ZFS on Linux: cannot destroy snapshot, dataset is busy

I’m trying to delete a bunch of old ZFS snapshots but I get errors saying that the datasets are busy:

[root@pool-01 ~]# zfs list -t snapshot -o name -S creation | grep ^pool/nfs/public/mydir | xargs -n 1 zfs destroy -vr
will destroy pool/nfs/public/mydir@autosnap_2019-02-24_03:13:17_hourly
will reclaim 408M
cannot destroy snapshot pool/nfs/public/mydir@autosnap_2019-02-24_03:13:17_hourly: dataset is busy
will destroy pool/nfs/public/mydir@autosnap_2019-02-24_02:13:17_hourly
will reclaim 409M
 cannot destroy snapshot pool/nfs/public/mydir@autosnap_2019-02-24_02:13:17_hourly: dataset is busy
will destroy pool/nfs/public/mydir@autosnap_2019-02-24_01:13:18_hourly will reclaim 394M

Running lsof shows no processes accessing these snapshots:

[root@pool-01 ~]# lsof | grep pool/nfs/public/mydir

There also appears to be no holds on any of the snapshots:

[root@pool-01 ~]# zfs holds pool/nfs/public/mydir@autosnap_2019-02-24_03:13:17_hourly
NAME                                                              TAG  TIMESTAMP

Is there anything else I should look out for? Anything else I can do besides a reoot?