Re: zpool export: umount failed, device inexplicably busy

From: Ryan Moeller <freqlabs_at_FreeBSD.org>
Date: Mon, 30 Nov 2020 06:09:34 -0500
On 10/6/20 4:29 PM, Graham Perrin wrote:
> lsof finds no open file.


Please be wary of lsof. I'm not sure it works on OpenZFS. The port 
reaches into /usr/src for zfs headers in locations that don't exist 
anymore to access kernel memory in /dev/kmem using structs that are 
different in OpenZFS. It is likely not building the ZFS support code on 
13-current, and it is not expected to work on 12 with openzfs from 
ports, either.

-Ryan


>
> How else might I tell why the device is busy?
>
> Mobile hard disk drive, USB.
>
> -- 
>
> root_at_momh167-gjp4-8570p:~ # zpool export Transcend
> cannot unmount '/Volumes/t500': umount failed
> root_at_momh167-gjp4-8570p:~ # lsof /Volumes/t500
> root_at_momh167-gjp4-8570p:~ # zpool export Transcend
> cannot unmount '/Volumes/t500': umount failed
> root_at_momh167-gjp4-8570p:~ # zpool export Transcend
> cannot unmount '/Volumes/t500': umount failed
> root_at_momh167-gjp4-8570p:~ # umount /Volumes/t500/
> umount: unmount of /Volumes/t500 failed: Device busy
> root_at_momh167-gjp4-8570p:~ # lsof /Volumes/t500
> root_at_momh167-gjp4-8570p:~ # zfs version
> zfs-0.8.0-1
> zfs-kmod-0.8.0-1
> root_at_momh167-gjp4-8570p:~ # zpool iostat Transcend 3
>               capacity     operations     bandwidth
> pool        alloc   free   read  write   read  write
> ----------  -----  -----  -----  -----  -----  -----
> Transcend    126G   338G      0      0  3.29K  1.45K
> Transcend    126G   338G      0      0      0      0
> Transcend    126G   338G      0      0      0      0
> Transcend    126G   338G      0      0      0      0
> Transcend    126G   338G      0      0      0      0
> Transcend    126G   338G      0      0      0      0
> ^C
> root_at_momh167-gjp4-8570p:~ # umount /Volumes/t500/
> umount: unmount of /Volumes/t500 failed: Device busy
> root_at_momh167-gjp4-8570p:~ # ls -ahl /Volumes/t500
> total 10
> drwxr-xr-x  3 root          wheel            3B Sep  2 19:02 .
> drwxr-xr-x  4 root          wheel            4B Sep  5 09:15 ..
> drwxr-xr-x  6 grahamperrin  grahamperrin     6B Sep 11 17:54 VirtualBox
> root_at_momh167-gjp4-8570p:~ # zpool status Transcend
>   pool: Transcend
>  state: ONLINE
>   scan: scrub repaired 0B in 00:28:07 with 0 errors on Tue Oct  6 
> 00:03:13 2020
> config:
>
>         NAME        STATE     READ WRITE CKSUM
>         Transcend   ONLINE       0     0     0
>           da0p1     ONLINE       0     0     0
>
> errors: No known data errors
> root_at_momh167-gjp4-8570p:~ # umount /Volumes/t500/
> umount: unmount of /Volumes/t500 failed: Device busy
> root_at_momh167-gjp4-8570p:~ # lsof /Volumes/t500
> root_at_momh167-gjp4-8570p:~ # date ; uname -v
> Tue Oct  6 21:20:17 BST 2020
> FreeBSD 13.0-CURRENT #67 r366424: Sun Oct  4 19:54:32 BST 2020 
> root_at_momh167-gjp4-8570p:/usr/obj/usr/src/amd64.amd64/sys/GENERIC-NODEBUG
> root_at_momh167-gjp4-8570p:~ # ls /dev/da*
> /dev/da0        /dev/da0p1
> root_at_momh167-gjp4-8570p:~ # zfs get all Transcend Transcend/VirtualBox
> NAME                  PROPERTY VALUE                     SOURCE
> Transcend             type filesystem                -
> Transcend             creation              Wed Sep  2 18:31 2020     -
> Transcend             used 126G                      -
> Transcend             available 324G                      -
> Transcend             referenced 126G                      -
> Transcend             compressratio 1.66x                     -
> Transcend             mounted yes                       -
> Transcend             quota none                      default
> Transcend             reservation none default
> Transcend             recordsize 128K                      default
> Transcend             mountpoint /Volumes/t500             local
> Transcend             sharenfs off                       default
> Transcend             checksum on                        default
> Transcend             compression zstd                      local
> Transcend             atime on                        default
> Transcend             devices on                        default
> Transcend             exec on                        default
> Transcend             setuid on                        default
> Transcend             readonly off                       default
> Transcend             jailed off                       default
> Transcend             snapdir hidden                    default
> Transcend             aclmode discard                   default
> Transcend             aclinherit restricted                default
> Transcend             createtxg 1                         -
> Transcend             canmount on                        default
