From: Jens Axboe <[email protected]>
To: Ju Hyung Park <[email protected]>, [email protected]
Subject: Re: io_uring possibly the culprit for qemu hang (linux-5.4.y)
Date: Wed, 30 Sep 2020 21:03:20 -0600 [thread overview]
Message-ID: <[email protected]> (raw)
In-Reply-To: <CAD14+f3G2f4QEK+AQaEjAG4syUOK-9bDagXa8D=RxdFWdoi5fQ@mail.gmail.com>
On 9/30/20 10:26 AM, Ju Hyung Park wrote:
> Hi everyone.
>
> I have recently switched to a setup running QEMU 5.0(which supports
> io_uring) for a Windows 10 guest on Linux v5.4.63.
> The QEMU hosts /dev/nvme0n1p3 to the guest with virtio-blk with
> discard/unmap enabled.
>
> I've been having a weird issue where the system would randomly hang
> whenever I turn on or shutdown the guest. The host will stay up for a
> bit and then just hang. No response on SSH, etc. Even ping doesn't
> work.
>
> It's been hard to even get a log to debug the issue, but I've been
> able to get a show-backtrace-all-active-cpus sysrq dmesg on the most
> recent encounter with the issue and it's showing some io_uring
> functions.
>
> Since I've been encountering the issue ever since I switched to QEMU
> 5.0, I suspect io_uring may be the culprit to the issue.
>
> While I'd love to try out the mainline kernel, it's currently not
> feasible at the moment as I have to stay in linux-5.4.y. Backporting
> mainline's io_uring also seems to be a non-trivial job.
>
> Any tips would be appreciated. I can build my own kernel and I'm
> willing to try out (backported) patches.
I'll see if I can reproduce this, thanks for the report!
--
Jens Axboe
next prev parent reply other threads:[~2020-10-01 3:03 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-30 16:26 io_uring possibly the culprit for qemu hang (linux-5.4.y) Ju Hyung Park
2020-10-01 3:03 ` Jens Axboe [this message]
2020-10-01 8:59 ` Stefano Garzarella
2020-10-01 13:47 ` Jack Wang
2020-10-01 14:30 ` Ju Hyung Park
2020-10-02 7:34 ` Stefano Garzarella
2020-10-16 18:04 ` Ju Hyung Park
2020-10-16 18:07 ` Jens Axboe
2020-10-17 14:29 ` Ju Hyung Park
2020-10-17 15:02 ` Jens Axboe
2020-10-19 9:22 ` Pankaj Gupta
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 \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
/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