From: Martin Schwidefsky <[email protected]> Use trap4 as the guard instruction for the restartable sequence abort handler.
Signed-off-by: Martin Schwidefsky <[email protected]> Signed-off-by: Mathieu Desnoyers <[email protected]> --- tools/testing/selftests/rseq/rseq-s390.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/rseq/rseq-s390.h b/tools/testing/selftests/rseq/rseq-s390.h index 7c4f3a70b6c7..1d05c5187ae6 100644 --- a/tools/testing/selftests/rseq/rseq-s390.h +++ b/tools/testing/selftests/rseq/rseq-s390.h @@ -1,6 +1,13 @@ /* SPDX-License-Identifier: LGPL-2.1 OR MIT */ -#define RSEQ_SIG 0x53053053 +/* + * RSEQ_SIG uses the trap4 instruction. As Linux does not make use of the + * access-register mode nor the linkage stack this instruction will always + * cause a special-operation exception (the trap-enabled bit in the DUCT + * is and will stay 0). The instruction pattern is + * b2 ff 0f ff trap4 4095(%r0) + */ +#define RSEQ_SIG 0xB2FF0FFF #define rseq_smp_mb() __asm__ __volatile__ ("bcr 15,0" ::: "memory") #define rseq_smp_rmb() rseq_smp_mb() -- 2.11.0
