This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


Re: [Xen-devel] xen-unstable warn_on in msi.c:636

To: "George Dunlap" <George.Dunlap@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] xen-unstable warn_on in msi.c:636
From: "Jan Beulich" <JBeulich@xxxxxxxxxx>
Date: Fri, 29 Jul 2011 15:29:06 +0100
Cc: Olaf Hering <olaf@xxxxxxxxx>, Yunhong Jiang <yunhong.jiang@xxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Fri, 29 Jul 2011 07:29:43 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
>>> On 30.06.11 at 15:31, George Dunlap <George.Dunlap@xxxxxxxxxxxxx> wrote:
> On Thu, Jun 30, 2011 at 1:17 PM, Jan Beulich <JBeulich@xxxxxxxxxx> wrote:
>>>>> On 30.06.11 at 14:03, George Dunlap <George.Dunlap@xxxxxxxxxxxxx> wrote:
>>> Olaf / Jan / all, what do you think of the attached patch, which
>>> teaches the MSI code how to deal with 0 pbas?
>> No, definitely not an option. They simply must not be zero. The
>> problem just is that the BARs for virtual functions all read as zero
>> (and the real value must be calculated from information from the
>> PF's config space).
> But at the moment it IS zero, and this "real value" is simply not
> being calculated.
> I realize this needs to be fixed the Right Way eventually, but at the
> moment anyone who uses SRIOV will have a bunch of scary warnings which
> they can't do anything about except ignore; and it's never a good idea
> to condition people to ignore this kind of warning.
> If the current situation is safe enough that fixing it is a low
> priority, then it's safe enough to remove the warnings for the time
> being.  If it's not safe enough to remove the warnings, then it's not
> safe enough to leave and a fix needs to be a priority.

Attached a patch that eliminates the warnings for me (tested on a single
system only so far). It ought to apply cleanly to current tip of -unstable.


Attachment: x86-msi-vf-bars.patch
Description: Text document

Xen-devel mailing list
<Prev in Thread] Current Thread [Next in Thread>
  • Re: [Xen-devel] xen-unstable warn_on in msi.c:636, Jan Beulich <=