From: Fiona Ebner <f.ebner@proxmox.com>
To: pve-devel@lists.proxmox.com
Subject: Re: [pve-devel] [PATCH qemu-server] qmeventd: go back to extracting vmid from commandline instead of cgroup file
Date: Mon, 7 Apr 2025 10:32:42 +0200 [thread overview]
Message-ID: <e8978d37-a72e-4d58-87f3-b58457b42d64@proxmox.com> (raw)
In-Reply-To: <20240614092134.18729-1-f.ebner@proxmox.com>
Am 14.06.24 um 11:21 schrieb Fiona Ebner:
> In spirit, this is a revert of 502870a0 ("qmeventd: extract vmid from
> cgroup file instead of cmdline"), but instead of relying on the custom
> 'id' commandline option that's added by a Proxmox VE patch to QEMU,
> rely on the standard 'pidfile' option to extract the VM ID.
>
> As reported in the community forum [0], at least during stop mode
> backup, it seems to be possible to end up with the VM process having
>> 0::/system.slice/pvescheduler.service
> as its single cgroup entry. It's not clear what exactly happens and
> there was no success to reproduce the issue. Might be a rare bug in
> systemd or in pve-common's enter_systemd_scope() code.
>
> This was not the first time relying on the cgroup entry caused issues,
> see d0b58753 ("qmeventd: improve getting VMID from PID in presence of
> legacy cgroup entries").
>
> To avoid such edge cases and issues in the future, go back to
> extracting the VM ID from the process's commandline.
>
> It's enough to care about the first occurrence of the 'pidfile'
> option, because that's the one added by Proxmox VE, so the 'continue's
> in the loop turn into 'break's. Even though a later option would
> override the first for QEMU itself to use, that's not supported
> anyways and the important part is the VM ID which is present in the
> first.
>
> [0]: https://forum.proxmox.com/threads/147409/
>
> Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Ping. After it was quiet for ~10 months, there were 2 new reports about
this yesterday:
https://forum.proxmox.com/threads/147409/post-761580
_______________________________________________
pve-devel mailing list
pve-devel@lists.proxmox.com
https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
next prev parent reply other threads:[~2025-04-07 8:33 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-06-14 9:21 Fiona Ebner
2025-04-07 8:32 ` Fiona Ebner [this message]
2025-04-07 22:53 ` [pve-devel] applied: " Thomas Lamprecht
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=e8978d37-a72e-4d58-87f3-b58457b42d64@proxmox.com \
--to=f.ebner@proxmox.com \
--cc=pve-devel@lists.proxmox.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
Service provided by Proxmox Server Solutions GmbH | Privacy | Legal