On Sat, Feb 17, 2024 at 08:08:48PM +0200, Parav Pandit wrote: > When the PCI device is surprise removed, requests won't complete from > the device. These IOs are never completed and disk deletion hangs > indefinitely. > > Fix it by aborting the IOs which the device will never complete > when the VQ is broken. > > With this fix now fio completes swiftly. > An alternative of IO timeout has been considered, however > when the driver knows about unresponsive block device, swiftly clearing > them enables users and upper layers to react quickly. > > Verified with multiple device unplug cycles with pending IOs in virtio > used ring and some pending with device. > > In future instead of VQ broken, a more elegant method can be used. At the > moment the patch is kept to its minimal changes given its urgency to fix > broken kernels. > > Fixes: 43bb40c5b926 ("virtio_pci: Support surprise removal of virtio pci device") > Cc: stable@xxxxxxxxxxxxxxx > Reported-by: lirongqing@xxxxxxxxx > Closes: https://lore.kernel.org/virtualization/c45dd68698cd47238c55fb73ca9b4741@xxxxxxxxx/ > Co-developed-by: Chaitanya Kulkarni <kch@xxxxxxxxxx> > Signed-off-by: Chaitanya Kulkarni <kch@xxxxxxxxxx> > Signed-off-by: Parav Pandit <parav@xxxxxxxxxx> > --- > drivers/block/virtio_blk.c | 54 ++++++++++++++++++++++++++++++++++++++ > 1 file changed, 54 insertions(+) > > diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c > index 2bf14a0e2815..59b49899b229 100644 > --- a/drivers/block/virtio_blk.c > +++ b/drivers/block/virtio_blk.c > @@ -1562,10 +1562,64 @@ static int virtblk_probe(struct virtio_device *vdev) > return err; > } > > +static bool virtblk_cancel_request(struct request *rq, void *data) > +{ > + struct virtblk_req *vbr = blk_mq_rq_to_pdu(rq); > + > + vbr->in_hdr.status = VIRTIO_BLK_S_IOERR; > + if (blk_mq_request_started(rq) && !blk_mq_request_completed(rq)) > + blk_mq_complete_request(rq); > + > + return true; > +} > + > +static void virtblk_cleanup_reqs(struct virtio_blk *vblk) > +{ > + struct virtio_blk_vq *blk_vq; > + struct request_queue *q; > + struct virtqueue *vq; > + unsigned long flags; > + int i; > + > + vq = vblk->vqs[0].vq; > + if (!virtqueue_is_broken(vq)) > + return; > + What if the surprise happens after the above check? Thanks, Ming