Messages in this thread Patch in this message | | | From | Josh Poimboeuf <> | Subject | [PATCH 2/2] x86/boot/64: push correct start_cpu() return address | Date | Tue, 13 Dec 2016 21:25:36 -0600 |
| |
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 <jpoimboe@redhat.com> --- 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" -- 2.7.4
| |