>From 4164ae404d145052e20d5a810ca776dd85f25b8b Mon Sep 17 00:00:00 2001
From: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Date: Mon, 6 Aug 2018 13:49:47 +0200
Subject: [PATCH] s390/lib: use expoline for all bcr instructions
[ Upstream commit de481fa3f40d7e46f804f1b19d536b390bda5e59 ]
The memove, memset, memcpy, __memset16, __memset32 and __memset64
function have an additional indirect return branch in form of a
"bzr" instruction. These need to use expolines as well.
Cc: <stable@xxxxxxxxxxxxxxx> # v4.17+
Fixes: 97489e0663 ("s390/lib: use expoline for indirect branches")
Reviewed-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
---
arch/s390/lib/mem.S | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/arch/s390/lib/mem.S b/arch/s390/lib/mem.S
index e1fa974ac500..37e52118d7e9 100644
--- a/arch/s390/lib/mem.S
+++ b/arch/s390/lib/mem.S
@@ -17,7 +17,7 @@
ENTRY(memmove)
ltgr %r4,%r4
lgr %r1,%r2
- bzr %r14
+ jz .Lmemmove_exit
aghi %r4,-1
clgr %r2,%r3
jnh .Lmemmove_forward
@@ -36,6 +36,7 @@ ENTRY(memmove)
.Lmemmove_forward_remainder:
larl %r5,.Lmemmove_mvc
ex %r4,0(%r5)
+.Lmemmove_exit:
BR_EX %r14
.Lmemmove_reverse:
ic %r0,0(%r4,%r3)
@@ -65,7 +66,7 @@ EXPORT_SYMBOL(memmove)
*/
ENTRY(memset)
ltgr %r4,%r4
- bzr %r14
+ jz .Lmemset_exit
ltgr %r3,%r3
jnz .Lmemset_fill
aghi %r4,-1
@@ -80,12 +81,13 @@ ENTRY(memset)
.Lmemset_clear_remainder:
larl %r3,.Lmemset_xc
ex %r4,0(%r3)
+.Lmemset_exit:
BR_EX %r14
.Lmemset_fill:
stc %r3,0(%r2)
cghi %r4,1
lgr %r1,%r2
- ber %r14
+ je .Lmemset_fill_exit
aghi %r4,-2
srlg %r3,%r4,8
ltgr %r3,%r3
@@ -97,6 +99,7 @@ ENTRY(memset)
.Lmemset_fill_remainder:
larl %r3,.Lmemset_mvc
ex %r4,0(%r3)
+.Lmemset_fill_exit:
BR_EX %r14
.Lmemset_xc:
xc 0(1,%r1),0(%r1)
@@ -111,7 +114,7 @@ EXPORT_SYMBOL(memset)
*/
ENTRY(memcpy)
ltgr %r4,%r4
- bzr %r14
+ jz .Lmemcpy_exit
aghi %r4,-1
srlg %r5,%r4,8
ltgr %r5,%r5
@@ -120,6 +123,7 @@ ENTRY(memcpy)
.Lmemcpy_remainder:
larl %r5,.Lmemcpy_mvc
ex %r4,0(%r5)
+.Lmemcpy_exit:
BR_EX %r14
.Lmemcpy_loop:
mvc 0(256,%r1),0(%r3)
--
2.16.4
