Re: [PATCH 05/15] Coalesce userspace/kernel irqchip interrupt injection logic.

[Gleb Natapov <gleb@redhat.com>]

On Wed, Apr 15, 2009 at 12:22:34PM +0200, Jan Kiszka wrote:
> Gleb Natapov wrote:
> > On Wed, Apr 15, 2009 at 01:30:29PM +0400, Dmitry Eremin-Solenikov wrote:
> >> 2009/4/14 Gleb Natapov <gleb@redhat.com>:
> >>> On Tue, Apr 14, 2009 at 11:29:49PM +0400, Dmitry Eremin-Solenikov wrote:
> >>>> 2009/4/14 Gleb Natapov <gleb@redhat.com>:
> >>>>> On Tue, Apr 14, 2009 at 06:32:29PM +0400, Dmitry Eremin-Solenikov wrote:
> >>>>>> 2009/4/14 Gleb Natapov <gleb@redhat.com>:
> >>>>>>> On Tue, Apr 14, 2009 at 02:14:04PM +0000, Dmitry Eremin-Solenikov wrote:
> >>>>>>>> Gleb Natapov wrote:
> >>>>>>>>
> >>>>>>>>> Start to use interrupt/exception queues like VMX does. This also fix the
> >>>>>>>>> bug that if exit was caused by a guest internal exception access to IDT
> >>>>>>>>> the exception was not reinjected.
> >>>>>>>> This patch broke KVM for me: after it is applied (to the tip of avi's git tree),
> >>>>>>>> linux inside KVM (version 84 from Debian) stops booting, moaning about lost
> >>>>>>>> interrupts from ide. The KVM is executed inside qemu-system-x86_64,
> >>>>>>>> version 0.10.2.
> >>>>>>>>
> >>>>>>> Please apply next patch in the series too. This one will not work
> >>>>>>> without it. But better yet can you please test entire series.
> >>>>>> After applying the next patch (or the whole serie), I get the following messages
> >>>>>> during initramfs drivers probe:
> >>>>>>
> >>>>>> Clocksource tsc unstable (delta...)
> >>>>>> no cont in shutdown!
> >>>>>> floppy0: FDC access conflict!
> >>>>>>
> >>>>>> Then kernel boot stalls. I'll try gdbing into kernel but this may
> >>>>>> require lots of efforts.
> >>>>>> I don't quite understand how do these two patches influence FDC emulation, but
> >>>>>> they do. Tell me if you need any additional info.
> >>>>>>
> >>>>> What guest is this? What kernel? Does the whole series works?
> >>>> Guest: Debian lenny. Linux 2.6.26, Debian version (I can provide
> >>>> config or bzImage + initrd).
> >>> Yes please provide. Debian lenny (x86_64) is my default guest :) And I
> >>> just booted it fine on AMD barcelona CPU.  What is you host cpu?
> >>> "cat /proc/cpuinfo"
> >> qemu-x86_64 version 0.10.2 running on i386
> >> Due to problems with qemu-x86_64 I have to boot the 'host' kernel with 'noapic'.
> >> qemu-64:~# cat /proc/cpuinfo
> >> processor       : 0
> >> vendor_id       : AuthenticAMD
> >> cpu family      : 6
> >> model           : 2
> >> model name      : QEMU Virtual CPU version 0.10.2
> >> stepping        : 3
> >> cpu MHz         : 1828.754
> >> cache size      : 512 KB
> >> fpu             : yes
> >> fpu_exception   : yes
> >> cpuid level     : 2
> >> wp              : yes
> >> flags           : fpu de pse tsc msr pae mce cx8 apic sep mtrr pge mca
> >> cmov pat pse36 clflush mmx fxsr sse sse2 syscall nx lm 3dnowext 3dnow
> >> up pni svm
> >> bogomips        : 3700.32
> >> TLB size        : 1024 4K pages
> >> clflush size    : 64
> >> cache_alignment : 64
> >> address sizes   : 40 bits physical, 48 bits virtual
> >> power management:
> >>
> >>
> > I need _host_ cpu info. Do the same on the host please.
> 
> That _is_ his host - qemu in emulation mode (ie. nested virtualization).
Ah, now I noticed svm in cpu flags. Does qemu support svm in TCG?

> Maybe there is an issue with qemu's emulation of svm or, rather, with
> the apic emulation. The fact that he has to boot the first-level guest
> with noapic is fairly suspicious.
> 
> Dmitry, what is your first level-guest distro/kernel, also Lenny? And
> what is the top-level qemu command line? Let's focus on this first,
> leaving KVM and this patch series aside for a while.
> 
If KVM runs inside a guest that is definitely a good idea :)

--
			Gleb.