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From: Jakub Kicinski <kuba@kernel.org>
To: Eric Dumazet <edumazet@google.com>,
	Florian Westphal <fw@strlen.de>, Paolo Abeni <pabeni@redhat.com>,
	Kuniyuki Iwashima <kuniyu@google.com>
Cc: netdev@vger.kernel.org
Subject: deadlocks on pernet_ops_rwsem
Date: Wed, 1 Oct 2025 08:20:36 -0700	[thread overview]
Message-ID: <20251001082036.0fc51440@kernel.org> (raw)

Hi!

We started hitting a deadlock on pernet_ops_rwsem, not very often,
these are the CI branches were we saw it:

 2025-09-18--03-00
 2025-09-18--15-00
 2025-09-18--18-00
 2025-09-19--21-00
 2025-09-21--15-00
 2025-09-21--18-00
 2025-09-22--00-00
 2025-09-22--09-00
 2025-09-23--06-00
 2025-09-24--21-00
 2025-09-27--21-00
 2025-09-28--09-00
 2025-10-01--00-00
 2025-10-01--06-00

First hit seems to be:
https://netdev-3.bots.linux.dev/vmksft-net-dbg/results/302741/65-l2tp-sh/stderr
Two most recent:
https://netdev-3.bots.linux.dev/vmksft-net-dbg/results/321640/110-ip-local-port-range-sh/stderr
https://netdev-3.bots.linux.dev/vmksft-net-dbg/results/321281/63-fdb-notify-sh/stderr

The stack traces aren't very helpful, they mostly show the victim not
who caused the deadlock :(

Any ideas?

             reply	other threads:[~2025-10-01 15:20 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-10-01 15:20 Jakub Kicinski [this message]
2025-10-01 16:46 ` deadlocks on pernet_ops_rwsem Paolo Abeni
2025-10-01 17:22   ` Jakub Kicinski
2025-10-01 18:50     ` Kuniyuki Iwashima
2025-10-01 19:26       ` Jakub Kicinski
2025-10-01 19:33         ` Willem de Bruijn
2025-10-01 20:30           ` Jakub Kicinski

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