renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-23 12:43:55 +08:00
Code

x86/entry/64: Simplify ENCODE_FRAME_POINTER

Browse Source 
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 <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180221024214.lhl5jfgw33c4vz3m@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Josh Poimboeuf 2018-02-20 20:42:14 -06:00 committed by Ingo Molnar
parent 9fbcc57aa1
commit 0ca7d5baa1
1 changed files with 1 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
arch/x86/entry/calling.h
View File

@ -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