From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Wed, 28 Nov 2018 23:20:11 +0100
Subject: x86/fpu: Add might_fault() to user_insn()
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Git-commit: 6637401c35b2f327a35d27f44bda05e327f2f017
Patch-mainline: 5.0-rc1
References: git-fixes

Every user of user_insn() passes an user memory pointer to this macro.

Add might_fault() to user_insn() so we can spot users which are using
this macro in sections where page faulting is not allowed.

 [ bp: Space it out to make it more visible. ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Rik van Riel <riel@surriel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm ML <kvm@vger.kernel.org>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20181128222035.2996-6-bigeasy@linutronix.de
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 arch/x86/include/asm/fpu/internal.h |    3 +++
 1 file changed, 3 insertions(+)

--- a/arch/x86/include/asm/fpu/internal.h
+++ b/arch/x86/include/asm/fpu/internal.h
@@ -107,6 +107,9 @@ extern void fpstate_sanitize_xstate(stru
 #define user_insn(insn, output, input...)				\
 ({									\
 	int err;							\
+									\
+	might_fault();							\
+									\
 	asm volatile(ASM_STAC "\n"					\
 		     "1:" #insn "\n\t"					\
 		     "2: " ASM_CLAC "\n"				\