Re: [Xen-devel] [PATCH v3 0/4] x86/iommu: PVH Dom0 workarounds for missing RMRR entries

[Roger Pau Monné <roger.pau@xxxxxxxxxx>]

On Tue, Aug 07, 2018 at 10:45:32AM -0600, Tamas K Lengyel wrote:
> On Tue, Aug 7, 2018 at 10:04 AM Tamas K Lengyel
> <tamas.k.lengyel@xxxxxxxxx> wrote:
> (XEN) [VT-D]iommu.c:919: iommu_fault_status: Fault Overflow
> (XEN) [VT-D]iommu.c:921: iommu_fault_status: Primary Pending Fault
> (XEN) [VT-D]DMAR:[DMA Read] Request device [0000:00:02.0] fault addr
> 428f926000, iommu reg = ffff82c000a0c000
> (XEN) [VT-D]DMAR: reason 06 - PTE Read access is not set
> (XEN) print_vtd_entries: iommu #0 dev 0000:00:02.0 gmfn 428f926
> (XEN)     root_entry[00] = 43aaae001
> (XEN)     context[10] = 2_43cf92001
> (XEN)     l4[000] = 9c0000043cf91107
> (XEN)     l3[10a] = 8000000000000000
> (XEN)     l3[10a] not present
> 
> The fault is repeated a million times per second and the system is
> pretty much stalled.

As Jan says, this page is outside of any range in the memory map. I
wonder however what's in there.

I think (also seeing the PV issues) you should bring this up with the
driver maintainers, it might actually be a bug that the driver is
trying to access such address.

In the meantime, you can try to add to the command line:

rmrr=0x428f926=0:0:2.0

In order to force an iommu mapping of this address.

Thanks, Roger.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel