From: Anthony Liguori <aliguori@us.ibm.com>
To: Paolo Bonzini <pbonzini@redhat.com>,
Rusty Russell <rusty@rustcorp.com.au>
Cc: Stefan Hajnoczi <stefanha@gmail.com>,
qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@redhat.com>,
"Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [Qemu-devel] [PATCHv2] virtio: verify that all outstanding buffers are flushed
Date: Sun, 16 Dec 2012 14:36:07 -0600 [thread overview]
Message-ID: <87obht7n0o.fsf@codemonkey.ws> (raw)
In-Reply-To: <563127555.23861364.1355471450321.JavaMail.root@redhat.com>
Paolo Bonzini <pbonzini@redhat.com> writes:
>> > We technically should save the addresses and sizes too. It makes
>> > it a heck of a lot safer then re-reading guest memory since we do some
>> > validation on the size of the sg elements.
>>
>> Not really.
>>
>> The guest puts the descriptors in the ring and leaves them there until
>> the device acks. If it changes them once they're exposed but before
>> they're acked, it can get either before or after version, and always
>> could.
>
> The problems start when the guest tries to race against QEMU and defy
> the validation. Always using the validated version is a bit easier
> than redoing the validation after migration.
Exactly.
Regards,
Anthony Liguori
>
> Paolo
next prev parent reply other threads:[~2012-12-16 20:36 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-12-12 10:51 [Qemu-devel] [PATCHv2] virtio: verify that all outstanding buffers are flushed Michael S. Tsirkin
2012-12-12 13:50 ` Stefan Hajnoczi
2012-12-12 14:01 ` Paolo Bonzini
2012-12-12 14:30 ` Michael S. Tsirkin
2012-12-12 14:36 ` Paolo Bonzini
2012-12-12 14:47 ` Michael S. Tsirkin
2012-12-12 15:01 ` Paolo Bonzini
2012-12-12 15:25 ` Michael S. Tsirkin
2012-12-12 15:52 ` Paolo Bonzini
2012-12-12 16:37 ` Michael S. Tsirkin
2012-12-12 16:51 ` Paolo Bonzini
2012-12-12 17:14 ` Michael S. Tsirkin
2012-12-12 17:39 ` Paolo Bonzini
2012-12-12 19:23 ` Michael S. Tsirkin
2012-12-12 21:00 ` Paolo Bonzini
2012-12-12 21:19 ` Michael S. Tsirkin
2012-12-12 21:33 ` Anthony Liguori
2012-12-12 21:51 ` Michael S. Tsirkin
2012-12-14 1:06 ` Rusty Russell
2012-12-14 7:51 ` Paolo Bonzini
2012-12-16 20:36 ` Anthony Liguori [this message]
2012-12-13 7:39 ` Paolo Bonzini
2012-12-13 10:48 ` Kevin Wolf
2012-12-16 16:14 ` Michael S. Tsirkin
2012-12-12 14:26 ` Michael S. Tsirkin
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=87obht7n0o.fsf@codemonkey.ws \
--to=aliguori@us.ibm.com \
--cc=mst@redhat.com \
--cc=pbonzini@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=rusty@rustcorp.com.au \
--cc=stefanha@gmail.com \
--cc=stefanha@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).