在 2021/4/7 上午7:27, Dongli Zhang 写道:
This will answer your question that "Can it bypass the masking?".
For vhost-scsi, virtio-blk, virtio-scsi and virtio-net, to write to eventfd is
not able to bypass masking because masking is to unregister the eventfd. To
write to eventfd does not take effect.
However, it is possible to bypass masking for vhost-net because vhost-net
registered a specific masked_notifier eventfd in order to mask irq. To write to
original eventfd still takes effect.
We may leave the user to decide whether to write to 'masked_notifier' or
original 'guest_notifier' for vhost-net.
My fault here. To write to masked_notifier will always be masked:(
Only when there's no bug in the qemu.
If it is EventNotifier level, we will not care whether the EventNotifier is
masked or not. It just provides an interface to write to EventNotifier.
Yes.
To dump the MSI-x table for both virtio and vfio will help confirm if the vector
is masked.
That would be helpful as well. It's probably better to extend "info pci"
command.
Thanks
Thank you very much!
Dongli Zhang
