From: Thomas Gleixner <tglx@kernel.org>
To: Matthieu Baerts <matttbe@kernel.org>,
Peter Zijlstra <peterz@infradead.org>
Cc: "Jiri Slaby" <jirislaby@kernel.org>,
"Stefan Hajnoczi" <stefanha@redhat.com>,
"Stefano Garzarella" <sgarzare@redhat.com>,
kvm@vger.kernel.org, virtualization@lists.linux.dev,
Netdev <netdev@vger.kernel.org>,
rcu@vger.kernel.org, "MPTCP Linux" <mptcp@lists.linux.dev>,
"Linux Kernel" <linux-kernel@vger.kernel.org>,
"Shinichiro Kawasaki" <shinichiro.kawasaki@wdc.com>,
"Paul E. McKenney" <paulmck@kernel.org>,
"Dave Hansen" <dave.hansen@linux.intel.com>,
luto@kernel.org, "Michal Koutný" <MKoutny@suse.com>,
"Waiman Long" <longman@redhat.com>,
"Marco Elver" <elver@google.com>
Subject: Re: Stalls when starting a VSOCK listening socket: soft lockups, RCU stalls, timeout
Date: Tue, 10 Mar 2026 14:47:35 +0100 [thread overview]
Message-ID: <87v7f3re2w.ffs@tglx> (raw)
In-Reply-To: <a5cabf68-df88-4a5e-8075-bb10debc44f7@kernel.org>
On Tue, Mar 10 2026 at 14:40, Matthieu Baerts wrote:
> On 10/03/2026 13:28, Thomas Gleixner wrote:
>
> (...)
>
>> I've updated the debug patch and removed the @users conditionals so it
>> keeps searching. So it should find that magic 73.
>
> It looks like it does, thank you! I just tried this new debug patch, and
> I managed to boot 100 times without issues, while before I was getting
> it after max 20 attempts. I left the test running to boot up to 1000
> times, just in case.
Now that I actually understood the problem, I was able to write a
reproducer which triggers the issue 100% reliable.
The debug patch does cure it and it does the right thing. I have a
better version of that in testing right now which avoid all that flaky
accounting and especially in the vfork() case the full tasklist walk.
I'll send out a complete patch series with changelogs etc. later.
Thanks a lot for your patience and invaluable help. Very appreciated!
tglx
next prev parent reply other threads:[~2026-03-10 13:47 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-06 11:54 Stalls when starting a VSOCK listening socket: soft lockups, RCU stalls, timeout Matthieu Baerts
2026-02-06 16:38 ` Stefano Garzarella
2026-02-06 17:13 ` Matthieu Baerts
2026-02-26 10:37 ` Jiri Slaby
2026-03-02 5:28 ` Jiri Slaby
2026-03-02 11:46 ` Peter Zijlstra
2026-03-02 14:30 ` Waiman Long
2026-03-05 7:00 ` Jiri Slaby
2026-03-05 11:53 ` Jiri Slaby
2026-03-05 12:20 ` Jiri Slaby
2026-03-05 16:16 ` Thomas Gleixner
2026-03-05 17:33 ` Jiri Slaby
2026-03-05 19:25 ` Thomas Gleixner
2026-03-06 5:48 ` Jiri Slaby
2026-03-06 9:57 ` Thomas Gleixner
2026-03-06 10:16 ` Jiri Slaby
2026-03-06 16:28 ` Thomas Gleixner
2026-03-06 11:06 ` Matthieu Baerts
2026-03-06 16:57 ` Matthieu Baerts
2026-03-06 18:31 ` Jiri Slaby
2026-03-06 18:44 ` Matthieu Baerts
2026-03-06 21:40 ` Matthieu Baerts
2026-03-06 15:24 ` Peter Zijlstra
2026-03-07 9:01 ` Thomas Gleixner
2026-03-07 22:29 ` Thomas Gleixner
2026-03-08 9:15 ` Thomas Gleixner
2026-03-08 16:55 ` Jiri Slaby
2026-03-08 16:58 ` Thomas Gleixner
2026-03-08 17:23 ` Matthieu Baerts
2026-03-09 8:43 ` Thomas Gleixner
2026-03-09 12:23 ` Matthieu Baerts
2026-03-10 8:09 ` Thomas Gleixner
2026-03-10 8:20 ` Thomas Gleixner
2026-03-10 8:56 ` Jiri Slaby
2026-03-10 9:00 ` Jiri Slaby
2026-03-10 10:03 ` Thomas Gleixner
2026-03-10 10:06 ` Thomas Gleixner
2026-03-10 11:24 ` Matthieu Baerts
2026-03-10 11:54 ` Peter Zijlstra
2026-03-10 12:28 ` Thomas Gleixner
2026-03-10 13:40 ` Matthieu Baerts
2026-03-10 13:47 ` Thomas Gleixner [this message]
2026-03-10 15:51 ` Matthieu Baerts
2026-03-03 13:23 ` Matthieu Baerts
2026-03-05 6:46 ` Jiri Slaby
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=87v7f3re2w.ffs@tglx \
--to=tglx@kernel.org \
--cc=MKoutny@suse.com \
--cc=dave.hansen@linux.intel.com \
--cc=elver@google.com \
--cc=jirislaby@kernel.org \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=longman@redhat.com \
--cc=luto@kernel.org \
--cc=matttbe@kernel.org \
--cc=mptcp@lists.linux.dev \
--cc=netdev@vger.kernel.org \
--cc=paulmck@kernel.org \
--cc=peterz@infradead.org \
--cc=rcu@vger.kernel.org \
--cc=sgarzare@redhat.com \
--cc=shinichiro.kawasaki@wdc.com \
--cc=stefanha@redhat.com \
--cc=virtualization@lists.linux.dev \
/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