Re: Regression in kernel 3.5 as Dom0 regarding PCI Passthrough?!

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Wed, Jul 25, 2012 at 09:43:57AM -0400, Konrad Rzeszutek Wilk wrote:
> On Wed, Jul 25, 2012 at 02:30:00PM +0200, Tobias Geiger wrote:
> > Hi!
> > 
> > i notice a serious regression with 3.5 as Dom0 kernel (3.4 was rock
> > stable):
> > 
> > 1st: only the GPU PCI Passthrough works, the PCI USB Controller is
> > not recognized within the DomU (HVM Win7 64)
> > Dom0 cmdline is:
> > ro root=LABEL=dom0root xen-pciback.hide=(08:00.0)(08:00.1)(00:1d.0)(00:1d.1)(00:1d.2)(00:1d.7)
> > security=apparmor noirqdebug nouveau.msi=1
> > 
> > Only 8:00.0 and 8:00.1 get passed through without problems, all the
> > USB Controller IDs are not correctly passed through and get a
> > exclamation mark within the win7 device manager ("could not be
> > started").
> 
> Ok, but they do get passed in though? As in, QEMU sees them.
> If you boot a Live Ubuntu/Fedora CD within the guest with the PCI
> passed in devices do you see them? Meaning lspci shows them?
> 
> 
> Is the lspci -vvv output in dom0 different from 3.4 vs 3.5?
> 
> > 
> > 
> > 2nd: After DomU shutdown , Dom0 panics (100% reproducable) - sorry
> > that i have no full stacktrace, all i have is a "screenshot" which i
> > uploaded here:
> > http://imageshack.us/photo/my-images/52/img20120724235921.jpg/
> 
> Ugh, that looks like somebody removed a large chunk of a pagetable.
> 
> Hmm. Are you using dom0_mem=max parameter? If not, can you try
> that and also disable ballooning in the xm/xl config file pls?
> 
> > 
> > 
> > With 3.4 both issues were not there - everything worked perfectly.
> > Tell me which debugging info you need, i may be able to re-install
> > my netconsole to get the full stacktrace (but i had not much luck
> > with netconsole regarding kernel panics - rarely this info gets sent
> > before the "panic"...)

So I am able to reproduce this with a Windows 7 with an ATI 4870 and
an Intel 82574L NIC. The video card still works, but the NIC stopped
working. Same version of hypervisor/toolstack/etc, only change is the
kernel (v3.4.6->v3.5).

Time to get my hands greasy with this..