Re: [Xen-devel] Xen-unstable: pci-passthrough "irq 16: nobody cared" on HVM guest shutdown on irq of device not passed through.

[Sander Eikelenboom <linux@xxxxxxxxxxxxxx>]

Thursday, September 25, 2014, 5:11:33 PM, you wrote:

>>>> On 25.09.14 at 16:36, <linux@xxxxxxxxxxxxxx> wrote:
>> - When shutting down the HVM guest when A happens the number of interrupts 
>> in 
>> /proc/interrups is still what it was, but when B happens it seems like a irq 
>> storm
>>   and after the irq nobody cared that ends with (always that 200000 so 
>> perhaps a threshold ?):
>>   16:     200000          0          0          0          0          0  
>> xen-pirq-ioapic-level  snd_hda_intel

> 100,000 is the traditional threshold, so I would expect the cited
> instance to be the second one. It didn't really become clear to me
> - is this observed in Dom0 or in the shutting down guest? 

This is from the /proc/interrupts of dom0 after the irq nobody cared message 
appeared in dom0 (so after B happened). Just after host boot and first guest 
boot it was stable around 500. On the next start (and after which B would 
happen on shutting the guest down again) it doubled to about 1000 (perhaps when 
the "Unsupported MSI delivery mode 3 for Dom2" occured).

> And did you really check that no other device (even if currently not having
> an interrupt handler bound) is sitting on IRQ 16?

In what way could i check that to be certain ?
(if it's not bound, lspci and /proc/interrupts will probably be insufficient 
for that ?)

>> - On the start when B happens, xl dmesg contains this message (when A 
>> happens 
>> it doesn't contain it):
>>   (XEN) [2014-09-25 13:39:48.149] d32767v2: Unsupported MSI delivery mode 3 
>> for Dom2

> I guess this is what you'd need to start investigating, i.e. where this
> has its origin.


> Jan




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