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From: James Hogan <james.hogan@imgtec.com>
Date: Wed, 31 May 2017 16:19:49 +0100
Subject: [PATCH] MIPS: Fix mips_atomic_set() with EVA
References: bnc#1060662
Patch-mainline: v4.12.4
Git-commit: 4915e1b043d6286928207b1f6968197b50407294

commit 4915e1b043d6286928207b1f6968197b50407294 upstream.

EVA linked loads (LLE) and conditional stores (SCE) should be used on
EVA kernels for the MIPS_ATOMIC_SET operation of the sysmips system
call, or else the atomic set will apply to the kernel view of the
virtual address space (potentially unmapped on EVA kernels) rather than
the user view (TLB mapped).

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16151/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 arch/mips/kernel/syscall.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c
index 95e1b300ac0d..8f53dfe57bb4 100644
--- a/arch/mips/kernel/syscall.c
+++ b/arch/mips/kernel/syscall.c
@@ -29,6 +29,7 @@
 #include <linux/sched/task_stack.h>
 
 #include <asm/asm.h>
+#include <asm/asm-eva.h>
 #include <asm/branch.h>
 #include <asm/cachectl.h>
 #include <asm/cacheflush.h>
@@ -131,9 +132,11 @@ static inline int mips_atomic_set(unsigned long addr, unsigned long new)
 		__asm__ __volatile__ (
 		"	.set	"MIPS_ISA_ARCH_LEVEL"			\n"
 		"	li	%[err], 0				\n"
-		"1:	ll	%[old], (%[addr])			\n"
+		"1:							\n"
+		user_ll("%[old]", "(%[addr])")
 		"	move	%[tmp], %[new]				\n"
-		"2:	sc	%[tmp], (%[addr])			\n"
+		"2:							\n"
+		user_sc("%[tmp]", "(%[addr])")
 		"	beqz	%[tmp], 4f				\n"
 		"3:							\n"
 		"	.insn						\n"
-- 
2.14.2