From: "Michael S. Tsirkin" <mst@redhat.com>
To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: "Yongji Xie" <elohimes@gmail.com>,
"Marc-André Lureau" <marcandre.lureau@redhat.com>,
"Daniel P. Berrangé" <berrange@redhat.com>,
"Jason Wang" <jasowang@redhat.com>,
"Coquelin, Maxime" <maxime.coquelin@redhat.com>,
"Yury Kotov" <yury-kotov@yandex-team.ru>,
"Евгений Яковлев" <wrfsh@yandex-team.ru>,
nixun@baidu.com, qemu-devel <qemu-devel@nongnu.org>,
lilin24@baidu.com, zhangyu31@baidu.com, chaiwen@baidu.com,
"Xie Yongji" <xieyongji@baidu.com>
Subject: Re: [Qemu-devel] [PATCH v4 for-4.0 0/7] vhost-user-blk: Add support for backend reconnecting
Date: Fri, 11 Jan 2019 12:24:00 -0500 [thread overview]
Message-ID: <20190111122047-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <20190111155342.GA14776@stefanha-x1.localdomain>
On Fri, Jan 11, 2019 at 03:53:42PM +0000, Stefan Hajnoczi wrote:
> I'm concerned that this approach to device recovery is invasive and hard
> to test. Instead I would use VIRTIO's Device Status Field
> DEVICE_NEEDS_RESET bit to tell the guest driver that a reset is
> necessary. This is more disruptive - drivers either have to resubmit or
> fail I/O with EIO - but it's also simple and more likely to work
> correctly (it only needs to be implemented correctly in the guest
> driver, not in the many available vhost-user backend implementations).
>
> Stefan
Unfortunately drivers don't support DEVICE_NEEDS_RESET yet.
I'll be happy to accept patches, but this means we
can't depend on DEVICE_NEEDS_RESET for basic functionality
like reconnect. And given virtio 1.0 has been there
for a while now, I suspect the only way to start using
it is by adding a new feature flag.
Unfortunate but true.
--
MST
next prev parent reply other threads:[~2019-01-11 17:24 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-09 11:27 [Qemu-devel] [PATCH v4 for-4.0 0/7] vhost-user-blk: Add support for backend reconnecting elohimes
2019-01-09 11:27 ` [Qemu-devel] [PATCH v4 for-4.0 1/7] char-socket: Enable "nowait" option on client sockets elohimes
2019-01-10 12:49 ` Daniel P. Berrangé
2019-01-10 13:19 ` Yongji Xie
2019-01-10 13:24 ` Daniel P. Berrangé
2019-01-10 14:08 ` Yongji Xie
2019-01-10 14:11 ` Daniel P. Berrangé
2019-01-10 14:29 ` Yongji Xie
2019-01-10 16:41 ` Daniel P. Berrangé
2019-01-11 7:50 ` Yongji Xie
2019-01-11 8:32 ` Daniel P. Berrangé
2019-01-11 8:36 ` Yongji Xie
2019-01-15 15:39 ` Daniel P. Berrangé
2019-01-15 16:53 ` Yury Kotov
2019-01-15 17:15 ` Daniel P. Berrangé
2019-01-16 5:39 ` Yongji Xie
2019-01-09 11:27 ` [Qemu-devel] [PATCH v4 for-4.0 2/7] vhost-user: Support transferring inflight buffer between qemu and backend elohimes
2019-01-14 22:25 ` Michael S. Tsirkin
2019-01-15 6:46 ` Yongji Xie
2019-01-15 12:54 ` Michael S. Tsirkin
2019-01-15 14:18 ` Yongji Xie
2019-01-18 2:45 ` Yongji Xie
2019-01-09 11:27 ` [Qemu-devel] [PATCH v4 for-4.0 3/7] libvhost-user: Introduce vu_queue_map_desc() elohimes
2019-01-09 11:27 ` [Qemu-devel] [PATCH v4 for-4.0 4/7] libvhost-user: Support tracking inflight I/O in shared memory elohimes
2019-01-11 3:56 ` Jason Wang
2019-01-11 6:10 ` Yongji Xie
2019-01-15 7:52 ` Jason Wang
2019-01-15 14:51 ` Yongji Xie
2019-01-17 9:57 ` Jason Wang
2019-01-17 14:59 ` Michael S. Tsirkin
2019-01-18 3:57 ` Jason Wang
2019-01-18 3:32 ` Yongji Xie
2019-01-18 3:56 ` Michael S. Tsirkin
2019-01-18 3:59 ` Jason Wang
2019-01-18 4:03 ` Michael S. Tsirkin
2019-01-18 7:01 ` Yongji Xie
2019-01-18 9:26 ` Jason Wang
2019-01-19 12:19 ` Yongji Xie
2019-01-15 15:58 ` Michael S. Tsirkin
2019-01-17 10:01 ` Jason Wang
2019-01-17 15:04 ` Michael S. Tsirkin
2019-01-09 11:27 ` [Qemu-devel] [PATCH v4 for-4.0 5/7] vhost-user-blk: Add support to get/set inflight buffer elohimes
2019-01-09 11:27 ` [Qemu-devel] [PATCH v4 for-4.0 6/7] vhost-user-blk: Add support to reconnect backend elohimes
2019-01-09 11:27 ` [Qemu-devel] [PATCH v4 for-4.0 7/7] contrib/vhost-user-blk: enable inflight I/O tracking elohimes
2019-01-10 10:25 ` [Qemu-devel] [PATCH v4 for-4.0 0/7] vhost-user-blk: Add support for backend reconnecting Stefan Hajnoczi
2019-01-10 10:59 ` Yongji Xie
2019-01-11 15:53 ` Stefan Hajnoczi
2019-01-11 17:24 ` Michael S. Tsirkin [this message]
2019-01-12 4:50 ` Yongji Xie
2019-01-14 10:22 ` Stefan Hajnoczi
2019-01-14 10:55 ` Yongji Xie
2019-01-16 14:28 ` Stefan Hajnoczi
2019-01-10 10:39 ` Marc-André Lureau
2019-01-10 11:09 ` Yongji Xie
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=20190111122047-mutt-send-email-mst@kernel.org \
--to=mst@redhat.com \
--cc=berrange@redhat.com \
--cc=chaiwen@baidu.com \
--cc=elohimes@gmail.com \
--cc=jasowang@redhat.com \
--cc=lilin24@baidu.com \
--cc=marcandre.lureau@redhat.com \
--cc=maxime.coquelin@redhat.com \
--cc=nixun@baidu.com \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@gmail.com \
--cc=wrfsh@yandex-team.ru \
--cc=xieyongji@baidu.com \
--cc=yury-kotov@yandex-team.ru \
--cc=zhangyu31@baidu.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.