Userspace listens to the KOBJ_ADD uevent generated in add_disk. At that point we haven't created the serial attribute file, therefore depending on how fast udev reacts, the /dev/disk/by-id/ entry doesn't always get created. This race condition can be easily reproduced by hot plugging a number of virtio-blk disks. Also in systemd, there used to be a related workaround in udev rules called 'WAIT_FOR="serial"', but it is removed in later versions. Now let's generate a KOBJ_CHANGE event after the attributes are ready. Signed-off-by: Fam Zheng <famz@xxxxxxxxxx> --- drivers/block/virtio_blk.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index f3a59f9..cd9a036 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -733,7 +733,7 @@ static int virtblk_probe(struct virtio_device *vdev) virtio_device_ready(vdev); - add_disk(vblk->disk, true); + add_disk(vblk->disk, false); err = device_create_file(disk_to_dev(vblk->disk), &dev_attr_serial); if (err) goto out_del_disk; @@ -746,6 +746,7 @@ static int virtblk_probe(struct virtio_device *vdev) &dev_attr_cache_type_ro); if (err) goto out_del_disk; + disk_gen_uevents(vblk->disk); return 0; out_del_disk: -- 2.9.0 _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
