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| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2016-01-21 16:49:32 -0600 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-02-24 08:35:44 +0100 |
| commit | 16df4ff8604881db0130f93f4b6ade759fa48e87 (patch) | |
| tree | c422a1ea1fd661fc017c5f25fcd21af7020ba5b8 | |
| parent | 5c1d5f283a855a5fe6b4f122054d85072b97ae4a (diff) | |
| download | lwn-16df4ff8604881db0130f93f4b6ade759fa48e87.tar.gz lwn-16df4ff8604881db0130f93f4b6ade759fa48e87.zip | |
x86/locking: Create stack frame in PV unlock
The assembly PV_UNLOCK function is a callable non-leaf function which
doesn't honor CONFIG_FRAME_POINTER, which can result in bad stack
traces.
Create a stack frame when CONFIG_FRAME_POINTER is enabled.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
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: Waiman Long <Waiman.Long@hpe.com>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/6685a72ddbbd0ad3694337cca0af4b4ea09f5f40.1453405861.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | arch/x86/include/asm/qspinlock_paravirt.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/include/asm/qspinlock_paravirt.h b/arch/x86/include/asm/qspinlock_paravirt.h index 9f92c180ed2f..9d55f9b6e167 100644 --- a/arch/x86/include/asm/qspinlock_paravirt.h +++ b/arch/x86/include/asm/qspinlock_paravirt.h @@ -36,8 +36,10 @@ PV_CALLEE_SAVE_REGS_THUNK(__pv_queued_spin_unlock_slowpath); */ asm (".pushsection .text;" ".globl " PV_UNLOCK ";" + ".type " PV_UNLOCK ", @function;" ".align 4,0x90;" PV_UNLOCK ": " + FRAME_BEGIN "push %rdx;" "mov $0x1,%eax;" "xor %edx,%edx;" @@ -45,6 +47,7 @@ asm (".pushsection .text;" "cmp $0x1,%al;" "jne .slowpath;" "pop %rdx;" + FRAME_END "ret;" ".slowpath: " "push %rsi;" @@ -52,6 +55,7 @@ asm (".pushsection .text;" "call " PV_UNLOCK_SLOWPATH ";" "pop %rsi;" "pop %rdx;" + FRAME_END "ret;" ".size " PV_UNLOCK ", .-" PV_UNLOCK ";" ".popsection"); |