Hi Andrew

Am 14.08.13 19:30, schrieb Andrew Cooper:
[...]
> Do you have the boot time dmesg output?
Sure, please see the attached log file. Please note that this dmesg data 
comes from a system that I have booted from the standard XEN 4.2.2 
kernel (i.e. w/o the WARN() statement and the various printk statements 
I have added; furthermore this was w/o the serial console being active)

>
> The problem here is that a queued_invalidate wait descriptor has been
> issued, and has not been completed within 1 second.  In all previous
> cases I have debugged, this is actually because we already turned off
> the IOMMU, then tried to turn it off again.
>
> Could you perhaps try with this patch as well?
>
> diff --git a/xen/drivers/passthrough/vtd/iommu.c
> b/xen/drivers/passthrough/vtd/iommu.c
> index 071a91b..45fff48 100644
> --- a/xen/drivers/passthrough/vtd/iommu.c
> +++ b/xen/drivers/passthrough/vtd/iommu.c
> @@ -791,6 +791,9 @@ static void iommu_disable_translation(struct iommu
> *iommu)
>       u32 sts;
>       unsigned long flags;
>
> +    printk("**Debug: Disabling translation for iommu %"PRId32"\n",
> iommu->index);
> +    WARN();
> +
>       /* apply platform specific errata workarounds */
>       vtd_ops_preamble_quirk(iommu);
I'll get back to you in due course with the log output after I have 
applied the patch and restarted & then shutdown XEN again.

>
>
> ~Andrew
>