Re: [Qemu-devel] [PATCH][v13] megasas: LSI Megaraid SAS HBA emulation

[Michael S. Tsirkin]

On Tue, Feb 21, 2012 at 11:27:15AM +0100, Hannes Reinecke wrote:
> On 02/21/2012 12:04 AM, Michael S. Tsirkin wrote:
> > On Mon, Feb 20, 2012 at 04:17:05PM +0100, Alexander Graf wrote:
> >>
> >> On 20.02.2012, at 16:16, Hannes Reinecke wrote:
> >>
> >>> On 02/20/2012 04:13 PM, Alexander Graf wrote:
> >>>>
> >>>> On 20.02.2012, at 16:11, Hannes Reinecke wrote:
> >>>>
> >>>>> This patch adds an emulation for the LSI Megaraid SAS 8708EM2 HBA.
> >>>>> I've tested it to work with Linux, Windows Vista, and Windows7.
> >>>>>
> >>>>> Changes since v12:
> >>>>> - Fixup flag setting via properties
> >>>>> - Disable MSI-X per default
> >>>>> - Fixup MSI-X handling
> >>>>
> >>>> If MSI-X works again, why disable it? :o Does it break in other cases?
> >>>>
> >>> It doesn't. No idea why.
> >>> That's why I disabled it :-)
> >>>
> >>> The MSI-X vector is signalled, but nothing on the OS side appear to
> >>> receive it.
> >>> If you got any idea on how to debug it I'm all ears ...
> >>
> >> Michael, any ideas? IIRC MSI-X used to work in earlier versions, so 
> >> something recent must've broken it.
> >>
> >>
> >> Alex
> > 
> > Hmm, there were's any recent changes I'm aware of.
> > Try to check that MSIX vector as qemu sees it
> > matches the value that the guest set.
> > If using kvm, compare against kernel as well.
> > Endian-ness issue somehow?
> > Are you testing on x86?
> > 
> Testing on x86_64.
> But apparently the (linux) driver doesn't activate MSI-X.
> So either I didn't set it up properly in the HBA emulation
> or something else went wrong.
> 
> Cheers,
> 
> Hannes

Ah, the driver doesn't enable msix? Your earlier comment
made me think the driver did enable it, and you
send the interrupt but guest does not get it...

Look at output of lspci -vv in the guest. If you see
msix there, then we present msix capability,
look at what failure did driver detect.

> -- 
> Dr. Hannes Reinecke                 zSeries & Storage
> address@hidden                              +49 911 74053 688
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