From: Stefan Hajnoczi <stefanha@redhat.com>
To: Eduardo Habkost <ehabkost@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Peter Krempa <pkrempa@redhat.com>,
qemu-block@nongnu.org, "Michael S. Tsirkin" <mst@redhat.com>,
libvir-list@redhat.com, Markus Armbruster <armbru@redhat.com>,
qemu-devel@nongnu.org, Max Reitz <mreitz@redhat.com>,
Christoph Hellwig <hch@lst.de>,
"Dr . David Alan Gilbert" <dgilbert@redhat.com>
Subject: Re: [PATCH] virtio-blk: drop deprecated scsi=on|off property
Date: Tue, 4 May 2021 15:32:55 +0100 [thread overview]
Message-ID: <YJFbFztA61itLoR2@stefanha-x1.localdomain> (raw)
In-Reply-To: <20210429180352.ohhfz4kwyxapbiyl@habkost.net>
[-- Attachment #1: Type: text/plain, Size: 1098 bytes --]
On Thu, Apr 29, 2021 at 02:03:52PM -0400, Eduardo Habkost wrote:
> On Thu, Apr 29, 2021 at 04:52:21PM +0100, Stefan Hajnoczi wrote:
> > Live migrating old guests from an old QEMU with the SCSI feature bit
> > enabled will fail with "Features 0x... unsupported. Allowed features:
> > 0x...". We've followed the QEMU deprecation policy so users have been
> > warned...
> >
>
> Were they really warned, though? People running
> "-machine pc-i440fx-2.4" might be completely unaware that it was
> silently enabling a deprecated feature.
>
> Can we have this documented in a more explicit way? Maybe just a
> comment at hw_compat_2_4 would be enough, to warn people doing
> backports and rebases downstream.
>
> Can we make QEMU refuse to start if using pc-2.4 + virtio-blk
> together, just to be sure?
On second thought, do we really want to break pc-2.4 user's QEMU
command-lines if they have a virtio-blk device?
BTW Peter mentioned libvirt avoids the unnecessary scsi=off:
https://gitlab.com/libvirt/libvirt/-/commit/ec69f0190be731d12faeac08dbf63325836509a9
Stefan
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]
next prev parent reply other threads:[~2021-05-04 14:34 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-29 15:52 [PATCH] virtio-blk: drop deprecated scsi=on|off property Stefan Hajnoczi
2021-04-29 16:16 ` Peter Krempa
2021-05-04 14:31 ` Stefan Hajnoczi
2021-04-29 18:03 ` Eduardo Habkost
2021-04-30 7:42 ` Markus Armbruster
2021-04-30 7:58 ` Peter Krempa
2021-05-04 10:45 ` Dr. David Alan Gilbert
2021-05-04 14:28 ` Stefan Hajnoczi
2021-05-04 14:32 ` Stefan Hajnoczi [this message]
2021-05-04 15:26 ` Eduardo Habkost
2021-04-30 5:47 ` Michal Prívozník
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=YJFbFztA61itLoR2@stefanha-x1.localdomain \
--to=stefanha@redhat.com \
--cc=armbru@redhat.com \
--cc=dgilbert@redhat.com \
--cc=ehabkost@redhat.com \
--cc=hch@lst.de \
--cc=kwolf@redhat.com \
--cc=libvir-list@redhat.com \
--cc=mreitz@redhat.com \
--cc=mst@redhat.com \
--cc=pkrempa@redhat.com \
--cc=qemu-block@nongnu.org \
--cc=qemu-devel@nongnu.org \
/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).