Re: arm: warning at virt/kvm/arm/vgic.c:1468

[Jan Kiszka <jan.kiszka@web.de>]

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On 2015-02-15 14:37, Marc Zyngier wrote:
> On Sun, Feb 15 2015 at  8:53:30 am GMT, Jan Kiszka <jan.kiszka@web.de> wrote:
>> I'm now throwing trace_printk at my broken KVM. Already found out that I
>> get ARM_EXCEPTION_IRQ every few 10 µs. Not seeing any irq_* traces,
>> though. Weird.
> 
> This very much looks like a screaming interrupt. At such a rate, no
> wonder your VM make much progress. Can you find out which interrupt is
> screaming like this? Looking at GICC_HPPIR should help, but you'll have
> to map the CPU interface in HYP before being able to access it there.

OK... let me figure this out. I had this suspect as well - the host gets
a VM exit for each injected guest IRQ?

BTW, I also tried with in-kernel GIC disabled (in the kernel config),
but I guess that's pointless. Linux seems to be stuck on a
non-functional architectural timer then, right?

> 
> Do you have an form of power-management on this system?

Just killed every config that has PM for FREQ in its name, but that
makes no difference.

Jan



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