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    SubjectRe: [kvm-devel] [RFC] Deferred interrupt handling.
    > What if we will force the specific device to the end of the list. Once
    > IRQ_NONE was returned by the other devices, we will mask the irq,
    > forward the irq to the guest, issue a timer for 1msec. Motivation:
    > 1msec is long enough for the guest to ack the irq + host unmask the irq

    It makes no difference. The deadlock isn't fixable by timing hacks.
    Consider the following sequence


    Guest0 - blocked on I/O

    IRQ14 from your hardware
    Block IRQ14
    Sent to guest (guest is blocked)

    IRQ14 from hard disk
    Ignored (as blocked)

    Deadlock

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