[PATCH -next v5 7/8] arm64: add uaccess to machine check safe

[Tong Tiangen]

If user access fail due to hardware memory error, only the relevant
processes are affected, so killing the user process and isolate the
error page with hardware memory errors is a more reasonable choice
than kernel panic.

Signed-off-by: Tong Tiangen <tongtiangen at huawei.com>
---
 arch/arm64/lib/copy_from_user.S | 8 ++++----
 arch/arm64/lib/copy_to_user.S   | 8 ++++----
 arch/arm64/mm/extable.c         | 8 ++++----
 3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S
index 34e317907524..402dd48a4f93 100644
--- a/arch/arm64/lib/copy_from_user.S
+++ b/arch/arm64/lib/copy_from_user.S
@@ -25,7 +25,7 @@
 	.endm
 
 	.macro strb1 reg, ptr, val
-	strb \reg, [\ptr], \val
+	USER(9998f, strb \reg, [\ptr], \val)
 	.endm
 
 	.macro ldrh1 reg, ptr, val
@@ -33,7 +33,7 @@
 	.endm
 
 	.macro strh1 reg, ptr, val
-	strh \reg, [\ptr], \val
+	USER(9998f, strh \reg, [\ptr], \val)
 	.endm
 
 	.macro ldr1 reg, ptr, val
@@ -41,7 +41,7 @@
 	.endm
 
 	.macro str1 reg, ptr, val
-	str \reg, [\ptr], \val
+	USER(9998f, str \reg, [\ptr], \val)
 	.endm
 
 	.macro ldp1 reg1, reg2, ptr, val
@@ -49,7 +49,7 @@
 	.endm
 
 	.macro stp1 reg1, reg2, ptr, val
-	stp \reg1, \reg2, [\ptr], \val
+	USER(9998f, stp \reg1, \reg2, [\ptr], \val)
 	.endm
 
 end	.req	x5
diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S
index 802231772608..4134bdb3a8b0 100644
--- a/arch/arm64/lib/copy_to_user.S
+++ b/arch/arm64/lib/copy_to_user.S
@@ -20,7 +20,7 @@
  *	x0 - bytes not copied
  */
 	.macro ldrb1 reg, ptr, val
-	ldrb  \reg, [\ptr], \val
+	USER(9998f, ldrb  \reg, [\ptr], \val)
 	.endm
 
 	.macro strb1 reg, ptr, val
@@ -28,7 +28,7 @@
 	.endm
 
 	.macro ldrh1 reg, ptr, val
-	ldrh  \reg, [\ptr], \val
+	USER(9998f, ldrh  \reg, [\ptr], \val)
 	.endm
 
 	.macro strh1 reg, ptr, val
@@ -36,7 +36,7 @@
 	.endm
 
 	.macro ldr1 reg, ptr, val
-	ldr \reg, [\ptr], \val
+	USER(9998f, ldr \reg, [\ptr], \val)
 	.endm
 
 	.macro str1 reg, ptr, val
@@ -44,7 +44,7 @@
 	.endm
 
 	.macro ldp1 reg1, reg2, ptr, val
-	ldp \reg1, \reg2, [\ptr], \val
+	USER(9998f, ldp \reg1, \reg2, [\ptr], \val)
 	.endm
 
 	.macro stp1 reg1, reg2, ptr, val
diff --git a/arch/arm64/mm/extable.c b/arch/arm64/mm/extable.c
index c301dcf6335f..8ca8d9639f9f 100644
--- a/arch/arm64/mm/extable.c
+++ b/arch/arm64/mm/extable.c
@@ -86,10 +86,10 @@ bool fixup_exception_mc(struct pt_regs *regs)
 	if (!ex)
 		return false;
 
-	/*
-	 * This is not complete, More Machine check safe extable type can
-	 * be processed here.
-	 */
+	switch (ex->type) {
+	case EX_TYPE_UACCESS_ERR_ZERO:
+		return ex_handler_uaccess_err_zero(ex, regs);
+	}
 
 	return false;
 }
-- 
2.25.1