Re: FreeBSD Dom0 IOMMU issues (resent)

["Chen, Tiejun" <tiejun.chen@intel.com>]

On 2015/5/7 0:46, Michael Dexter wrote:
>
> Hello all,
>
> (Resend: I cropped out too much and have added 'pciconf -lv' output)
>
> I have been working with Roger Pau Monne to bring FreeBSD Dom0 support
> to a production-ready state but we appear to have hit an IOMMU issue.
>
> Hardware: Lenovo ThinkPad T420 i7-2640M CPU @ 2.80GHz with 16GB RAM.
>
> I am attaching my console logs which first show my loader.conf file the
> DomU .cfg file and then DomU boot with Xorg starting.

I just feel this resembles one known problem but I'm not 100% sure, so 
just please take a try,

#1. Disable interrupt message generation

diff --git a/xen/drivers/passthrough/vtd/iommu.c 
b/xen/drivers/passthrough/vtd/iommu.c
index 1248a17..f0915d7 100644
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -2018,7 +2018,7 @@ static int init_vtd_hw(void)
          clear_fault_bits(iommu);

          spin_lock_irqsave(&iommu->register_lock, flags);
-        dmar_writel(iommu->reg, DMAR_FECTL_REG, 0);
+        dmar_writel(iommu->reg, DMAR_FECTL_REG, DMA_FECTL_IM);
          spin_unlock_irqrestore(&iommu->register_lock, flags);
      }

>
> In the end I get:
>
> (XEN) ****************************************
> (XEN) Panic on CPU 2:
> (XEN) queue invalidate wait descriptor was not executed
> (XEN) ****************************************
>
> Please let me know if you want me to try any configuration changes.
>

#2.

Please add 'cpuidle=0 msi=1'.

Thanks
Tiejun