.com>
---
arch/powerpc/kernel/entry_64.S | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/arch/powerpc/kernel/entry_64.S
b/arch/powerpc/kernel/entry_64.S
index 56e0ff0..ad76666 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -374,6 +374,8 @@ _GLOBAL(ret_from_kernel_thread)
bl .schedule_tail
REST_NVGPRS(r1)
REST_GPR(2,r1)
+ li r3,0
+ std r3,0(r1)
mtlr r14
mr r3,r15
blrl
--
1.7.1
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
