On Tue, 12 Nov 2024 20:58:21 +0800, Ming Lei wrote: > Commit 4ce6e2db00de ("virtio-blk: Ensure no requests in virtqueues before > deleting vqs.") replaces queue quiesce with queue freeze in virtio-blk's > PM callbacks. And the motivation is to drain inflight IOs before suspending. > > block layer's queue freeze looks very handy, but it is also easy to cause > deadlock, such as, any attempt to call into bio_queue_enter() may run into > deadlock if the queue is frozen in current context. There are all kinds > of ->suspend() called in suspend context, so keeping queue frozen in the > whole suspend context isn't one good idea. And Marek reported lockdep > warning[1] caused by virtio-blk's freeze queue in virtblk_freeze(). > > [...] Applied, thanks! [1/1] virtio-blk: don't keep queue frozen during system suspend commit: 7678abee0867e6b7fb89aa40f6e9f575f755fb37 Best regards, -- Jens Axboe