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Subject[PATCH] Fix out-by-one error in traps.c
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We don't care if ebp is on the stack, we care about ebp + 4.  Without
this, lguest (with CONFIG_DEBUG_LOCKDEP) can touch a page unmapped by
CONFIG_DEBUG_PAGEALLOC.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

diff -r b0b1ab8ecf48 arch/i386/kernel/traps.c
--- a/arch/i386/kernel/traps.c Fri Aug 31 03:25:06 2007 +1000
+++ b/arch/i386/kernel/traps.c Fri Aug 31 07:57:35 2007 +1000
@@ -100,7 +100,7 @@ print_context_stack(struct thread_info *tinfo,
unsigned long addr;

#ifdef CONFIG_FRAME_POINTER
- while (valid_stack_ptr(tinfo, (void *)ebp)) {
+ while (valid_stack_ptr(tinfo, (void *)ebp + 4)) {
unsigned long new_ebp;
addr = *(unsigned long *)(ebp + 4);
ops->address(data, addr);

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