diff options
| author | Josh Poimboeuf <[email protected]> | 2018-02-20 20:42:14 -0600 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2018-02-21 16:54:07 +0100 |
| commit | 0ca7d5baa1787e5f2a7abd6bfca3303b1bbb48ac (patch) | |
| tree | 866043b4ad57ddfb6fe60eef21ea1b0381e9f36e | |
| parent | 9fbcc57aa16424ef84cb54e0d9db3221763de88a (diff) | |
x86/entry/64: Simplify ENCODE_FRAME_POINTER
On 64-bit, the stack pointer is always aligned on interrupt, so instead
of setting the LSB of the pt_regs address, we can just add 1 to it.
Suggested-by: Linus Torvalds <[email protected]>
Signed-off-by: Josh Poimboeuf <[email protected]>
Cc: Andrew Lutomirski <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Dominik Brodowski <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/20180221024214.lhl5jfgw33c4vz3m@treble
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | arch/x86/entry/calling.h | 7 |
1 files changed, 1 insertions, 6 deletions
diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h index 5d10b7a85cad..be63330c5511 100644 --- a/arch/x86/entry/calling.h +++ b/arch/x86/entry/calling.h @@ -181,12 +181,7 @@ For 32-bit we have the following conventions - kernel is built with */ .macro ENCODE_FRAME_POINTER ptregs_offset=0 #ifdef CONFIG_FRAME_POINTER - .if \ptregs_offset - leaq \ptregs_offset(%rsp), %rbp - .else - mov %rsp, %rbp - .endif - orq $0x1, %rbp + leaq 1+\ptregs_offset(%rsp), %rbp #endif .endm |