From a67798cd7bb130bf37f5ffb28f3260f4c10232db Mon Sep 17 00:00:00 2001 From: Martin Hicks Date: Fri, 30 Jan 2009 10:50:54 -0600 Subject: x86: push old stack address on irqstack for unwinder Impact: Fixes dumpstack and KDB on 64 bits This re-adds the old stack pointer to the top of the irqstack to help with unwinding. It was removed in commit d99015b1abbad743aa049b439c1e1dede6d0fa49 as part of the save_args out-of-line work. Both dumpstack and KDB require this information. Signed-off-by: Martin Hicks Signed-off-by: H. Peter Anvin --- arch/x86/kernel/entry_64.S | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86') diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index e28c7a98779..a1346217e43 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -346,6 +346,7 @@ ENTRY(save_args) popq_cfi %rax /* move return address... */ mov %gs:pda_irqstackptr,%rsp EMPTY_FRAME 0 + pushq_cfi %rbp /* backlink for unwinder */ pushq_cfi %rax /* ... to the new stack */ /* * We entered an interrupt context - irqs are off: -- cgit v1.2.3