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author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2019-04-10 12:28:41 +0200 |
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committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2019-04-10 17:48:34 +0200 |
commit | e24e4712efad737ca09ff299276737331cd021d9 (patch) | |
tree | 5255c7d5c603c151f69af3b7051388ea80e9016b /tools/testing/selftests/rseq | |
parent | e91012ee855ad9f5ef2ab106a3de51db93fe4d0c (diff) | |
download | linux-e24e4712efad737ca09ff299276737331cd021d9.tar.bz2 |
s390/rseq: use trap4 for RSEQ_SIG
Use trap4 as the guard instruction for the restartable sequence abort
handler.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'tools/testing/selftests/rseq')
-rw-r--r-- | tools/testing/selftests/rseq/rseq-s390.h | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/tools/testing/selftests/rseq/rseq-s390.h b/tools/testing/selftests/rseq/rseq-s390.h index 1069e85258ce..0afdf7957974 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() |