From c05991ed12fd71e539dd8de8f5663450cd0c934c Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 30 Aug 2006 19:37:08 +0200 Subject: [PATCH] [PATCH] x86_64: Add kernel thread stack frame termination for properly stopping stack unwinds. One open question: Should these added pushes perhaps be made conditional upon CONFIG_STACK_UNWIND or CONFIG_UNWIND_INFO? [AK: Not needed -- these are all very slow paths] Signed-off-by: Jan Beulich Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- arch/x86_64/kernel/entry.S | 3 +++ arch/x86_64/kernel/head.S | 1 + 2 files changed, 4 insertions(+) diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index 6f810424df44..aa8d8939abc1 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -973,6 +973,8 @@ ENTRY(kernel_thread) ENDPROC(kernel_thread) child_rip: + pushq $0 # fake return address + CFI_STARTPROC /* * Here we are in the child and the registers are set as they were * at kernel_thread() invocation in the parent. @@ -983,6 +985,7 @@ child_rip: # exit xorl %edi, %edi call do_exit + CFI_ENDPROC ENDPROC(child_rip) /* diff --git a/arch/x86_64/kernel/head.S b/arch/x86_64/kernel/head.S index 6df05e6034fa..c9739ca81d06 100644 --- a/arch/x86_64/kernel/head.S +++ b/arch/x86_64/kernel/head.S @@ -191,6 +191,7 @@ startup_64: * jump */ movq initial_code(%rip),%rax + pushq $0 # fake return address jmp *%rax /* SMP bootup changes these two */ -- 2.20.1