x86/asm: Create stack frames in rwsem functions

jpoimboe · Ingo Molnar · commit 3387a535ce62 · 2016-02-24T08:35:43.000+01:00
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>
diff --git a/arch/x86/lib/rwsem.S b/arch/x86/lib/rwsem.S
@@ -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)
@@ -84,40 +85,48 @@
 
 /* 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
 	save_common_regs
 	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)
