[PATCH] s390/test_unwind: use raw opcode instead of invalid instruction

[Ilie Halip]

Building with clang & LLVM_IAS=1 leads to an error:
    arch/s390/lib/test_unwind.c:179:4: error: invalid register pair
                        "       mvcl    %%r1,%%r1\n"
                        ^

The test creates an invalid instruction that would trap at runtime, but the
LLVM inline assembler tries to validate it at compile time too.

Use the raw instruction opcode instead.

Link: https://github.com/ClangBuiltLinux/linux/issues/1421
Reported-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Signed-off-by: Ilie Halip <ilie.halip@xxxxxxxxx>
---
 arch/s390/lib/test_unwind.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/s390/lib/test_unwind.c b/arch/s390/lib/test_unwind.c
index cfc5f5557c06..d342bc884b94 100644
--- a/arch/s390/lib/test_unwind.c
+++ b/arch/s390/lib/test_unwind.c
@@ -176,7 +176,7 @@ static noinline int unwindme_func4(struct unwindme *u)
 		 * trigger specification exception
 		 */
 		asm volatile(
-			"	mvcl	%%r1,%%r1\n"
+			"	.insn e,0x0e11\n"	/* mvcl	%%r1,%%r1" */
 			"0:	nopr	%%r7\n"
 			EX_TABLE(0b, 0b)
 			:);
-- 
2.25.1