From: Sasha Levin <sashal@kernel.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Zw Tang <shicenci@gmail.com>,
paulmck@kernel.org, peterz@infradead.org, mhiramat@kernel.org,
jiangshanlai@gmail.com, mingo@redhat.com, acme@kernel.org,
namhyung@kernel.org, rcu@vger.kernel.org,
linux-perf-users@vger.kernel.org,
linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org,
mathieu.desnoyers@efficios.com, josh@joshtriplett.org,
bigeasy@linutronix.de, ast@kernel.org, boqun.feng@gmail.com,
mark.rutland@arm.com
Subject: Re: [BUG] RCU stall / hung rcu_gp: process_srcu blocked in synchronize_rcu_normal triggered by perf trace teardown on 7.0.0-rc1
Date: Mon, 2 Mar 2026 12:37:24 -0500 [thread overview]
Message-ID: <aaXK1EV63H6sdG7c@laps> (raw)
In-Reply-To: <20260302112545.51f7e100@gandalf.local.home>
On Mon, Mar 02, 2026 at 11:25:45AM -0500, Steven Rostedt wrote:
>On Mon, 2 Mar 2026 08:36:13 -0500
>Sasha Levin <sashal@kernel.org> wrote:
>
>> This response was AI-generated by bug-bot. The analysis may contain errors — please verify independently.
>>
>> ## Bug Summary
>>
>> This is an RCU stall and hung task deadlock on 7.0.0-rc1, triggered by perf trace teardown under perf interrupt storm conditions. The perf subsystem's tracepoint unregistration path now blocks on SRCU (tracepoint_srcu), which in turn blocks on RCU grace period completion, creating a cascading stall when RCU progress is delayed by perf NMI interrupt storms. Severity: system hang (multiple tasks blocked >143s, eventual complete stall).
>
>Hmm, this analysis corresponds nicely to what I was thinking when looking
>at the stack dumps, but it gives a bit more details than I would have.
Thanks for the feedback!
I'll finish fine-tuning this script, and publish it in a day or two :)
--
Thanks,
Sasha
prev parent reply other threads:[~2026-03-02 17:37 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-02 11:26 [BUG] RCU stall / hung rcu_gp: process_srcu blocked in synchronize_rcu_normal triggered by perf trace teardown on 7.0.0-rc1 Zw Tang
2026-03-02 13:36 ` Sasha Levin
2026-03-02 16:25 ` Steven Rostedt
2026-03-02 17:37 ` Sasha Levin [this message]
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=aaXK1EV63H6sdG7c@laps \
--to=sashal@kernel.org \
--cc=acme@kernel.org \
--cc=ast@kernel.org \
--cc=bigeasy@linutronix.de \
--cc=boqun.feng@gmail.com \
--cc=jiangshanlai@gmail.com \
--cc=josh@joshtriplett.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-perf-users@vger.kernel.org \
--cc=linux-trace-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=mathieu.desnoyers@efficios.com \
--cc=mhiramat@kernel.org \
--cc=mingo@redhat.com \
--cc=namhyung@kernel.org \
--cc=paulmck@kernel.org \
--cc=peterz@infradead.org \
--cc=rcu@vger.kernel.org \
--cc=rostedt@goodmis.org \
--cc=shicenci@gmail.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