| Message ID | 1367916281.3083.24.camel@ThinkPad-T5421 (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index e514de5..d22e73e 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -439,8 +439,6 @@ ret_from_fork: ret_from_kernel_thread: REST_NVGPRS(r1) bl schedule_tail - li r3,0 - stw r3,0(r1) mtlr r14 mr r3,r15 PPC440EP_ERR42 diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 3fe5259..48e8a86 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -376,8 +376,6 @@ _GLOBAL(ret_from_fork) _GLOBAL(ret_from_kernel_thread) bl .schedule_tail REST_NVGPRS(r1) - li r3,0 - std r3,0(r1) ld r14, 0(r14) mtlr r14 mr r3,r15 diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index ceb4e7b..80af366 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -971,6 +971,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, * do some house keeping and then return from the fork or clone * system call, using the stack frame created above. */ + ((unsigned long *)sp)[0] = 0; sp -= sizeof(struct pt_regs); kregs = (struct pt_regs *) sp; sp -= STACK_FRAME_OVERHEAD;
Saw this warning again, and this time from the ret_from_fork path. It seems we could clear the back chain earlier in copy_thread(), which could cover both path, and also fix potential lockdep usage in schedule_tail(), or exception occurred before we clear the back chain. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> --- arch/powerpc/kernel/entry_32.S | 2 -- arch/powerpc/kernel/entry_64.S | 2 -- arch/powerpc/kernel/process.c | 1 + 3 files changed, 1 insertion(+), 4 deletions(-)