similar to: [ 01/82] virtio-blk: Call del_gendisk() before disable guest kick

3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Asias He <asias at redhat.com> commit 02e2b124943648fba0a2ccee5c3656a5653e0151 upstream. del_gendisk() might not return due to failing to remove the /sys/block/vda/serial sysfs entry when another thread (udev) is trying to read it. virtblk_remove() vdev->config->reset() : guest

3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Asias He <asias at redhat.com> commit 02e2b124943648fba0a2ccee5c3656a5653e0151 upstream. del_gendisk() might not return due to failing to remove the /sys/block/vda/serial sysfs entry when another thread (udev) is trying to read it. virtblk_remove() vdev->config->reset() : guest

Deleting the disk and partitions in virtblk_remove() via del_gendisk() causes never ending waits when trying to synch dirty inode pages. A dummy virtqueue_notify() in virtblk_remove() is used to detect a host notification error, latter occurs when block device was hot-unplugged. When the dummy host kick failed blk_cleanup_queue() should be invoked prior to del_gendisk(). Signed-off-by: Heinz

Create a new attribute for virtio-blk devices that will fetch the serial number of the block device. This attribute can be used by udev to create disk/by-id symlinks for devices that don't have a UUID (filesystem) associated with them. ATA_IDENTIFY strings are special in that they can be up to 20 chars long and aren't required to be NULL-terminated. The buffer is also zero-padded

Create a new attribute for virtio-blk devices that will fetch the serial number of the block device. This attribute can be used by udev to create disk/by-id symlinks for devices that don't have a UUID (filesystem) associated with them. ATA_IDENTIFY strings are special in that they can be up to 20 chars long and aren't required to be NULL-terminated. The buffer is also zero-padded

If we reset the virtio-blk device before the requests already dispatched to the virtio-blk driver from the block layer are finised, we will stuck in blk_cleanup_queue() and the remove will fail. blk_cleanup_queue() calls blk_drain_queue() to drain all requests queued before DEAD marking. However it will never success if the device is already stopped. We'll have q->in_flight[] > 0, so

If we reset the virtio-blk device before the requests already dispatched to the virtio-blk driver from the block layer are finised, we will stuck in blk_cleanup_queue() and the remove will fail. blk_cleanup_queue() calls blk_drain_queue() to drain all requests queued before DEAD marking. However it will never success if the device is already stopped. We'll have q->in_flight[] > 0, so

This patch set fixes the race when hot-unplug stressed disk. Asias He (3): virtio-blk: Call del_gendisk() before disable guest kick virtio-blk: Reset device after blk_cleanup_queue() virtio-blk: Use block layer provided spinlock drivers/block/virtio_blk.c | 25 ++++++------------------- 1 file changed, 6 insertions(+), 19 deletions(-) -- 1.7.10.2

This patch set fixes the race when hot-unplug stressed disk. Asias He (3): virtio-blk: Call del_gendisk() before disable guest kick virtio-blk: Reset device after blk_cleanup_queue() virtio-blk: Use block layer provided spinlock drivers/block/virtio_blk.c | 25 ++++++------------------- 1 file changed, 6 insertions(+), 19 deletions(-) -- 1.7.10.2

Code is added to the remove callback to verify if a device was lost. In case of a device loss further request queueing should be prevented by setting appropriate queue flags prior to invoking del_gendisk(). Blocking of request queueing leads to appropriate I/O errors when data are tried to be synched. Trying to synch data to a lost block device doesn't make too much sense. If the current

When user hot-unplug a disk which is busy serving I/O, __blk_run_queue might be unable to drain all the requests. As a result, the blk_drain_queue() would loop forever and blk_cleanup_queue would not return. So hot-unplug will fail. This patch adds a callback in blk_drain_queue() for low lever driver to abort requests. Currently, this is useful for virtio-blk to do cleanup in hot-unplug. Cc:

When user hot-unplug a disk which is busy serving I/O, __blk_run_queue might be unable to drain all the requests. As a result, the blk_drain_queue() would loop forever and blk_cleanup_queue would not return. So hot-unplug will fail. This patch adds a callback in blk_drain_queue() for low lever driver to abort requests. Currently, this is useful for virtio-blk to do cleanup in hot-unplug. Cc:

3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Asias He <asias at redhat.com> commit 483001c765af6892b3fc3726576cb42f17d1d6b5 upstream. blk_cleanup_queue() will call blk_drian_queue() to drain all the requests before queue DEAD marking. If we reset the device before blk_cleanup_queue() the drain would fail. 1) if the queue is stopped

3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Asias He <asias at redhat.com> commit 483001c765af6892b3fc3726576cb42f17d1d6b5 upstream. blk_cleanup_queue() will call blk_drian_queue() to drain all the requests before queue DEAD marking. If we reset the device before blk_cleanup_queue() the drain would fail. 1) if the queue is stopped

If we reset the virtio-blk device before the requests already dispatched to the virtio-blk driver from the block layer are finised, we will stuck in blk_cleanup_queue() and the remove will fail. blk_cleanup_queue() calls blk_drain_queue() to drain all requests queued before DEAD marking. However it will never success if the device is already stopped. We'll have q->in_flight[] > 0, so

If we reset the virtio-blk device before the requests already dispatched to the virtio-blk driver from the block layer are finised, we will stuck in blk_cleanup_queue() and the remove will fail. blk_cleanup_queue() calls blk_drain_queue() to drain all requests queued before DEAD marking. However it will never success if the device is already stopped. We'll have q->in_flight[] > 0, so

On Thu, Apr 30, 2020 at 11:14:10AM +0100, Stefan Hajnoczi wrote: > On Thu, Apr 30, 2020 at 10:43:23AM +0200, Stefano Garzarella wrote: > > On Wed, Apr 29, 2020 at 05:53:45PM +0100, Stefan Hajnoczi wrote: > > > A userspace process holding a file descriptor to a virtio_blk device can > > > still invoke block_device_operations after hot unplug. This leads to a > >

If we reset the virtio-blk device before the requests already dispatched to the virtio-blk driver from the block layer are finised, we will stuck in blk_cleanup_queue() and the remove will fail. blk_cleanup_queue() calls blk_drain_queue() to drain all requests queued before DEAD marking. However it will never success if the device is already stopped. We'll have q->in_flight[] > 0, so

If we reset the virtio-blk device before the requests already dispatched to the virtio-blk driver from the block layer are finised, we will stuck in blk_cleanup_queue() and the remove will fail. blk_cleanup_queue() calls blk_drain_queue() to drain all requests queued before DEAD marking. However it will never success if the device is already stopped. We'll have q->in_flight[] > 0, so

On Fri, Jan 14, 2011 at 05:01:37PM +0100, Christoph Hellwig wrote: > Wire up the virtio_driver config_changed method to get notified about > config changes raised by the host. For now we just re-read the device > size to support online resizing of devices, but once we add more > attributes that might be changeable they could be added as well. > > Note that the config_changed