diff options
| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2016-12-13 21:25:35 -0600 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-12-14 08:48:05 +0100 |
| commit | ec2d86a9b646d93f1948569f368e2c6f5449e6c7 (patch) | |
| tree | ce13273c0fac628752f83f8e46137a2839b150e1 /arch/x86/kernel/head_64.S | |
| parent | 9d85eb9119f4eeeb48e87adfcd71f752655700e9 (diff) | |
x86/boot/64: Use 'push' instead of 'call' in start_cpu()
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 uses a call
instruction to do that, which is rather obtuse. Use a straightforward
push instead.
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/4d8a1952759721d42d1e62ba9e4a7e3ac5df8574.1481685203.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/head_64.S')
| -rw-r--r-- | arch/x86/kernel/head_64.S | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 90de28841242..1facaf4f2308 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -298,7 +298,7 @@ ENTRY(start_cpu) * REX.W + FF /5 JMP m16:64 Jump far, absolute indirect, * address given in m16:64. */ - call 1f # put return address on stack for unwinder + pushq $1f # put return address on stack for unwinder 1: xorq %rbp, %rbp # clear frame pointer movq initial_code(%rip), %rax pushq $__KERNEL_CS # set correct cs |