similar to: [PATCH 1/1] [virt] virtio-blk: Use ida to allocate disk index

Based on a patch by Mark Wu <dwu at redhat.com> Current index allocation in virtio-blk is based on a monotonically increasing variable "index". This means we'll run out of numbers after a while. It also could cause confusion about the disk name in the case of hot-plugging disks. Change virtio-blk to use ida to allocate index, instead. Signed-off-by: Michael S. Tsirkin

Based on a patch by Mark Wu <dwu at redhat.com> Current index allocation in virtio-blk is based on a monotonically increasing variable "index". This means we'll run out of numbers after a while. It also could cause confusion about the disk name in the case of hot-plugging disks. Change virtio-blk to use ida to allocate index, instead. Signed-off-by: Michael S. Tsirkin

A userspace process holding a file descriptor to a virtio_blk device can still invoke block_device_operations after hot unplug. For example, a program that has /dev/vdb open can call ioctl(HDIO_GETGEO) after hot unplug to invoke virtblk_getgeo(). Introduce a reference count in struct virtio_blk so that its lifetime covers both virtio_driver probe/remove and block_device_operations open/release

A userspace process holding a file descriptor to a virtio_blk device can still invoke block_device_operations after hot unplug. For example, a program that has /dev/vdb open can call ioctl(HDIO_GETGEO) after hot unplug to invoke virtblk_getgeo(). Introduce a reference count in struct virtio_blk so that its lifetime covers both virtio_driver probe/remove and block_device_operations open/release

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 use-after-free accessing vblk->vdev in virtblk_getgeo() when ioctl(HDIO_GETGEO) is invoked: BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 IP: [<ffffffffc00e5450>] virtio_check_driver_offered_feature+0x10/0x90

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 use-after-free accessing vblk->vdev in virtblk_getgeo() when ioctl(HDIO_GETGEO) is invoked: BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 IP: [<ffffffffc00e5450>] virtio_check_driver_offered_feature+0x10/0x90

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 use-after-free accessing vblk->vdev in virtblk_getgeo() when ioctl(HDIO_GETGEO) is invoked: BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 IP: [<ffffffffc00e5450>] virtio_check_driver_offered_feature+0x10/0x90

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 use-after-free accessing vblk->vdev in virtblk_getgeo() when ioctl(HDIO_GETGEO) is invoked: BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 IP: [<ffffffffc00e5450>] virtio_check_driver_offered_feature+0x10/0x90

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 Tue, Apr 28, 2020 at 11:25:07AM -0400, Michael S. Tsirkin wrote: > On Tue, Apr 28, 2020 at 03:30:09PM +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. For example, a > > program that has /dev/vdb open can call ioctl(HDIO_GETGEO) after hot > > unplug to

Hi, Jens & Rusty This version is rebased against linux-next which resolves the conflict with Paolo Bonzini's 'virtio-blk: allow toggling host cache between writeback and writethrough' patch. Patch 1/3 and 2/3 applies on linus's master as well. Since Rusty will pick up patch 3/3 so the changes to block core (adding blk_bio_map_sg()) will have a user. Jens, could you please

Hi, Jens & Rusty This version is rebased against linux-next which resolves the conflict with Paolo Bonzini's 'virtio-blk: allow toggling host cache between writeback and writethrough' patch. Patch 1/3 and 2/3 applies on linus's master as well. Since Rusty will pick up patch 3/3 so the changes to block core (adding blk_bio_map_sg()) will have a user. Jens, could you please

Hi, The following patches fix couple of memory leaks in the virtio and remoteproc cores when using these as modules, and going through a cycle of insmod and rmmod with at least a device registered with the corresponding cores in between. I ran into this on our downstream product kernels on both 3.14 and 4.1 based kernels, and should apply to the latest kernel as well. Patches can be picked up

Hi, The following patches fix couple of memory leaks in the virtio and remoteproc cores when using these as modules, and going through a cycle of insmod and rmmod with at least a device registered with the corresponding cores in between. I ran into this on our downstream product kernels on both 3.14 and 4.1 based kernels, and should apply to the latest kernel as well. Patches can be picked up

This patchset implements bio-based IO path for virito-blk to improve performance. Fio test shows it gives, 28%, 24%, 21%, 16% IOPS boost and 32%, 17%, 21%, 16% latency improvement for sequential read/write, random read/write respectively. Asias He (2): block: Add blk_bio_map_sg() helper virtio-blk: Add bio-based IO path for virtio-blk block/blk-merge.c | 63 ++++++++++++++

This patchset implements bio-based IO path for virito-blk to improve performance. Fio test shows it gives, 28%, 24%, 21%, 16% IOPS boost and 32%, 17%, 21%, 16% latency improvement for sequential read/write, random read/write respectively. Asias He (2): block: Add blk_bio_map_sg() helper virtio-blk: Add bio-based IO path for virtio-blk block/blk-merge.c | 63 ++++++++++++++

Hi folks, This version added REQ_FLUSH and REQ_FUA support as suggested by Christoph and rebased against latest linus's tree. Jens, could you please consider picking up the dependencies 1/4 and 2/4 in your tree. Thanks! This patchset implements bio-based IO path for virito-blk to improve performance. Fio test shows bio-based IO path gives the following performance improvement: 1) Ramdisk

Hi folks, This version added REQ_FLUSH and REQ_FUA support as suggested by Christoph and rebased against latest linus's tree. Jens, could you please consider picking up the dependencies 1/4 and 2/4 in your tree. Thanks! This patchset implements bio-based IO path for virito-blk to improve performance. Fio test shows bio-based IO path gives the following performance improvement: 1) Ramdisk

This patch series renames "sd_format_disk_name()" to "disk_name_format()" and moves it into block core. So that who needs formatting disk name can use it, instead of duplicating these similar help functions. Ren Mingxin (4): block: add function disk_name_format() into block core scsi: replace sd_format_disk_name() to disk_name_format() block: replace