linux-kernel - [PATCH] x86/cpu: Use XGETBV and XSETBV mnemonics in fpu/internal.h

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Date:   Tue,  7 Jul 2020 19:47:22 +0200
From:   Uros Bizjak <ubizjak@...il.com>
To:     x86@...nel.org, linux-kernel@...r.kernel.org
Cc:     Uros Bizjak <ubizjak@...il.com>
Subject: [PATCH] x86/cpu: Use XGETBV and XSETBV mnemonics in fpu/internal.h

Current minimum required version of binutils is 2.23,
which supports XGETBV and XSETBV instruction mnemonics.

Replace the byte-wise specification of XGETBV and
XSETBV with these proper mnemonics.

Signed-off-by: Uros Bizjak <ubizjak@...il.com>
---
 arch/x86/include/asm/fpu/internal.h | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h
index 845e7481ab77..fbc7a333b28e 100644
--- a/arch/x86/include/asm/fpu/internal.h
+++ b/arch/x86/include/asm/fpu/internal.h
@@ -636,9 +636,7 @@ static inline u64 xgetbv(u32 index)
 {
 	u32 eax, edx;
 
-	asm volatile(".byte 0x0f,0x01,0xd0" /* xgetbv */
-		     : "=a" (eax), "=d" (edx)
-		     : "c" (index));
+	asm volatile("xgetbv" : "=a" (eax), "=d" (edx) : "c" (index));
 	return eax + ((u64)edx << 32);
 }
 
@@ -647,8 +645,7 @@ static inline void xsetbv(u32 index, u64 value)
 	u32 eax = value;
 	u32 edx = value >> 32;
 
-	asm volatile(".byte 0x0f,0x01,0xd1" /* xsetbv */
-		     : : "a" (eax), "d" (edx), "c" (index));
+	asm volatile("xsetbv" :: "a" (eax), "d" (edx), "c" (index));
 }
 
 #endif /* _ASM_X86_FPU_INTERNAL_H */
-- 
2.26.2