From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: qemu/hw/device-assignment: questions about msix_table_page
Date: Tue, 5 May 2009 12:51:36 +0300
Message-ID: <20090505095136.GA12797@redhat.com>
References: <20090427104117.GB29082@redhat.com> <200904272203.59909.sheng@linux.intel.com> <20090427141504.GC2504@redhat.com> <200904272230.18253.sheng@linux.intel.com>
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Cc: Avi Kivity <avi@redhat.com>, Marcelo Tosatti <mtosatti@redhat.com>,
	kvm@vger.kernel.org
To: Sheng Yang <sheng@linux.intel.com>
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On Mon, Apr 27, 2009 at 10:30:17PM +0800, Sheng Yang wrote:
> > > > > If guest can write to the real device MSI-X table directly, it would
> > > > > cause chaos on interrupt delivery, for what guest see is totally
> > > > > different with what's host see...
> > > >
> > > > Obviously.
> > > >
> > > > Thanks,
> 

What's the reason that this page is unmapped from the qemu memory space?
Specifically what do these lines do:
            int offset = r_dev->msix_table_addr - real_region->base_addr;
            ret = munmap(region->u.r_virtbase + offset, TARGET_PAGE_SIZE);

-- 
MST