Re: Re: [RFC] hw/nvme: Use irqfd to send interrupts

[樊金昊]

> In this version I left irqfd initialization to the first assertion of an
> irq. But I think it is better to initialize irqfd at cq creation time so we
> won’t bother checking it at each irq assertion. However if I put these code
> in nvme_init_cq(), irqfd does not work properly. After adding some
> tracepoints I found the MSI messages in MSI-X table changed after
> nvme_init_cq(). Specifically, the `data` field does not seem correct at the
> time when nvme_init_cq() is called.

I found that in Linux NVMe driver, in nvme_create_cq() 
(drivers/nvme/host/pci.c),
queue_request_irq() is called after nvme_init_queue(). Does this possibly
cause the incorrect MSI messages at CQ creation time?