metag/usercopy: Add missing fixups

[ Upstream commit b884a190 ]

The rapf copy loops in the Meta usercopy code is missing some extable
entries for HTP cores with unaligned access checking enabled, where
faults occur on the instruction immediately after the faulting access.

Add the fixup labels and extable entries for these cases so that corner
case user copy failures don't cause kernel crashes.

Fixes: 373cd784 ("metag: Memory handling")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>

arch/metag/lib/usercopy.c

@@ -259,27 +259,31 @@
 		"MGETL	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
 		"22:\n"							\
 		"MSETL	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
-		"SUB	%3, %3, #32\n"					\
 		"23:\n"							\
-		"MGETL	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
+		"SUB	%3, %3, #32\n"					\
 		"24:\n"							\
+		"MGETL	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
+		"25:\n"							\
 		"MSETL	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
+		"26:\n"							\
 		"SUB	%3, %3, #32\n"					\
 		"DCACHE	[%1+#-64], D0Ar6\n"				\
 		"BR	$Lloop"id"\n"					\
 									\
 		"MOV	RAPF, %1\n"					\
-		"25:\n"							\
+		"27:\n"							\
 		"MGETL	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
-		"26:\n"							\
+		"28:\n"							\
 		"MSETL	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
+		"29:\n"							\
 		"SUB	%3, %3, #32\n"					\
-		"27:\n"							\
+		"30:\n"							\
 		"MGETL	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
-		"28:\n"							\
+		"31:\n"							\
 		"MSETL	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
+		"32:\n"							\
 		"SUB	%0, %0, #8\n"					\
-		"29:\n"							\
+		"33:\n"							\
 		"SETL	[%0++], D0.7, D1.7\n"				\
 		"SUB	%3, %3, #32\n"					\
 		"1:"							\
@@ -311,7 +315,11 @@
 		"	.long 26b,3b\n"					\
 		"	.long 27b,3b\n"					\
 		"	.long 28b,3b\n"					\
-		"	.long 29b,4b\n"					\
+		"	.long 29b,3b\n"					\
+		"	.long 30b,3b\n"					\
+		"	.long 31b,3b\n"					\
+		"	.long 32b,3b\n"					\
+		"	.long 33b,4b\n"					\
 		"	.previous\n"					\
 		: "=r" (to), "=r" (from), "=r" (ret), "=d" (n)		\
 		: "0" (to), "1" (from), "2" (ret), "3" (n)		\
@@ -402,47 +410,55 @@
 		"MGETD	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
 		"22:\n"							\
 		"MSETD	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
-		"SUB	%3, %3, #16\n"					\
 		"23:\n"							\
-		"MGETD	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
-		"24:\n"							\
-		"MSETD	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
 		"SUB	%3, %3, #16\n"					\
-		"25:\n"							\
+		"24:\n"							\
 		"MGETD	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
-		"26:\n"							\
+		"25:\n"							\
 		"MSETD	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
+		"26:\n"							\
 		"SUB	%3, %3, #16\n"					\
 		"27:\n"							\
 		"MGETD	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
 		"28:\n"							\
 		"MSETD	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
+		"29:\n"							\
+		"SUB	%3, %3, #16\n"					\
+		"30:\n"							\
+		"MGETD	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
+		"31:\n"							\
+		"MSETD	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
+		"32:\n"							\
 		"SUB	%3, %3, #16\n"					\
 		"DCACHE	[%1+#-64], D0Ar6\n"				\
 		"BR	$Lloop"id"\n"					\
 									\
 		"MOV	RAPF, %1\n"					\
-		"29:\n"							\
+		"33:\n"							\
 		"MGETD	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
-		"30:\n"							\
+		"34:\n"							\
 		"MSETD	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
+		"35:\n"							\
 		"SUB	%3, %3, #16\n"					\
-		"31:\n"							\
+		"36:\n"							\
 		"MGETD	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
-		"32:\n"							\
+		"37:\n"							\
 		"MSETD	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
+		"38:\n"							\
 		"SUB	%3, %3, #16\n"					\
-		"33:\n"							\
+		"39:\n"							\
 		"MGETD	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
-		"34:\n"							\
+		"40:\n"							\
 		"MSETD	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
+		"41:\n"							\
 		"SUB	%3, %3, #16\n"					\
-		"35:\n"							\
+		"42:\n"							\
 		"MGETD	D0FrT, D0.5, D0.6, D0.7, [%1++]\n"		\
-		"36:\n"							\
+		"43:\n"							\
 		"MSETD	[%0++], D0FrT, D0.5, D0.6, D0.7\n"		\
+		"44:\n"							\
 		"SUB	%0, %0, #4\n"					\
-		"37:\n"							\
+		"45:\n"							\
 		"SETD	[%0++], D0.7\n"					\
 		"SUB	%3, %3, #16\n"					\
 		"1:"							\
@@ -482,7 +498,15 @@
 		"	.long 34b,3b\n"					\
 		"	.long 35b,3b\n"					\
 		"	.long 36b,3b\n"					\
-		"	.long 37b,4b\n"					\
+		"	.long 37b,3b\n"					\
+		"	.long 38b,3b\n"					\
+		"	.long 39b,3b\n"					\
+		"	.long 40b,3b\n"					\
+		"	.long 41b,3b\n"					\
+		"	.long 42b,3b\n"					\
+		"	.long 43b,3b\n"					\
+		"	.long 44b,3b\n"					\
+		"	.long 45b,4b\n"					\
 		"	.previous\n"					\
 		: "=r" (to), "=r" (from), "=r" (ret), "=d" (n)		\
 		: "0" (to), "1" (from), "2" (ret), "3" (n)		\