linux-kernel - Re: Debugging stuck mount

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <dc25520d-e068-49bd-9faa-07c6f6928c35@app.fastmail.com>
Date: Fri, 09 Aug 2024 09:39:41 +0200
From: "Morten Hein Tiljeset" <morten@...jeset.com>
To: "Christian Brauner" <brauner@...nel.org>
Cc: linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: Debugging stuck mount

> The file descriptor could already be closed but the task could be stuck
> exiting and so queued task work including destroying files wouldn't be
> done yet. You could also try and see if you can figure out what tasks
> require your workload to do a lazy umount in the first place. That might
> bring you closer to the root cause.
>
> What kernel version are you running anyway?
That's an interesting idea about the stuck task, I'll try looking into that. We're not
doing lazy unmounts on purpose -- I'm only concluding that it must be happening based on
the mount namespace being NULL. I wonder if the lazy unmount could happen implicitly
as a consequence of some other operation?

I'm on kernel 6.1.53 and I've also experienced the problem on the 5.15.x series.