[PATCH 4.9 011/153] MIPS: Handle microMIPS jumps in the same way as MIPS32/MIPS64 jumps

From: Greg Kroah-Hartman
Date: Fri Mar 10 2017 - 06:35:33 EST

4.9-stable review patch. If anyone has any objections, please let me know.


From: Paul Burton <paul.burton@xxxxxxxxxx>

commit 096a0de427ea333f56f0ee00328cff2a2731bcf1 upstream.

is_jump_ins() checks for plain jump ("j") instructions since commit
e7438c4b893e ("MIPS: Fix sibling call handling in get_frame_info") but
that commit didn't make the same change to the microMIPS code, leaving
it inconsistent with the MIPS32/MIPS64 code. Handle the microMIPS
encoding of the jump instruction too such that it behaves consistently.

Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
Fixes: e7438c4b893e ("MIPS: Fix sibling call handling in get_frame_info")
Cc: Tony Wu <tung7970@xxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
Patchwork: https://patchwork.linux-mips.org/patch/14533/
Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

arch/mips/kernel/process.c | 2 ++
1 file changed, 2 insertions(+)

--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -293,6 +293,8 @@ static inline int is_jump_ins(union mips
return 0;

+ if (ip->j_format.opcode == mm_j32_op)
+ return 1;
if (ip->j_format.opcode == mm_jal32_op)
return 1;
if (ip->r_format.opcode != mm_pool32a_op ||