diff options
author | Josh Poimboeuf <[email protected]> | 2016-12-13 21:25:35 -0600 |
---|---|---|
committer | Ingo Molnar <[email protected]> | 2016-12-14 08:48:05 +0100 |
commit | ec2d86a9b646d93f1948569f368e2c6f5449e6c7 (patch) | |
tree | ce13273c0fac628752f83f8e46137a2839b150e1 | |
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 <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Cc: Andy Lutomirski <[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/4d8a1952759721d42d1e62ba9e4a7e3ac5df8574.1481685203.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <[email protected]>
-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 |