diff options
| author | Andi Kleen <ak@suse.de> | 2006-08-02 22:37:28 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-08-02 20:19:54 -0700 |
| commit | 2699500b31f41fc25656c42548c8a388c8a329fe (patch) | |
| tree | 6f7ccd0318b9e53394cb276819f2d358ce933afa | |
| parent | ae74c3b69a08e1de20cb681ec959f3a48af0006a (diff) | |
[PATCH] x86_64: Fix backtracing for interrupt stacks
Re-add backlink for old style unwinder to stack switching. Add proper
stack frame and CFI annotations to call_softirq
This prevents a oops when backtracing with fallback through the
interrupt stack top.
Suggested by Jan Beulich and Herbert Xu wanted it in 2.6.18.
Cc: jbeulich@novell.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | arch/x86_64/kernel/entry.S | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index d464dded68c..6f810424df4 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -513,6 +513,7 @@ END(stub_rt_sigreturn) swapgs 1: incl %gs:pda_irqcount # RED-PEN should check preempt count cmoveq %gs:pda_irqstackptr,%rsp + push %rbp # backlink for old unwinder /* * We entered an interrupt context - irqs are off: */ @@ -1139,18 +1140,21 @@ ENTRY(machine_check) END(machine_check) #endif +/* Call softirq on interrupt stack. Interrupts are off. */ ENTRY(call_softirq) CFI_STARTPROC - movq %gs:pda_irqstackptr,%rax - movq %rsp,%rdx - CFI_DEF_CFA_REGISTER rdx + push %rbp + CFI_ADJUST_CFA_OFFSET 8 + CFI_REL_OFFSET rbp,0 + mov %rsp,%rbp + CFI_DEF_CFA_REGISTER rbp incl %gs:pda_irqcount - cmove %rax,%rsp - pushq %rdx - /*todo CFI_DEF_CFA_EXPRESSION ...*/ + cmove %gs:pda_irqstackptr,%rsp + push %rbp # backlink for old unwinder call __do_softirq - popq %rsp + leaveq CFI_DEF_CFA_REGISTER rsp + CFI_ADJUST_CFA_OFFSET -8 decl %gs:pda_irqcount ret CFI_ENDPROC |