Commit-ID: 5e219b3c671b34b2d79468fe89c44c0460c0f02b Gitweb: http://git.kernel.org/tip/5e219b3c671b34b2d79468fe89c44c0460c0f02b Author: Jiri Olsa <[email protected]> AuthorDate: Wed, 1 May 2013 17:25:41 +0200 Committer: Ingo Molnar <[email protected]> CommitDate: Tue, 28 May 2013 08:46:50 +0200
x86/signals: Propagate RF EFLAGS bit through the signal restore call While porting Vince's perf overflow tests I found perf event breakpoint overflow does not work properly. I found the x86 RF EFLAG bit not being set when returning from debug exception after triggering signal handler. Which is exactly what you get when you set perf breakpoint overflow SIGIO handler. This patch and the next two patches fix the underlying bugs. This patch adds the RF EFLAGS bit to be restored on return from signal from the original register context before the signal was entered. This will prevent the RF flag to disappear when returning from exception due to the signal handler being executed. Signed-off-by: Jiri Olsa <[email protected]> Tested-by: Oleg Nesterov <[email protected]> Reviewed-by: Frederic Weisbecker <[email protected]> Originally-Reported-by: Vince Weaver <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Corey Ashford <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: Vince Weaver <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Signed-off-by: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/ia32/ia32_signal.c | 2 -- arch/x86/include/asm/sighandling.h | 4 ++-- arch/x86/kernel/signal.c | 6 ------ 3 files changed, 2 insertions(+), 10 deletions(-) diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index cf1a471..bccfca6 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -34,8 +34,6 @@ #include <asm/sys_ia32.h> #include <asm/smap.h> -#define FIX_EFLAGS __FIX_EFLAGS - int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from) { int err = 0; diff --git a/arch/x86/include/asm/sighandling.h b/arch/x86/include/asm/sighandling.h index beff97f..7a95816 100644 --- a/arch/x86/include/asm/sighandling.h +++ b/arch/x86/include/asm/sighandling.h @@ -7,10 +7,10 @@ #include <asm/processor-flags.h> -#define __FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_OF | \ +#define FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_OF | \ X86_EFLAGS_DF | X86_EFLAGS_TF | X86_EFLAGS_SF | \ X86_EFLAGS_ZF | X86_EFLAGS_AF | X86_EFLAGS_PF | \ - X86_EFLAGS_CF) + X86_EFLAGS_CF | X86_EFLAGS_RF) void signal_fault(struct pt_regs *regs, void __user *frame, char *where); diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 6956299..9df4c0b 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -43,12 +43,6 @@ #include <asm/sigframe.h> -#ifdef CONFIG_X86_32 -# define FIX_EFLAGS (__FIX_EFLAGS | X86_EFLAGS_RF) -#else -# define FIX_EFLAGS __FIX_EFLAGS -#endif - #define COPY(x) do { \ get_user_ex(regs->x, &sc->x); \ } while (0) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
