Xen disks need to be whitelisted as well.
ACTION=="change", SUBSYSTEM=="scsi", ENV{DEVTYPE}=="scsi_device", TEST=="block", ATTR{block/*/uevent}="change"
# watch metadata changes, caused by tools closing the device node which was opened for writing
-ACTION!="remove", SUBSYSTEM=="block", KERNEL=="loop*|nvme*|sd*|vd*", OPTIONS+="watch"
+ACTION!="remove", SUBSYSTEM=="block", KERNEL=="loop*|nvme*|sd*|vd*|xvd*", OPTIONS+="watch"
ACTION=="remove", GOTO="persistent_storage_end"
SUBSYSTEM!="block", GOTO="persistent_storage_end"
-KERNEL!="loop*|mmcblk*[0-9]|msblk*[0-9]|mspblk*[0-9]|nvme*|sd*|sr*|vd*|bcache*|xvd*", GOTO="persistent_storage_end"
+KERNEL!="loop*|mmcblk*[0-9]|msblk*[0-9]|mspblk*[0-9]|nvme*|sd*|sr*|vd*|xvd*|bcache*", GOTO="persistent_storage_end"
# ignore partitions that span the entire disk
TEST=="whole_disk", GOTO="persistent_storage_end"