Re: [Xen-devel] VT-d faults with Integrated Intel graphics on 4.6

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

On 8/27/2015 12:19 AM, Malcolm Crossley wrote:
> On 25/08/15 15:43, Konrad Rzeszutek Wilk wrote:
> > On Tue, Aug 25, 2015 at 02:55:31PM +0800, Chen, Tiejun wrote:
> > > On 8/25/2015 8:19 AM, Tamas K Lengyel wrote:
> > > > Hi everyone,
> > > > I saw some people passingly mention this on the list before but just in
> > > > case it has been missed, my serial is also being spammed with the following
> > > > printouts with both Xen 4.6 RC1 and the latest staging build:
> > > >
> > > > ...
> > > > (XEN) [VT-D]DMAR:[DMA Read] Request device [0000:00:02.0] fault addr
> > > > 33487d7000, iommu reg = ffff82c000201000
> > > > (XEN) [VT-D]DMAR: reason 06 - PTE Read access is not set
> > > > (XEN) [VT-D]DMAR:[DMA Read] Request device [0000:00:02.0] fault addr
> > > > 33487d7000, iommu reg = ffff82c000201000
> > > > (XEN) [VT-D]DMAR: reason 06 - PTE Read access is not set
> > > > (XEN) [VT-D]DMAR:[DMA Read] Request device [0000:00:02.0] fault addr
> > > > 33487d7000, iommu reg = ffff82c000201000
> > > > (XEN) [VT-D]DMAR: reason 06 - PTE Read access is not set
> > > > (XEN) [VT-D]DMAR:[DMA Read] Request device [0000:00:02.0] fault addr
> > > > 33487d7000, iommu reg = ffff82c000201000
> > > > (XEN) [VT-D]DMAR: reason 06 - PTE Read access is not set
> > > > (XEN) [VT-D]DMAR:[DMA Read] Request device [0000:00:02.0] fault addr
> > > > 2610742000, iommu reg = ffff82c000201000
> > > > (XEN) [VT-D]DMAR: reason 07 - Next page table ptr is invalid
> > > > ...
> I think this problem is caused by missing IOMMU mappings for the RMRR regions
> if the domain does not have shared EPT enabled. This includes PV Dom 0.
I don't think this is relevant to current problem.

> I have posted a patch to fix the issue:
>
> http://lists.xen.org/archives/html/xen-devel/2015-08/msg02090.html
And we already fixed this on 4.6.

Thanks
Tiejun

> > > What's your platform? BDW? And how much memory is set to your guest OS?
> > Is see this as well. But oddly enough - only when I use the AMT feature
> > (normally I just use serial console on the machine).
> >
> > The platform is             /DQ67SW, BIOS
> > SWQ6710H.86A.0066.2012.1105.1504 11/05/2012
> >
> > There is no guest OS - this is initial domain. And I boot with 2GB:
> >  Released 0 page(s)
> >
> > Xen: [mem 0x0000000000000000-0x0000000000099fff] usable
> > Xen: [mem 0x000000000009a800-0x00000000000fffff] reserved
> > Xen: [mem 0x0000000000100000-0x000000001fffffff] usable
> > Xen: [mem 0x0000000020000000-0x00000000201fffff] reserved
> > Xen: [mem 0x0000000020200000-0x000000003fffffff] usable
> > Xen: [mem 0x0000000040000000-0x00000000401fffff] reserved
> > Xen: [mem 0x0000000040200000-0x0000000080465fff] usable
> > Xen: [mem 0x0000000080466000-0x000000009e855fff] unusable
> > Xen: [mem 0x000000009e856000-0x000000009e85efff] ACPI data
> > Xen: [mem 0x000000009e85f000-0x000000009e8a9fff] ACPI NVS
> > Xen: [mem 0x000000009e8aa000-0x000000009e8b1fff] unusable
> > Xen: [mem 0x000000009e8b2000-0x000000009e9a4fff] reserved
> > Xen: [mem 0x000000009e9a5000-0x000000009e9a6fff] unusable
> > Xen: [mem 0x000000009e9a7000-0x000000009ebc5fff] reserved
> > Xen: [mem 0x000000009ebc6000-0x000000009ebc6fff] unusable
> > Xen: [mem 0x000000009ebc7000-0x000000009ebd6fff] reserved
> > Xen: [mem 0x000000009ebd7000-0x000000009ebf4fff] ACPI NVS
> > Xen: [mem 0x000000009ebf5000-0x000000009ec18fff] reserved
> > Xen: [mem 0x000000009ec19000-0x000000009ec5bfff] ACPI NVS
> > Xen: [mem 0x000000009ec5c000-0x000000009ee7bfff] reserved
> > Xen: [mem 0x000000009ee7c000-0x000000009effffff] unusable
> > Xen: [mem 0x000000009f800000-0x00000000bf9fffff] reserved
> > Xen: [mem 0x00000000fec00000-0x00000000fec00fff] reserved
> > Xen: [mem 0x00000000fed1c000-0x00000000fed3ffff] reserved
> > Xen: [mem 0x00000000fed90000-0x00000000fed91fff] reserved
> > Xen: [mem 0x00000000fee00000-0x00000000feefffff] reserved
> > Xen: [mem 0x00000000ff000000-0x00000000ffffffff] reserved
> > Xen: [mem 0x0000000100000000-0x000000043e5fffff] unusable
> >
> > > Just at first glance to fault address, this seems be issued from some
> > > known erratas on BDS and SKL.
> > I am runnig v4.2-rc8.
> > > Thanks
> > > Tiejun
> > >
> > > > The device in question is an integrated Intel graphics card:
> > > >
> > > > 00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core
> > > > Processor Family Integrated Graphics Controller (rev 09)
> > Same device..
> This is a sandy bridge device which doesn't support shared EPT for GPU device.
>
>
> > > > The only way I found to stop the messages from making my serial connection
> > > > useless was by assigning the device to xen-pciback.
> This will cause the GPU to be reset and the reset stopped the GPU accessing the
> RMRR region.
>
> > > > Cheers,
> > > > Tamas
> > > >
> > > >
> > > >
> > > > _______________________________________________
> > > > Xen-devel mailing list
> > > > Xen-devel@xxxxxxxxxxxxx
> > > > http://lists.xen.org/xen-devel
> > > _______________________________________________
> > > Xen-devel mailing list
> > > Xen-devel@xxxxxxxxxxxxx
> > > http://lists.xen.org/xen-devel
> > _______________________________________________
> > Xen-devel mailing list
> > Xen-devel@xxxxxxxxxxxxx
> > http://lists.xen.org/xen-devel
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel