Re: FAILED: patch "[PATCH] s390/lib: use expoline for all bcr instructions" failed to apply to 4.14-stable tree

[Martin Schwidefsky <schwidefsky@de.ibm.com>]

On Wed, 12 Sep 2018 21:33:22 +0200
Greg KH <gregkh@linuxfoundation.org> wrote:

> On Mon, Sep 03, 2018 at 05:59:22PM +0200, Martin Schwidefsky wrote:
> > From 4164ae404d145052e20d5a810ca776dd85f25b8b Mon Sep 17 00:00:00 2001
> > From: Martin Schwidefsky <schwidefsky@de.ibm.com>
> > Date: Mon, 6 Aug 2018 13:49:47 +0200
> > Subject: [PATCH] s390/lib: use expoline for all bcr instructions
> > 
> > [ Upstream commit de481fa3f40d7e46f804f1b19d536b390bda5e59 ]  
> 
> That git commit id does not match anything in Linus's tree :(
 
Yes, sure enough that commit id is from our internal devel tree.
Forgot to specify "master" when searching for the commit..

Upstream commit id is 5eda25b10297684c1f46a14199ec00210f3c346e

--
>From e5c91db72e51d0423375f8f73025819b884c0369 Mon Sep 17 00:00:00 2001
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
Date: Mon, 6 Aug 2018 13:49:47 +0200
Subject: [PATCH] s390/lib: use expoline for all bcr instructions

[ Upstream commit 5eda25b10297684c1f46a14199ec00210f3c346e ]

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@vger.kernel.org> # v4.17+
Fixes: 97489e0663 ("s390/lib: use expoline for indirect branches")
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 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

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.