From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH v2] kvm: Disable MSI/MSI-X in assigned device reset path
Date: Mon, 16 Apr 2012 19:36:24 +0300
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Cc: Alex Williamson <alex.williamson@redhat.com>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	Avi Kivity <avi@redhat.com>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	"jbaron@redhat.com" <jbaron@redhat.com>
To: Jan Kiszka <jan.kiszka@siemens.com>
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On Mon, Apr 16, 2012 at 06:13:03PM +0200, Jan Kiszka wrote:
> On 2012-04-16 18:08, Michael S. Tsirkin wrote:
> > On Mon, Apr 16, 2012 at 05:10:07PM +0200, Jan Kiszka wrote:
> >> On 2012-04-16 17:06, Michael S. Tsirkin wrote:
> >>> On Mon, Apr 16, 2012 at 08:03:17AM -0600, Alex Williamson wrote:
> >>>> The discussion on this patch seems to have fizzled, with no clear short
> >>>> term solution.
> >>>
> >>> I think we are in concensus, it's just that there are
> >>> multiple bugs still left to fix.
> >>>
> >>> First, we need to prevent guest from touching command
> >>> register except for the bus master bit. Something like
> >>
> >> INTx is harmless as well. Denying access breaks masking for the guest.
> > 
> > We currently mark intx as emulated, no?
> 
> If we use the mask also in the kernel for IRQ sharing, we *monitor* it.
> 
> > Anyway - care fixing it properly?
> 
> There is nothing to fix.
> 
> Jan

Guest access  to command register is a bug.
E.g. it has no business enabling SERR as SERR crashes
host when triggered.

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