RE: [PATCH 3/7] vfio: Introduce interface to flush virqfd inject workqueue

[Tian, Kevin]

> From: Alex Williamson <alex.williamson@xxxxxxxxxx>
> Sent: Thursday, March 7, 2024 5:15 AM
> 
> In order to synchronize changes that can affect the thread callback,
> introduce an interface to force a flush of the inject workqueue.  The
> irqfd pointer is only valid under spinlock, but the workqueue cannot
> be flushed under spinlock.  Therefore the flush work for the irqfd is
> queued under spinlock.  The vfio_irqfd_cleanup_wq workqueue is re-used
> for queuing this work such that flushing the workqueue is also ordered
> relative to shutdown.
> 
> Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>

Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>