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x86/asm: Create stack frames in rwsem functions

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rwsem.S has several callable non-leaf functions which don't honor
CONFIG_FRAME_POINTER, which can result in bad stack traces.

Create stack frames for them when CONFIG_FRAME_POINTER is enabled.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/ad0932bbead975b15f9578e4f2cf2ee5961eb840.1453405861.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Josh Poimboeuf 2016-01-21 16:49:22 -06:00 committed by Ingo Molnar
parent 1352330949
commit 3387a535ce
1 changed files with 10 additions and 1 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

11
arch/x86/lib/rwsem.S
View file

@ -15,6 +15,7 @@
#include <linux/linkage.h>
#include <asm/alternative-asm.h>
#include <asm/frame.h>
#define __ASM_HALF_REG(reg) __ASM_SEL(reg, e##reg)
#define __ASM_HALF_SIZE(inst) __ASM_SEL(inst##w, inst##l)
@ -84,24 +85,29 @@
/* Fix up special calling conventions */
ENTRY(call_rwsem_down_read_failed)
FRAME_BEGIN
save_common_regs
__ASM_SIZE(push,) %__ASM_REG(dx)
movq %rax,%rdi
call rwsem_down_read_failed
__ASM_SIZE(pop,) %__ASM_REG(dx)
restore_common_regs
FRAME_END
ret
ENDPROC(call_rwsem_down_read_failed)
ENTRY(call_rwsem_down_write_failed)
FRAME_BEGIN
save_common_regs
movq %rax,%rdi
call rwsem_down_write_failed
restore_common_regs
FRAME_END
ret
ENDPROC(call_rwsem_down_write_failed)
ENTRY(call_rwsem_wake)
FRAME_BEGIN
/* do nothing if still outstanding active readers */
__ASM_HALF_SIZE(dec) %__ASM_HALF_REG(dx)
jnz 1f
@ -109,15 +115,18 @@ ENTRY(call_rwsem_wake)
movq %rax,%rdi
call rwsem_wake
restore_common_regs
1: ret
1: FRAME_END
ret
ENDPROC(call_rwsem_wake)
ENTRY(call_rwsem_downgrade_wake)
FRAME_BEGIN
save_common_regs
__ASM_SIZE(push,) %__ASM_REG(dx)
movq %rax,%rdi
call rwsem_downgrade_wake
__ASM_SIZE(pop,) %__ASM_REG(dx)
restore_common_regs
FRAME_END
ret
ENDPROC(call_rwsem_downgrade_wake)