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

commit f977df7b7ca45a4ac4b66d30a8931d0434c394b1 upstream.

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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index cf6236ced5325417f05ed24cccaa371439a5ffe3..abf25a696c1c55301c14bb8bf31c14a82eaeaaa8 100644 (file)
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1740,7 +1740,7 @@ ENTRY(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
 END(rewind_stack_do_exit)