diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/include/asm/nospec-branch.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index 10731ccfed37..c936ce9f0c47 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -50,6 +50,7 @@ * the optimal version - two calls, each with their own speculation * trap should their return address end up getting used, in a loop. */ +#ifdef CONFIG_X86_64 #define __FILL_RETURN_BUFFER(reg, nr) \ mov $(nr/2), reg; \ 771: \ @@ -60,6 +61,17 @@ jnz 771b; \ /* barrier for jnz misprediction */ \ lfence; +#else +/* + * i386 doesn't unconditionally have LFENCE, as such it can't + * do a loop. + */ +#define __FILL_RETURN_BUFFER(reg, nr) \ + .rept nr; \ + __FILL_RETURN_SLOT; \ + .endr; \ + add $(BITS_PER_LONG/8) * nr, %_ASM_SP; +#endif /* * Stuff a single RSB slot. |