linux-kernel - [RFC][PATCH 12/22] x86,fpu: Remove .fixup usage

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Message-ID: <20211104165525.228321055@infradead.org>
Date:   Thu, 04 Nov 2021 17:47:41 +0100
From:   Peter Zijlstra <peterz@...radead.org>
To:     x86@...nel.org
Cc:     linux-kernel@...r.kernel.org, peterz@...radead.org,
        jpoimboe@...hat.com, mark.rutland@....com, dvyukov@...gle.com,
        seanjc@...gle.com, pbonzini@...hat.com, mbenes@...e.cz
Subject: [RFC][PATCH 12/22] x86,fpu: Remove .fixup usage

Employ EX_TYPE_NEG_REG to store '-1' into the %[err] register on
exception.

Signed-off-by: Peter Zijlstra (Intel) <peterz@...radead.org>
---
 arch/x86/kernel/fpu/legacy.h |    6 +-----
 arch/x86/kernel/fpu/xstate.h |    6 +-----
 2 files changed, 2 insertions(+), 10 deletions(-)

--- a/arch/x86/kernel/fpu/legacy.h
+++ b/arch/x86/kernel/fpu/legacy.h
@@ -35,11 +35,7 @@ static inline void ldmxcsr(u32 mxcsr)
 	int err;							\
 	asm volatile("1:" #insn "\n\t"					\
 		     "2:\n"						\
-		     ".section .fixup,\"ax\"\n"				\
-		     "3:  movl $-1,%[err]\n"				\
-		     "    jmp  2b\n"					\
-		     ".previous\n"					\
-		     _ASM_EXTABLE(1b, 3b)				\
+		     _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_NEG_REG, %[err]) \
 		     : [err] "=r" (err), output				\
 		     : "0"(0), input);					\
 	err;								\
--- a/arch/x86/kernel/fpu/xstate.h
+++ b/arch/x86/kernel/fpu/xstate.h
@@ -107,11 +107,7 @@ static inline u64 xfeatures_mask_indepen
 		     "\n"						\
 		     "xor %[err], %[err]\n"				\
 		     "3:\n"						\
-		     ".pushsection .fixup,\"ax\"\n"			\
-		     "4: movl $-2, %[err]\n"				\
-		     "jmp 3b\n"						\
-		     ".popsection\n"					\
-		     _ASM_EXTABLE(661b, 4b)				\
+		     _ASM_EXTABLE_TYPE_REG(661b, 3b, EX_TYPE_NEG_REG, %[err]) \
 		     : [err] "=r" (err)					\
 		     : "D" (st), "m" (*st), "a" (lmask), "d" (hmask)	\
 		     : "memory")