On Tue, Feb 19, 2013 at 4:41 PM, Michael S. Tsirkin <m...@redhat.com> wrote: > On Thu, Feb 14, 2013 at 08:23:04PM +0200, Avi Kivity wrote: >> On Thu, Feb 14, 2013 at 8:12 PM, Michael S. Tsirkin <m...@redhat.com> wrote: >> >> >> >> Is there an actual real problem that needs fixing? >> > >> > Yes. Guests sometimes cause device BARs to temporary overlap >> > the APIC range during BAR sizing. It works fine on a physical >> > system but fails on KVM since pci has same priority. >> > >> > See the report: >> > [BUG] Guest OS hangs on boot when 64bit BAR present >> > >> >> Is PCI_COMMAND_MEMORY set while this is going on? > > I think Linux never clears PCI_COMMAND_MEMORY because > it's buggy in some devices.
Ok. Then I recommend defining the MSI message area as overlapped with sufficient priority. It should probably be a child of the PCI address space. The IOAPIC is actually closer to ISA, but again it's sufficient to move it to the PCI address space. I doubt its priority matters.
