From 3387a535ce629906d849864ef6a3c3437a645cb5 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 21 Jan 2016 16:49:22 -0600 Subject: [PATCH] x86/asm: Create stack frames in rwsem functions 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 Reviewed-by: Borislav Petkov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Bernd Petrovitsch Cc: Borislav Petkov Cc: Brian Gerst Cc: Chris J Arges Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Jiri Slaby Cc: Linus Torvalds Cc: Michal Marek Cc: Namhyung Kim Cc: Pedro Alves Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/ad0932bbead975b15f9578e4f2cf2ee5961eb840.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/lib/rwsem.S | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/arch/x86/lib/rwsem.S b/arch/x86/lib/rwsem.S index 40027db99140..be110efa0096 100644 --- a/arch/x86/lib/rwsem.S +++ b/arch/x86/lib/rwsem.S @@ -15,6 +15,7 @@ #include #include +#include #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) -- 2.20.1