Use MOVL when reading segment registers to avoid 0x66 operand-size override insn prefix. The segment value is always 16-bit and gets zero-extended to the full 32-bit size.
Signed-off-by: Uros Bizjak <[email protected]> Tested-by: Michael Kelley <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: "H. Peter Anvin" <[email protected]> --- arch/x86/include/asm/segment.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h index f59ae7186940..9f5be2bbd291 100644 --- a/arch/x86/include/asm/segment.h +++ b/arch/x86/include/asm/segment.h @@ -348,7 +348,7 @@ static inline void __loadsegment_fs(unsigned short value) * Save a segment register away: */ #define savesegment(seg, value) \ - asm("mov %%" #seg ",%0":"=r" (value) : : "memory") + asm("movl %%" #seg ",%k0" : "=r" (value) : : "memory") #endif /* !__ASSEMBLER__ */ #endif /* __KERNEL__ */ -- 2.52.0
