MIPS: lib: memcpy: Restore NOP on delay slot before returning to caller

Commit cf62a8b8134dd3 ("MIPS: lib: memcpy: Use macro to build the
copy_user code") switched to a macro in order to build the memcpy
symbols in preparation for the EVA support. However, this commit
also removed the NOP instruction after the 'jr ra' when returning
back to the caller. This had no visible side-effects since the next
instruction was a load to the t0 register which was already in the
clobbered list, but it may have undesired effects in the future
if some other code is introduced in between the .Ldone and
the .Ll_exc_copy labels.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org> # v3.15+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8512/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/lib/memcpy.S b/arch/mips/lib/memcpy.S
index c17ef80cf65ab0f67946b515c24dab351f684acc..5d3238af9b5cc551ecb0ca9670b242b62f181a73 100644 (file)
--- a/arch/mips/lib/memcpy.S
+++ b/arch/mips/lib/memcpy.S
@@ -503,6 +503,7 @@
        STOREB(t0, NBYTES-2(dst), .Ls_exc_p1\@)
 .Ldone\@:
        jr      ra
+        nop
        .if __memcpy == 1
        END(memcpy)
        .set __memcpy, 0