From: Martin Schwidefsky <schwidefsky@de.ibm.com>
Date: Mon, 23 Apr 2018 14:31:36 +0200
Subject: s390/crc32-vx: use expoline for indirect branches
Git-commit: 467a3bf219cee12259182c5cb4821f88fd518a51
Patch-mainline: v4.17-rc6
References: git-fixes f19fbd5ed6
The return from the crc32_le_vgfm_16/crc32c_le_vgfm_16 and the
crc32_be_vgfm_16 functions are done with "br %r14". These are indirect
branches as well and need to use execute trampolines for CONFIG_EXPOLINE=y.
Cc: stable@vger.kernel.org # 4.16
Fixes: f19fbd5ed6 ("s390: introduce execute-trampolines for branches")
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
arch/s390/crypto/crc32be-vx.S | 5 ++++-
arch/s390/crypto/crc32le-vx.S | 4 +++-
2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/arch/s390/crypto/crc32be-vx.S b/arch/s390/crypto/crc32be-vx.S
index e8077f0971f8..2bf01ba44107 100644
--- a/arch/s390/crypto/crc32be-vx.S
+++ b/arch/s390/crypto/crc32be-vx.S
@@ -13,6 +13,7 @@
*/
#include <linux/linkage.h>
+#include <asm/nospec-insn.h>
#include <asm/vx-insn.h>
/* Vector register range containing CRC-32 constants */
@@ -67,6 +68,8 @@
.previous
+ GEN_BR_THUNK %r14
+
.text
/*
* The CRC-32 function(s) use these calling conventions:
@@ -203,6 +206,6 @@ ENTRY(crc32_be_vgfm_16)
.Ldone:
VLGVF %r2,%v2,3
- br %r14
+ BR_EX %r14
.previous
diff --git a/arch/s390/crypto/crc32le-vx.S b/arch/s390/crypto/crc32le-vx.S
index d8c67a58c0c5..7d6f568bd3ad 100644
--- a/arch/s390/crypto/crc32le-vx.S
+++ b/arch/s390/crypto/crc32le-vx.S
@@ -14,6 +14,7 @@
*/
#include <linux/linkage.h>
+#include <asm/nospec-insn.h>
#include <asm/vx-insn.h>
/* Vector register range containing CRC-32 constants */
@@ -76,6 +77,7 @@
.previous
+ GEN_BR_THUNK %r14
.text
@@ -264,6 +266,6 @@ crc32_le_vgfm_generic:
.Ldone:
VLGVF %r2,%v2,2
- br %r14
+ BR_EX %r14
.previous