| From 124482935fb7fb9303c8a8ab930149c6a93d9910 Mon Sep 17 00:00:00 2001 |
| From: Andi Kleen <andi@firstfloor.org> |
| Date: Fri, 18 Jun 2010 23:09:00 +0200 |
| Subject: x86: Fix vsyscall on gcc 4.5 with -Os |
| |
| From: Andi Kleen <andi@firstfloor.org> |
| |
| commit 124482935fb7fb9303c8a8ab930149c6a93d9910 upstream. |
| |
| This fixes the -Os breaks with gcc 4.5 bug. rdtsc_barrier needs to be |
| force inlined, otherwise user space will jump into kernel space and |
| kill init. |
| |
| This also addresses http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44129 |
| I believe. |
| |
| Signed-off-by: Andi Kleen <ak@linux.intel.com> |
| LKML-Reference: <20100618210859.GA10913@basil.fritz.box> |
| Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| arch/x86/include/asm/system.h | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/arch/x86/include/asm/system.h |
| +++ b/arch/x86/include/asm/system.h |
| @@ -451,7 +451,7 @@ void stop_this_cpu(void *dummy); |
| * |
| * (Could use an alternative three way for this if there was one.) |
| */ |
| -static inline void rdtsc_barrier(void) |
| +static __always_inline void rdtsc_barrier(void) |
| { |
| alternative(ASM_NOP3, "mfence", X86_FEATURE_MFENCE_RDTSC); |
| alternative(ASM_NOP3, "lfence", X86_FEATURE_LFENCE_RDTSC); |
