Re: [Xen-devel] Xen4.2 S3 regression?

[Ben Guthro <ben@xxxxxxxxxx>]

Additionally - I was able to use this patch on its own, without any of
the prior debug patch - which, as you pointed out before, ended up
being unnecessary.

On Thu, Sep 6, 2012 at 7:48 AM, Ben Guthro <ben@xxxxxxxxxx> wrote:
> Fantastic!
>
> Initial tests are very good, with this dma_msi_ack modification.
>
> I've been able to get past the ahci stall, and run through ~10 suspend
> / resume cycles with this fix.
> Additional tests are warranted, and I'll run through an automated
> sleep / wake script I have to make sure this fix holds over time.
>
> Thanks for this.
>
> Ben
>
> On Thu, Sep 6, 2012 at 6:22 AM, Jan Beulich <JBeulich@xxxxxxxx> wrote:
>>>>> On 04.09.12 at 14:27, Ben Guthro <ben@xxxxxxxxxx> wrote:
>>> I've put the console log of this test run here:
>>> https://citrix.sharefile.com/d/sdc383e252fb41c5a
>>>
>>> (again, so as not to clog everyone's inbox)
>>>
>>> I have not yet gone through the log in its entirety yet, but thought I
>>> would first send it to you to see if you had something in particular
>>> you were looking for.
>>>
>>> The file name is console-S3-MSI.txt
>>
>> I think that nailed it: pci_restore_msi_state() passed a pointer
>> to the stored entry->msg to write_msi_msg(), but with interrupt
>> remapping enabled that function's call to
>> iommu_update_ire_from_msi() alters the passed in struct
>> msi_msg instance. As the stored value is used for nothing but
>> a subsequent (second) restore, a problem would only arise if
>> between the two saves to further writing of the stored entry
>> would occur (i.e. no intermediate call to set_msi_affinity()).
>>
>> Attached the advertised next version of the debugging patch
>> (printks - slightly altered - left in to catch eventual further
>> problems or to deal with my analysis being wrong; none of the
>> "bogus!" ones should now trigger anymore). If this works, I'd
>> be curious to see how much of your other workaround code
>> you could then remove without breaking things again.
>>
>> Jan
>>

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel