Re: Issue about domU missing interrupt

Stefano Stabellini
Wed, 05 Dec 2012 12:07:07 -0000

On Wed, 5 Dec 2012, Sander Eikelenboom wrote:
> Wednesday, December 5, 2012, 12:51:13 PM, you wrote:
>
> > On Tue, 4 Dec 2012, Sander Eikelenboom wrote:
> >> Tuesday, December 4, 2012, 12:01:05 PM, you wrote:
> >>
> >> > On Tue, Dec 04, 2012 at 10:15:58AM +0000, Jan Beulich wrote:
> >> >> >>> On 04.12.12 at 04:07, "G.R."
<firemeteor@users.sourceforge.net> wrote:
> >> >> >>  I had a quick look, and it doesn''t
look that hard to backport that patch.
> >> >> >
> >> >> > Thanks, Mat.
> >> >> > I''m glad to report that the patch do fix my
problem.
> >> >> >
> >> >> > And yest it is really easy to port since the code
did not change across the
> >> >> > two release.
> >> >> > The only change would be line numbers (3841 vs 3803)
and one extra comments
> >> >> > before this line:
> >> >> >
> >> >> >  static int pt_msix_update_one(struct pt_dev *dev,
int entry_nr)
> >> >> >
> >> >> > I''m not sure if you are going to release
another maintenance version that
> >> >> > include this patch,
> >> >> > but I''ll report this to Debain maintainer
since it''s about to freeze for
> >> >> > v7.0 release and v4.2.0 will not make it.
> >> >>
> >> >> Any thoughts on backporting this to 4.1.x, now or after
4.1.4 is
> >> >> out?
> >> >>
> >>
> >> > It''s already in Xen 4.2, it''s confirmed to
fix a bug in Xen 4.1,
> >> > so I''d say it should be a candidate for Xen 4.1.4.
> >>
> >> Just tried switching the device model to "qemu-xen",
seems this one isn''t upstream either.
> >> (XEN) [2012-12-04 22:49:25] vmsi.c:108:d32767 Unsupported delivery
mode 3
> >>
> >> Running xen-unstable as of today, with device-model
"qemu-xen" for this hvm guest.
> >>
>
> > The patch is supposed to fix a bug affecting msi_translate but in
> > upstream QEMU we haven''t implemented msi_translate at all! So
in this
> > case the cause of the bug (and as a consequence the fix) must be a
> > different one.
>
> Ok will see if i can find out what is going on. Probably have to force
msi_translate=0.
>
> I noticed "qemu-xen" doesn''t make a log file in
/var/log/xen as "qemu-dm" does, is this expected ?

No, it is not. You should get the usual /var/log/xen/qemu-dm-domainname.log
file.


