Messages in this thread | | | Subject | Re: [PATCH for 5.2 07/12] rseq/selftests: s390: use trap4 for RSEQ_SIG | From | shuah <> | Date | Thu, 16 May 2019 14:39:28 -0600 |
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Hi Mathieu,
On 4/29/19 9:27 AM, Mathieu Desnoyers wrote: > From: Martin Schwidefsky <schwidefsky@de.ibm.com> > > Use trap4 as the guard instruction for the restartable sequence abort > handler. > > Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> > Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> > --- > 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() >
I generated my pull request for Linus and did a sanity check and ran into merge conflict on this patch. Looks like this is already in Linus's tree.
Can you confirm!
I have to drop this patch and regenerate my pull request. Can you confirm!
thanks, -- Shuah
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