[Xen-devel] Debugging passthrough on an S3210SHLC

[Peter Kay <syllopsium@xxxxxxxxxxxxxxxx>]

I'm having difficulty getting any passthrough working on an S3210SHLC (X38 derived S3210 socket 775 server chipset, thus pre SLAT) - this is on the list of supported hardware. Is there any guide as to what can be done - I've tried iommu=verbose, so is the next step sending debug printfs to the xen console? I realise this is a development list so I'd like advice on which bits of source to poke so I can find the root issue.

The hardware does work - I've passed the embedded G200e through using ESXi 5.1 although other devices (a Radeon 6950) don't work.

Issues are - both with XCP1.6 and xen 4.2 (with some small AMD VGA passthrough patches)/xen 4.3 unstable on Debian Wheezy :

Pciback is a module. It recognises the passthrough keyword but PCI IDs are still modified in VMs.

Pt_iomul errors in qemu log even though the status is 'successful'

Xl create errors out with a gnttab error both in 4.2/4.3. Xm works.

When passing through an old 3C900 PCI NIC as a test, this causes noise in the audigy 4 PCI soundcard in the next slot unless that is also passed through. I suspect this is due to the bus layout of the S3210SHLC. Is it always necessary to pass all PCI devices on the same root through? Also should it be necessary/possible to pass a PCI root?

The VMs think the device was successfully passed through (a wheezy hvm binds the appropriate modules and a Windows 7 hvm has seen the radeon) but they don't actually work.

There are so many combinations of hardware and kernel finding out what is wrong is tricky. I'd appreciate some advice diagnosing it.

Hardware is S3210SHLC with latest (52) BIOS, embedded Matrox G200e, two E1000s of some type, a GeForce G210 (for console), Reference AMD 6950 (on the PCH 4x slot as MCH slot bandwidths are restricted for graphics cards), audigy 4 PCI and 3C900.

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