Re: [regression] KVM: hangs and "irq timeout" booting HURD unless -no-kvm-irqchip passed

[Gleb Natapov <gleb@redhat.com>]

On Mon, Feb 07, 2011 at 02:39:01PM +0200, Avi Kivity wrote:
> On 02/07/2011 08:00 AM, Jonathan Nieder wrote:
> >Hi kvm-ers,
> >
> >When I boot the HURD with
> >
> >	kvm -m 768 -net nic,model=ne2k_pci -net user hurd-installed.qemu
> >
> >it hangs and eventually produces two messages:
> >
> >	hd0: unexpected_intr: status=0x58 { DriveReady SeekComplete DataRequest }
> >	hd0: irq timeout: status=0x58 { DriveReady Seek Complete DataRequest }
> >
> >More details below[1].
> >
> >Adding -no-kvm-irqchip to the kvm command line fixes it --- no
> >more hangs or confusing messages (thanks, Guillem!).
> >
> >Bisects (thanks to Michael for the idea) to
> >
> >	v2.6.37-rc1~142^2~39 (KVM: Check for pending events before
> >	attempting injection, 2010-07-27).
> >
> >Bisection log and kernel configuration available upon request (but
> >probably not too relevant --- the 2.6.37 distro kernel from Debian
> >exhibits the same problem).  Reproducible with kvm/master (2d4b4d26,
> >2011-02-01).
> >
> >CPU is a dual-core AMD Athlon II P360, family 16, model 6.
> >
> >Any hints for tracking this down?  For those wanting to follow along
> >at home, you can find a HURD cd to try at [2].
> >
> 
> Reproduced on AMD, not on Intel.  Given that I see a few PIC and PIT
> PIOs before the hang, the problem is likely at the PIT.  Will look
> further.
> 
I can reproduce it on Intel. Looking into it. Looks like PIC isr_ack
problem again.

--
			Gleb.