From 669f8a900198599d3c2e2e463bafe12d30d96507 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Thu, 15 Jan 2015 09:17:12 +0100 Subject: [PATCH] x86/smap: Use ALTERNATIVE macro ... and drop unfolded version. No need for ASM_NOP3 anymore either as the alternatives do the proper padding at build time and insert proper NOPs at boot time. There should be no apparent operational change from this patch. Signed-off-by: Borislav Petkov --- arch/x86/include/asm/smap.h | 30 +++++++++--------------------- 1 file changed, 9 insertions(+), 21 deletions(-) diff --git a/arch/x86/include/asm/smap.h b/arch/x86/include/asm/smap.h index c56cb4f..ba665eb 100644 --- a/arch/x86/include/asm/smap.h +++ b/arch/x86/include/asm/smap.h @@ -27,23 +27,11 @@ #ifdef CONFIG_X86_SMAP -#define ASM_CLAC \ - 661: ASM_NOP3 ; \ - .pushsection .altinstr_replacement, "ax" ; \ - 662: __ASM_CLAC ; \ - .popsection ; \ - .pushsection .altinstructions, "a" ; \ - altinstruction_entry 661b, 662b, X86_FEATURE_SMAP, 3, 3, 0 ; \ - .popsection - -#define ASM_STAC \ - 661: ASM_NOP3 ; \ - .pushsection .altinstr_replacement, "ax" ; \ - 662: __ASM_STAC ; \ - .popsection ; \ - .pushsection .altinstructions, "a" ; \ - altinstruction_entry 661b, 662b, X86_FEATURE_SMAP, 3, 3, 0 ; \ - .popsection +#define ASM_CLAC \ + ALTERNATIVE "", __stringify(__ASM_CLAC), X86_FEATURE_SMAP + +#define ASM_STAC \ + ALTERNATIVE "", __stringify(__ASM_STAC), X86_FEATURE_SMAP #else /* CONFIG_X86_SMAP */ @@ -61,20 +49,20 @@ static __always_inline void clac(void) { /* Note: a barrier is implicit in alternative() */ - alternative(ASM_NOP3, __stringify(__ASM_CLAC), X86_FEATURE_SMAP); + alternative("", __stringify(__ASM_CLAC), X86_FEATURE_SMAP); } static __always_inline void stac(void) { /* Note: a barrier is implicit in alternative() */ - alternative(ASM_NOP3, __stringify(__ASM_STAC), X86_FEATURE_SMAP); + alternative("", __stringify(__ASM_STAC), X86_FEATURE_SMAP); } /* These macros can be used in asm() statements */ #define ASM_CLAC \ - ALTERNATIVE(ASM_NOP3, __stringify(__ASM_CLAC), X86_FEATURE_SMAP) + ALTERNATIVE("", __stringify(__ASM_CLAC), X86_FEATURE_SMAP) #define ASM_STAC \ - ALTERNATIVE(ASM_NOP3, __stringify(__ASM_STAC), X86_FEATURE_SMAP) + ALTERNATIVE("", __stringify(__ASM_STAC), X86_FEATURE_SMAP) #else /* CONFIG_X86_SMAP */ -- 2.7.4