From: Jann Horn <jannh@google.com>
Date: Sat, 25 Apr 2020 10:03:04 +0000 (-0500)
Subject: x86/entry/64: Fix unwind hints in rewind_stack_do_exit()
X-Git-Tag: v5.15~3902^2~11
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f977df7b7ca45a4ac4b66d30a8931d0434c394b1;p=platform%2Fkernel%2Flinux-starfive.git

x86/entry/64: Fix unwind hints in rewind_stack_do_exit()

The LEAQ instruction in rewind_stack_do_exit() moves the stack pointer
directly below the pt_regs at the top of the task stack before calling
do_exit(). Tell the unwinder to expect pt_regs.

Fixes: 8c1f75587a18 ("x86/entry/64: Add unwind hint annotations")
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Jones <dsj@fb.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lore.kernel.org/r/68c33e17ae5963854916a46f522624f8e1d264f2.1587808742.git.jpoimboe@redhat.com
---

diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 34a5889..9fe0d5c 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1739,7 +1739,7 @@ SYM_CODE_START(rewind_stack_do_exit)
 
 	movq	PER_CPU_VAR(cpu_current_top_of_stack), %rax
 	leaq	-PTREGS_SIZE(%rax), %rsp
-	UNWIND_HINT_FUNC sp_offset=PTREGS_SIZE
+	UNWIND_HINT_REGS
 
 	call	do_exit
 SYM_CODE_END(rewind_stack_do_exit)