PV on HVM guest hang...

[Mukesh Rathor <mukesh.rathor@oracle.com>]

I'm debugging a hang of 64bit HVM guest with PV drivers. The problem happens 
during migrate. So far I've discovered that the guest is stuck in loop 
receiving interrupt 0xa9/169. In the hypervisor I see that upon vmx exit, it 
sends 0xa9 right away...

(XEN)    [<ffff828c80152680>] vlapic_test_and_set_irr+0x0/0x40   :0xa9
(XEN)    [<ffff828c80151d35>] ioapic_inj_irq+0x95/0x150
(XEN)    [<ffff828c801521d0>] vioapic_deliver+0x3e0/0x440
(XEN)    [<ffff828c801522df>] vioapic_update_EOI+0xaf/0xc0
(XEN)    [<ffff828c8015394b>] vlapic_write+0x2eb/0x7e0
(XEN)    [<ffff828c8014a630>] hvm_mmio_intercept+0xa0/0x360
(XEN)    [<ffff828c8014d03f>] send_mmio_req+0x14f/0x1b0
(XEN)    [<ffff828c8014e568>] mmio_operands+0xa8/0x160
(XEN)    [<ffff828c8014eb96>] handle_mmio+0x576/0x880
(XEN)    [<ffff828c801632b2>] vmx_vmexit_handler+0x1832/0x1900


I'm now trying ot figure out the IP that causes vm exit so I can figure where 
in the guest/guest-driver its writing to the APIC.
On the guest side, I see that evtchn_pending_sel is not set in 
evtchn_interrupt().

Any ideas/suggestions would be great as it is a critical bug.

Thanks
Mukesh