[Xen-devel] Q77 IGD instantly crashes on xen-pciback bind.

["Dr. Greg Wettstein" <greg@xxxxxxxxxxxxxxxxx>]

Hi, hope the week is ending well for everyone.

As readers of the list may remember we've kept the ATI primary adapter
passthrough patches current for qemu-traditional on Xen for a number
of years.  Our 'run-passthrough' utility for binding/unbind devices
and running a Windows guest with passthrough have enjoyed a tidy
number of downloads through the years as well.

We are taking on a passthrough project and in the process upgrading
our infrastructure to 4.4.x.  We also need to take on the issue of
passing Intel IGD adapters through to a windows guest.  We are
currently working on an Intel Q77 (DQ77KB) board in preparation for
moving to Q87 boards.

The Intel display adapter is showing up as the standard 00:02.0 PCI
device and things go south pretty quickly.  We create a slot for the
device on the pciback driver and as soon as we bind the device the
machine goes out like a light, no logs or diagnostics, just instantly
stone dead.

This issue is invariant over pciback in vpci or passthrough modes.  It
also occurs instantly when the pciback assignment is made with 'xl
pci-assignable-add'.

We will throw a '#define DEBUG 1' in the top of all the xen-pciback
driver code and see if we can get more information out of it.  I just
wanted to get this in front of the list in case this is a well known
issue or we are headed into other problems we should know about.

I'm assuming that qemu-traditional will handle an IGD primary
passthrough.  If any of the Intel guys are reading this give me a
shout with some directions/advice if we need to roll up our sleeves
and modify the device emulator.

At least it is an "Outlaw Josey Whales bug', not hard to track, leaves
dead machines wherever it goes... :-)

Best wishes for a pleasant weekend to everyone.

Greg

As always,
Dr. G.W. Wettstein, Ph.D.   Enjellic Systems Development, LLC.
4206 N. 19th Ave.           Specializing in information infra-structure
Fargo, ND  58102            development.
PH: 701-281-1686
FAX: 701-281-3949           EMAIL: greg@xxxxxxxxxxxx
------------------------------------------------------------------------------
"The cynics are right nine times out of ten."
                                -- H. L. Mencken

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