linux-kernel - [tip: x86/fpu] x86/fpu: Use EX_TYPE_FAULT_MCE

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Date:   Tue, 14 Sep 2021 19:19:32 -0000
From:   "tip-bot2 for Thomas Gleixner" <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     Thomas Gleixner <tglx@...utronix.de>, Borislav Petkov <bp@...e.de>,
        x86@...nel.org, linux-kernel@...r.kernel.org
Subject: [tip: x86/fpu] x86/fpu: Use EX_TYPE_FAULT_MCE_SAFE for exception fixups

The following commit has been merged into the x86/fpu branch of tip:

Commit-ID:     c6304556f3ae98c943bbb4042a30205c98e4f921
Gitweb:        https://git.kernel.org/tip/c6304556f3ae98c943bbb4042a30205c98e4f921
Author:        Thomas Gleixner <tglx@...utronix.de>
AuthorDate:    Wed, 08 Sep 2021 15:29:23 +02:00
Committer:     Borislav Petkov <bp@...e.de>
CommitterDate: Mon, 13 Sep 2021 18:15:30 +02:00

x86/fpu: Use EX_TYPE_FAULT_MCE_SAFE for exception fixups

The macros used for restoring FPU state from a user space buffer can handle
all exceptions including #MC. They need to return the trap number in the
error case as the code which invokes them needs to distinguish the cause of
the failure. It aborts the operation for anything except #PF.

Use the new EX_TYPE_FAULT_MCE_SAFE exception table fixup type to document
the nature of the fixup.

Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
Signed-off-by: Borislav Petkov <bp@...e.de>
Link: https://lkml.kernel.org/r/20210908132525.387464538@linutronix.de
---
 arch/x86/include/asm/fpu/internal.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h
index ce6fc4f..cb1ca60 100644
--- a/arch/x86/include/asm/fpu/internal.h
+++ b/arch/x86/include/asm/fpu/internal.h
@@ -102,7 +102,7 @@ extern void save_fpregs_to_fpstate(struct fpu *fpu);
 		     "3:  negl %%eax\n"					\
 		     "    jmp  2b\n"					\
 		     ".previous\n"					\
-		     _ASM_EXTABLE_FAULT(1b, 3b)				\
+		     _ASM_EXTABLE_TYPE(1b, 3b, EX_TYPE_FAULT_MCE_SAFE)	\
 		     : [err] "=a" (err), output				\
 		     : "0"(0), input);					\
 	err;								\
@@ -209,7 +209,7 @@ static inline void fxsave(struct fxregs_state *fx)
 		     "3: negl %%eax\n\t"				\
 		     "jmp 2b\n\t"					\
 		     ".popsection\n\t"					\
-		     _ASM_EXTABLE_FAULT(1b, 3b)				\
+		     _ASM_EXTABLE_TYPE(1b, 3b, EX_TYPE_FAULT_MCE_SAFE)	\
 		     : [err] "=a" (err)					\
 		     : "D" (st), "m" (*st), "a" (lmask), "d" (hmask)	\
 		     : "memory")