[PATCH] x86_64: Dump stack and prevent recursion on early fault
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/x86_64/kernel/head.S b/arch/x86_64/kernel/head.S
index b6d8725..9bd2e7a 100644
--- a/arch/x86_64/kernel/head.S
+++ b/arch/x86_64/kernel/head.S
@@ -200,14 +200,22 @@
.quad init_thread_union+THREAD_SIZE-8
ENTRY(early_idt_handler)
+ cmpl $2,early_recursion_flag(%rip)
+ jz 1f
+ incl early_recursion_flag(%rip)
xorl %eax,%eax
movq 8(%rsp),%rsi # get rip
movq (%rsp),%rdx
movq %cr2,%rcx
leaq early_idt_msg(%rip),%rdi
call early_printk
+ cmpl $2,early_recursion_flag(%rip)
+ jz 1f
+ call dump_stack
1: hlt
jmp 1b
+early_recursion_flag:
+ .long 0
early_idt_msg:
.asciz "PANIC: early exception rip %lx error %lx cr2 %lx\n"
