diff options
| author | Hou Wenlong <houwenlong.hwl@antgroup.com> | 2023-06-09 17:45:31 +0800 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2023-11-13 12:23:27 +0100 |
| commit | 5c22c4726e4a9c6b2e182c0b21c2d3dd63f608c4 (patch) | |
| tree | 40ef340dd4cb669c419f31e696a5c9066218b3de /arch/x86/include/asm/paravirt.h | |
| parent | b85ea95d086471afb4ad062012a4d73cd328fa86 (diff) | |
x86/paravirt: Use relative reference for the original instruction offset
Similar to the alternative patching, use a relative reference for original
instruction offset rather than absolute one, which saves 8 bytes for one
PARA_SITE entry on x86_64. As a result, a R_X86_64_PC32 relocation is
generated instead of an R_X86_64_64 one, which also reduces relocation
metadata on relocatable builds. Hardcode the alignment to 4 now.
[ bp: Massage commit message. ]
Signed-off-by: Hou Wenlong <houwenlong.hwl@antgroup.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/9e6053107fbaabc0d33e5d2865c5af2c67ec9925.1686301237.git.houwenlong.hwl@antgroup.com
Diffstat (limited to 'arch/x86/include/asm/paravirt.h')
| -rw-r--r-- | arch/x86/include/asm/paravirt.h | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index 6c8ff12140ae..d9384e9d97f6 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -743,16 +743,16 @@ void native_pv_lock_init(void) __init; #else /* __ASSEMBLY__ */ -#define _PVSITE(ptype, ops, word, algn) \ +#define _PVSITE(ptype, ops) \ 771:; \ ops; \ 772:; \ .pushsection .parainstructions,"a"; \ - .align algn; \ - word 771b; \ + .align 4; \ + .long 771b-.; \ .byte ptype; \ .byte 772b-771b; \ - _ASM_ALIGN; \ + .align 4; \ .popsection @@ -760,7 +760,7 @@ void native_pv_lock_init(void) __init; #ifdef CONFIG_PARAVIRT_XXL #define PARA_PATCH(off) ((off) / 8) -#define PARA_SITE(ptype, ops) _PVSITE(ptype, ops, .quad, 8) +#define PARA_SITE(ptype, ops) _PVSITE(ptype, ops) #define PARA_INDIRECT(addr) *addr(%rip) #ifdef CONFIG_DEBUG_ENTRY |