> >> Sander
> >>
> >> > -- Pasi
> >>
> >> >> Jan
> >> >>
> >> >> > On Mon, Dec 3, 2012 at 9:58 PM, Mats Petersson
> >> >> > <mats.petersson@citrix.com>wrote:
> >> >> >
> >> >> >> On 03/12/12 13:19, Mats Petersson wrote:
> >> >> >>
> >> >> >>> On 03/12/12 13:14, G.R. wrote:
> >> >> >>>
> >> >> >>>> On Mon, Dec 3, 2012 at 6:15 PM, Mats
Petersson
> >> >> >>>> <mats.petersson@citrix.com
> >> >> >
<mailto:mats.petersson@citrix.**com<mats.petersson@citrix.com>>>
> >> >> >>>> wrote:
> >> >> >>>>
> >> >> >>>>      On 03/12/12 03:47, G.R. wrote:
> >> >> >>>>
> >> >> >>>>          Hi developers,
> >> >> >>>>          I met some domU issues and the
log suggests missing interrupt.
> >> >> >>>>          Details from here:
> >> >> >>>>
http://www.gossamer-threads.**com/lists/xen/users/263938#**
> >> >> >>>> 263938
<http://www.gossamer-threads.com/lists/xen/users/263938#263938>
> >> >> >>>>          In summary, this is the
suspicious log:
> >> >> >>>>
> >> >> >>>>          (XEN) vmsi.c:122:d32767
Unsupported delivery mode 3
> >> >> >>>>
> >> >> >>>>          I''ve checked the code
in question and found that mode 3 is an
> >> >> >>>>          ''reserved_1''
mode.
> >> >> >>>>          I want to trace down the source
of this mode setting to
> >> >> >>>>          root-cause the issue.
> >> >> >>>>          But I''m not an xen
developer, and am even a newbie as a xen
> >> >> >>>> user.
> >> >> >>>>          Could anybody give me
instructions about how to enable
> >> >> >>>>          detailed debug log?
> >> >> >>>>          It could be better if I can get
advice about experiments to
> >> >> >>>>          perform / switches to try out
etc.
> >> >> >>>>
> >> >> >>>>          My SW config:
> >> >> >>>>          dom0: Debian wheezy (3.6
experimental kernel, xen 4.1.3-4)
> >> >> >>>>          domU: Debian wheezy 3.2.x stock
kernel.
> >> >> >>>>
> >> >> >>>>          Thanks,
> >> >> >>>>          Timothy
> >> >> >>>>
> >> >> >>>>      Are you passing hardware (PCI
Passthrough) to the HVM guest?
> >> >> >>>>      What are the exact messages in the
DomU?
> >> >> >>>>
> >> >> >>>>
> >> >> >>>> Yes, I''m doing PCI passthrough
(the IGD, audio && USB controller).
> >> >> >>>> But this is actually a PVHVM guest since
debian stock kernel has PVOP
> >> >> >>>> enabled.
> >> >> >>>> And when I tried another PVOP disabled
linux distro (openelec v2.0), I
> >> >> >>>> did not see such msi related error
message.
> >> >> >>>> Actually, with that domU I do not see
anything obvious wrong from the
> >> >> >>>> log, but I also see nothing from panel
(panel receive no signal and go
> >> >> >>>> power-saving) :-(
> >> >> >>>>
> >> >> >>>>
> >> >> >>>> Back to the issue I was reporting, the
domU log looks like this:
> >> >> >>>>
> >> >> >>>> Dec 2 21:52:44 debvm kernel: [
1085.604071]
> >> >> >>>> [drm:i915_hangcheck_ring_idle]
> >> >> >>>> *ERROR* Hangcheck timer elapsed... blt
ring idle [waiting on 3354, at
> >> >> >>>> 3354], missed IRQ?
> >> >> >>>> Dec 2 21:56:50 debvm kernel: [
1332.076071]
> >> >> >>>> [drm:i915_hangcheck_ring_idle]
> >> >> >>>> *ERROR* Hangcheck timer elapsed...
render ring idle [waiting on 11297, at
> >> >> >>>> 11297], missed IRQ?
> >> >> >>>> Dec 2 22:32:48 debvm kernel: [ 7.220073]
hda-intel: azx_get_response
> >> >> >>>> timeout, switching to polling mode: last
cmd=0x000f0000
> >> >> >>>> Dec 2 22:45:32 debvm kernel: [
776.392084] hda-intel: No response from
> >> >> >>>> codec, disabling MSI: last
cmd=0x002f0600
> >> >> >>>> Dec 2 22:45:33 debvm kernel: [
777.400075] hda_intel: azx_get_response
> >> >> >>>> timeout, switching to single_cmd mode:
last cmd=0x002f0600
> >> >> >>>>
> >> >> >>>>
> >> >> >>>> Thanks,
> >> >> >>>> Timothy
> >> >> >>>>
> >> >> >>> It does sound like there is a fix in 4.2.0,
as indicated by Jan, that
> >> >> >>> fixes this. I''m not fully clued up
to what the policy for backporting
> >> >> >>> fixes are, and I haven''t looked at
the complexity of the fix itself, but
> >> >> >>> either updating to the 4.2.0 or a (personal)
backport sounds like the
> >> >> >>> right solution here.
> >> >> >>>
> >> >> >> I had a quick look, and it doesn''t look
that hard to backport that patch.
> >> >> >>
> >> >> >> --
> >> >> >> Mats
> >> >> >>
> >> >> >>
> >> >> >>> Unfortunately, I hadn''t seen
Jan''s reply by the time I wrote my response
> >> >> >>> to your original email.
> >> >> >>>
> >> >> >>> --
> >> >> >>> Mats
> >> >> >>>
> >> >> >>>
______________________________**_________________
> >> >> >>> Xen-devel mailing list
> >> >> >>> Xen-devel@lists.xen.org
> >> >> >>> http://lists.xen.org/xen-devel
> >> >> >>>
> >> >> >>>
> >> >> >>>
> >> >> >>
> >> >> >>
______________________________**_________________
> >> >> >> Xen-devel mailing list
> >> >> >> Xen-devel@lists.xen.org
> >> >> >> http://lists.xen.org/xen-devel
> >> >> >>
> >> >>
> >> >>
> >> >>
> >> >> _______________________________________________
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> >> >> http://lists.xen.org/xen-devel
> >>
> >>
> >>
>
>