From 0700eab4df5b9231fe89e9c575eb45ea561d1f7f Mon Sep 17 00:00:00 2001 From: Ilie Halip Date: Wed, 17 Nov 2021 19:48:21 +0200 Subject: [PATCH] s390/test_unwind: use raw opcode instead of invalid instruction [ Upstream commit 53ae7230918154d1f4281d7aa3aae9650436eadf ] 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. Reported-by: Nick Desaulniers Signed-off-by: Ilie Halip Reviewed-by: Nick Desaulniers Suggested-by: Ulrich Weigand Link: https://github.com/ClangBuiltLinux/linux/issues/1421 Link: https://lore.kernel.org/r/20211117174822.3632412-1-ilie.halip@gmail.com Reviewed-by: Christian Borntraeger Signed-off-by: Christian Borntraeger [hca@linux.ibm.com: use illegal opcode, and update comment] Signed-off-by: Heiko Carstens Signed-off-by: Sasha Levin --- arch/s390/lib/test_unwind.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/s390/lib/test_unwind.c b/arch/s390/lib/test_unwind.c index ecf327d..c0635cf 100644 --- a/arch/s390/lib/test_unwind.c +++ b/arch/s390/lib/test_unwind.c @@ -171,10 +171,11 @@ static noinline int unwindme_func4(struct unwindme *u) } /* - * trigger specification exception + * Trigger operation exception; use insn notation to bypass + * llvm's integrated assembler sanity checks. */ asm volatile( - " mvcl %%r1,%%r1\n" + " .insn e,0x0000\n" /* illegal opcode */ "0: nopr %%r7\n" EX_TABLE(0b, 0b) :); -- 2.7.4