4.9-stable review patch. If anyone has any objections, please let me know.
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From: Martin Schwidefsky schwidefsky@de.ibm.com
[ Upstream commit 97489e0663fa700d6e7febddc43b58df98d7bcda ]
The return from the memmove, memset, memcpy, __memset16, __memset32 and __memset64 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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/s390/lib/mem.S | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
--- a/arch/s390/lib/mem.S +++ b/arch/s390/lib/mem.S @@ -6,6 +6,9 @@
#include <linux/linkage.h> #include <asm/export.h> +#include <asm/nospec-insn.h> + + GEN_BR_THUNK %r14
/* * memset implementation @@ -39,7 +42,7 @@ ENTRY(memset) .Lmemset_clear_rest: larl %r3,.Lmemset_xc ex %r4,0(%r3) - br %r14 + BR_EX %r14 .Lmemset_fill: stc %r3,0(%r2) cghi %r4,1 @@ -56,7 +59,7 @@ ENTRY(memset) .Lmemset_fill_rest: larl %r3,.Lmemset_mvc ex %r4,0(%r3) - br %r14 + BR_EX %r14 .Lmemset_xc: xc 0(1,%r1),0(%r1) .Lmemset_mvc: @@ -79,7 +82,7 @@ ENTRY(memcpy) .Lmemcpy_rest: larl %r5,.Lmemcpy_mvc ex %r4,0(%r5) - br %r14 + BR_EX %r14 .Lmemcpy_loop: mvc 0(256,%r1),0(%r3) la %r1,256(%r1)