Re: [Xen-devel] About passing through USB devices in HVM domain

["陈诚" <concretechen@xxxxxxxxx>]

Sorry, at point 3 I missed the the dump information.
It seems to follow the way:
do_IRQ()
__do_IRQ()
note_interrupt()
__report_bad_irq
That is more than 99900 interrupts out of 100000 are unhandled.

2008/3/20, Alex Novik <alex@xxxxxxxxxxxx>:
> A.ok.
> B. 1.It doesn't matter if it is generating interrupt itself or not. The 
> problem is? as soon as pt device generates interrupt it will go to DOM0, 
> which is unable to handle this interrupt. Results in interrupt storming.
> 2. Do you do this before or after binding? Anyway, the simplest way to do it, 
> is just rmmod the driver from dom0 before running hvm. Try it pls. Just to 
> make sure..
> 3. I'm not positive about svm. We didn't try it. But your problem sounds like 
> if interrupt is not reaching hvm or hvm is not able to access the device to 
> clear the interrupt. Try to verify that interrupt was sent to hvm (prints or 
> whatever you're using). The good point to start is inside pt_intr_assist. It 
> does the injection, verify that this is happeneing...
> 4. Hopefully, you didn't forget to make changes to irq.c as well, do you?
>
> -----Original Message-----
> From: 陈诚 [mailto:concretechen@xxxxxxxxx]
> Sent: Thursday, March 20, 2008 1:53 PM
> To: Alex Novik; xen-devel@xxxxxxxxxxxxxxxxxxx
> Subject: Re: [Xen-devel] About passing through USB devices in HVM domain
>
> Hi,
> a. The OHCI USB Controller has 4K MMIO region and it is aligned in DOM0.
> b. Yes, but 1) the device that sharing this IRQ line never generate any 
> interrupts (it is the HDA device) 2) when we bind the interrupt, we free any 
> sharing IRQs explicitly in Xen by calling free_irq
>
> We even 1-to-1 mapped the MMIO region.
>
> The Neo patch adds a call to pt_intr_assist() between pt_update_irq() and 
> hvm_set_callback_irq_level() in vmx_intr_assist(), since we are using SVM, we 
> add the call to pt_intr_assist() between pt_update_irq() and 
> hvm_set_callback_irq_level() in svm_intr_assist().
> // We have extracted the changes in the Neo patch and appied it to the 
> standard Xen-3.1 version
>
> Thank you.
>
>
>
> 2008/3/20, Alex Novik <alex@xxxxxxxxxxxx>:
> >  Hi,
> >   I'm one of the guys who is responsible for this patch. So, let's try
> > to understand what's happening there...
> >   1. I'd like you to check following things for me:
> >     a. Is your USB controller has mmio space aligned? Look at the
> > lspci in DOM0 and verify that all MMIO spaces are aligned to 4kb. If
> > not, fix it manually (with setpci), if it helps look for mmio
> > alignment patch for DOM0.
> >     b. Do you have any devices, beside USB on the same IRQ line? "cat
> > /proc/interrupts/ " will show you this. If you do, it comes to another
> > problem, which we called interdomain sharing. Look for the discussion
> > related to that issue and apply patch. To verify that this is the
> > problem, just remove drivers of all the devices that are using the
> > same IRQ () I'm pretty positive that your interrupt storming related
> > to one of this two issues.
> > Anyway, keep me informed.
> > Best regards,
> >  Alex.
> >
> >
> >
> >
> > -----Original Message-----
> > From: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
> > [mailto:xen-devel-bounces@xxxxxxxxxxxxxxxxxxx] On Behalf Of ??
> > Sent: Thursday, March 20, 2008 10:50 AM
> > To: xen-devel
> > Subject: [Xen-devel] About passing through USB devices in HVM domain
> >
> > HI,
> >    We are currently trying to pass through the USB controller (OHCI)
> > using 1-to-1 mapping domain (mainly based on the Neo-1-to-1 patch) on
> > a Non-VT-d machine. If we do not plug in any devices, the HVM works
> > fine, but as long as we plug in one USB device, the HVM domain
> > crashes.
> >    From the serial output we find that interrupts keep firing at the
> > IRQ line that was passed through. The Neo-1-to-1 patch uses a so
> > called CPA (change polarity algorithm) to handle interrupt pass
> > through, we are not very clear about this idea and even why it should
> > be done. Should any body explain it to us, that will be very helpful.
> >    We are also trying to pass through an IEEE 1394 OHCI Controller,
> > under FC6 HVM domain, it keeps on firing interrupts after the boot
> > process goes to udev step, which crashes the system. It is even worse
> > under WinXP, it crashes the system and makes permanent damage to the
> > QEMU disk image, we have know idea why this happens.
> >    By the way, we are using an AMD processor with SVM support.
> >    Thank you.
> >
> > Cheers
> >
> > ConcreteChen@xxxxxxxxx
> >
> > _______________________________________________
> > Xen-devel mailing list
> > Xen-devel@xxxxxxxxxxxxxxxxxxx
> > http://lists.xensource.com/xen-devel
> >
>

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel