From: sashiko-bot@kernel.org
To: "Thomas Richter" <tmricht@linux.ibm.com>
Cc: linux-s390@vger.kernel.org, "Vasily Gorbik" <gor@linux.ibm.com>,
"Christian Borntraeger" <borntraeger@linux.ibm.com>,
"Heiko Carstens" <hca@linux.ibm.com>,
"Alexander Gordeev" <agordeev@linux.ibm.com>
Subject: Re: [PATCH 3/3 v8] s390/pai: Support CPU hotplug for PMU PAI
Date: Tue, 01 Sep 2026 09:03:30 +0000 [thread overview]
Message-ID: <20260901090331.0B6891F000E9@smtp.kernel.org> (raw)
In-Reply-To: <20260901085448.2260658-4-tmricht@linux.ibm.com>
> The command 'perf stat -e pai_crypto/CRYPTO_ALL/ -- <command>'
> crashes the kernel when CPUs are hotplug added during that run.
>
> Root cause is the missing allocation of per-CPU data structures
> for that new CPU. The allocation is dynamic and the first
> event that has task context creates such a structure for
> each online CPU. This is not sufficient. CPUs may be offline
> during event creation and can be set online during the
> perf run time. For example commands
>
> # echo 0 > /sys/devices/system/cpu/cpu1/online
> # perf stat -e cycles -i -- stress-ng -t10s --matrix X
> # sleep 1
> # echo 1 > /sys/devices/system/cpu/cpu1/online
>
> [ ... ]
>
> Cc: stable@vger.kernel.org # v6.19
> Fixes: 582cc1b28e8c ("s390/pai_ext: Enable per-task and system-wide sampling event")
> Fixes: 9f66572f2889 ("s390/pai_crypto: Enable per-task and system-wide sampling event")
> Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Sashiko has reviewed this patch and found no issues. It looks great!
--
Sashiko AI review · https://sashiko.dev/#/patchset/20260901085448.2260658-1-tmricht@linux.ibm.com?part=3
next prev parent reply other threads:[~2026-09-01 9:03 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-01 8:54 [PATCH 0/3 v8] Add CPU hotplug support for PAI PMU Thomas Richter
2026-09-01 8:54 ` [PATCH 1/3 v8] s390/pai: Use PAI PMU index as parameter replacing event Thomas Richter
2026-09-01 9:12 ` sashiko-bot
2026-09-01 9:56 ` Thomas Richter
2026-09-01 8:54 ` [PATCH 2/3 v8] s390/pai: Move locking to event init and delete Thomas Richter
2026-09-01 9:12 ` sashiko-bot
2026-09-01 8:54 ` [PATCH 3/3 v8] s390/pai: Support CPU hotplug for PMU PAI Thomas Richter
2026-09-01 9:03 ` sashiko-bot [this message]
2026-09-01 11:19 ` Heiko Carstens
2026-09-01 14:20 ` [PATCH 0/3 v8] Add CPU hotplug support for PAI PMU Heiko Carstens
2026-09-01 14:22 ` Heiko Carstens
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260901090331.0B6891F000E9@smtp.kernel.org \
--to=sashiko-bot@kernel.org \
--cc=agordeev@linux.ibm.com \
--cc=borntraeger@linux.ibm.com \
--cc=gor@linux.ibm.com \
--cc=hca@linux.ibm.com \
--cc=linux-s390@vger.kernel.org \
--cc=sashiko-reviews@lists.linux.dev \
--cc=tmricht@linux.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox