Commit-ID: 31dcfec11f827e9a5d8720fe4728f1305894884f Gitweb: http://git.kernel.org/tip/31dcfec11f827e9a5d8720fe4728f1305894884f Author: Josh Poimboeuf <[email protected]> AuthorDate: Tue, 13 Dec 2016 21:25:36 -0600 Committer: Ingo Molnar <[email protected]> CommitDate: Wed, 14 Dec 2016 08:48:05 +0100
x86/boot/64: Push correct start_cpu() return address start_cpu() pushes a text address on the stack so that stack traces from idle tasks will show start_cpu() at the end. But it currently shows the wrong function offset. It's more correct to show the address immediately after the 'lretq' instruction. Signed-off-by: Josh Poimboeuf <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/2cadd9f16c77da7ee7957bfc5e1c67928c23ca48.1481685203.git.jpoim...@redhat.com Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/kernel/head_64.S | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 1facaf4..b467b14 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -298,12 +298,13 @@ ENTRY(start_cpu) * REX.W + FF /5 JMP m16:64 Jump far, absolute indirect, * address given in m16:64. */ - pushq $1f # put return address on stack for unwinder -1: xorq %rbp, %rbp # clear frame pointer + pushq $.Lafter_lret # put return address on stack for unwinder + xorq %rbp, %rbp # clear frame pointer movq initial_code(%rip), %rax pushq $__KERNEL_CS # set correct cs pushq %rax # target address in negative space lretq +.Lafter_lret: ENDPROC(start_cpu) #include "verify_cpu.S"
