From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [KVM PATCH v8 3/3] KVM: add iosignalfd support
Date: Tue, 23 Jun 2009 14:36:34 +0300
Message-ID: <20090623113634.GC17635@redhat.com>
References: <20090619002224.15859.97977.stgit@dev.haskins.net> <20090619003045.15859.73197.stgit@dev.haskins.net> <20090623085633.GA16294@redhat.com> <4A40BD73.8050902@novell.com>
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To: Gregory Haskins <ghaskins@novell.com>
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On Tue, Jun 23, 2009 at 07:33:07AM -0400, Gregory Haskins wrote:
> Michael S. Tsirkin wrote:
> > On Thu, Jun 18, 2009 at 08:30:46PM -0400, Gregory Haskins wrote:
> >   
> >> +static int
> >> +iosignalfd_group_in_range(struct kvm_io_device *this, gpa_t addr, int len,
> >> +			  int is_write)
> >> +{
> >> +	struct _iosignalfd_group *p = to_group(this);
> >> +
> >> +	return ((addr >= p->addr && (addr < p->addr + p->length)));
> >> +}
> >>     
> >
> > I think I see a problem here. For virtio, we do not necessarily want all
> > virtqueues for a device to live in kernel: there might be control
> > virtqueues that we want to leave in userspace. Since this claims all
> > writes to a specific address, the signal never makes it to userspace.
> >
> >   
> You can use a wildcard.  Would that work?
> 

Nope, you need to know the value written.