From: Marcelo Tosatti <mtosatti@redhat.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: kvm@vger.kernel.org, Alex Williamson <alex.williamson@redhat.com>,
Jan Kiszka <jan.kiszka@siemens.com>, Avi Kivity <avi@redhat.com>
Subject: Re: [PATCHv4] device-assignment: don't touch pci command register
Date: Wed, 18 Apr 2012 23:12:39 -0300 [thread overview]
Message-ID: <20120419021239.GA17648@amt.cnet> (raw)
In-Reply-To: <20120417121042.GA24138@redhat.com>
On Tue, Apr 17, 2012 at 03:10:42PM +0300, Michael S. Tsirkin wrote:
> Real command register is under kernel control:
> it includes bits for triggering SERR, marking
> BARs as invalid and such which are all under host
> kernel control.
>
> While there's no known bug this triggers - since qemu does its
> best to make guest state match device state -
> it seems safer to avoid touching this register as much as
> possible.
>
> With this patch, we don't touch any bits
> except bus master which is ok to put under guest control
> and intx mask which kvm interrupt sharing machinery
> explicitly allows.
>
> Note: PCI_STATUS bears looking into as well.
>
> Tested-by: Alex Williamson <alex.williamson@redhat.com>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Applied, thanks.
prev parent reply other threads:[~2012-04-19 2:16 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-04-17 12:10 [PATCHv4] device-assignment: don't touch pci command register Michael S. Tsirkin
2012-04-17 18:15 ` Alex Williamson
2012-04-17 18:37 ` Jan Kiszka
2012-04-19 2:12 ` Marcelo Tosatti [this message]
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=20120419021239.GA17648@amt.cnet \
--to=mtosatti@redhat.com \
--cc=alex.williamson@redhat.com \
--cc=avi@redhat.com \
--cc=jan.kiszka@siemens.com \
--cc=kvm@vger.kernel.org \
--cc=mst@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