linux-block.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Matteo Croce <mcroce@linux.microsoft.com>
To: Prasanna Kalever <pkalever@redhat.com>
Cc: Ming Lei <ming.lei@redhat.com>,
	Prasanna Kumar Kalever <prasanna.kalever@redhat.com>,
	linux-kernel@vger.kernel.org, linux-block@vger.kernel.org,
	nbd@other.debian.org, Josef Bacik <josef@toxicpanda.com>,
	Jens Axboe <axboe@kernel.dk>, Ilya Dryomov <idryomov@redhat.com>,
	Xiubo Li <xiubli@redhat.com>,
	Lennart Poettering <lennart@poettering.net>,
	Luca Boccassi <bluca@debian.org>
Subject: Re: [PATCH] nbd: provide a way for userspace processes to identify device backends
Date: Wed, 19 May 2021 16:33:19 +0200	[thread overview]
Message-ID: <CAFnufp3ZzrKHiV1Vy9_bAymy0oEr288dL4yWo4EjqUzhJV6J-A@mail.gmail.com> (raw)
In-Reply-To: <CANwsLLH0HyZ-VGPMc+VmuLivG1fiZHnSqUyLx3UWb76ZMCgYSg@mail.gmail.com>

On Tue, May 18, 2021 at 9:52 AM Prasanna Kalever <pkalever@redhat.com> wrote:
> > BTW, loop has similar issue, and patch of 'block: add a sequence number to disks'
> > is added for addressing this issue, what do you think of that generic
> > approach wrt. this nbd's issue? such as used the exposed sysfs sequence number
> > for addressing this issue?
> >
> > https://lore.kernel.org/linux-block/YH81n34d2G3C4Re+@gardel-login/#r
>
> If I understand the changes and the background of the fix correctly, I
> think with that fix author is trying to monotonically increase the seq
> number and add it to the disk on every single device map/attach and
> expose it through the sysfs, which will help the userspace processes
> further to correlate events for particular and specific devices that
> reuse the same loop device.
>

Yes, but nothing prevents to use diskseq in nbd, and increase it on reconfigure.
That would allow to detect if the device has been reconfigured.

Regards,
-- 
per aspera ad upstream

  parent reply	other threads:[~2021-05-19 14:33 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-29 10:28 [PATCH] nbd: provide a way for userspace processes to identify device backends Prasanna Kumar Kalever
2021-04-30  2:14 ` Xiubo Li
2021-05-17 14:42   ` Prasanna Kalever
2021-05-18  0:29 ` Ming Lei
2021-05-18  7:52   ` Prasanna Kalever
2021-05-18  9:24     ` Ming Lei
2021-05-18  9:49       ` Prasanna Kalever
2021-05-19  7:54         ` Ming Lei
2021-05-19 14:17           ` Prasanna Kalever
2021-05-19 14:33     ` Matteo Croce [this message]
2021-05-26 14:13       ` Matteo Croce
2021-05-27  5:22         ` Prasanna Kalever
2021-06-16  8:42 ` Prasanna Kalever
2021-06-16 12:59 ` Jens Axboe

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=CAFnufp3ZzrKHiV1Vy9_bAymy0oEr288dL4yWo4EjqUzhJV6J-A@mail.gmail.com \
    --to=mcroce@linux.microsoft.com \
    --cc=axboe@kernel.dk \
    --cc=bluca@debian.org \
    --cc=idryomov@redhat.com \
    --cc=josef@toxicpanda.com \
    --cc=lennart@poettering.net \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=ming.lei@redhat.com \
    --cc=nbd@other.debian.org \
    --cc=pkalever@redhat.com \
    --cc=prasanna.kalever@redhat.com \
    --cc=xiubli@redhat.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;
as well as URLs for NNTP newsgroup(s).