> Transcend             xattr on                        default
> Transcend             copies 1                         default
> Transcend             version 5                         -
> Transcend             utf8only off                       -
> Transcend             normalization none                      -
> Transcend             casesensitivity sensitive                 -
> Transcend             vscan off                       default
> Transcend             nbmand off                       default
> Transcend             sharesmb off                       default
> Transcend             refquota none                      default
> Transcend             refreservation none default
> Transcend             guid 6806553549477274436       -
> Transcend             primarycache all default
> Transcend             secondarycache all default
> Transcend             usedbysnapshots 0B                        -
> Transcend             usedbydataset 126G                      -
> Transcend             usedbychildren 47.2M                     -
> Transcend             usedbyrefreservation 0B                        -
> Transcend             logbias latency                   default
> Transcend             objsetid 54                        -
> Transcend             dedup off                       default
> Transcend             mlslabel none                      default
> Transcend             sync standard                  default
> Transcend             dnodesize legacy                    default
> Transcend             refcompressratio 1.66x                     -
> Transcend             written 126G                      -
> Transcend             logicalused 210G                      -
> Transcend             logicalreferenced 210G -
> Transcend             volmode default                   default
> Transcend             filesystem_limit none default
> Transcend             snapshot_limit none default
> Transcend             filesystem_count none default
> Transcend             snapshot_count none default
> Transcend             snapdev hidden                    default
> Transcend             context none                      default
> Transcend             fscontext none                      default
> Transcend             defcontext none                      default
> Transcend             rootcontext none default
> Transcend             relatime off                       default
> Transcend             redundant_metadata all default
> Transcend             overlay on                        default
> Transcend             encryption off                       default
> Transcend             keylocation none default
> Transcend             keyformat none                      default
> Transcend             pbkdf2iters 0 default
> Transcend             special_small_blocks 0                         
> default
> Transcend/VirtualBox  type filesystem                -
> Transcend/VirtualBox  creation              Wed Sep  2 19:02 2020     -
> Transcend/VirtualBox  used 200K                      -
> Transcend/VirtualBox  available 324G                      -
> Transcend/VirtualBox  referenced 200K                      -
> Transcend/VirtualBox  compressratio 1.00x                     -
> Transcend/VirtualBox  mounted no                        -
> Transcend/VirtualBox  quota none                      default
> Transcend/VirtualBox  reservation none default
> Transcend/VirtualBox  recordsize 128K                      default
> Transcend/VirtualBox  mountpoint /Volumes/t500/VirtualBox inherited 
> from Transcend
> Transcend/VirtualBox  sharenfs off                       default
> Transcend/VirtualBox  checksum on                        default
> Transcend/VirtualBox  compression zstd inherited from Transcend
> Transcend/VirtualBox  atime off                       local
> Transcend/VirtualBox  devices on                        default
> Transcend/VirtualBox  exec on                        default
> Transcend/VirtualBox  setuid on                        default
> Transcend/VirtualBox  readonly off                       default
> Transcend/VirtualBox  jailed off                       default
> Transcend/VirtualBox  snapdir hidden                    default
> Transcend/VirtualBox  aclmode discard                   default
> Transcend/VirtualBox  aclinherit restricted                default
> Transcend/VirtualBox  createtxg 375                       -
> Transcend/VirtualBox  canmount on                        default
> Transcend/VirtualBox  xattr on                        default
> Transcend/VirtualBox  copies 1                         default
> Transcend/VirtualBox  version 5                         -
> Transcend/VirtualBox  utf8only off                       -
> Transcend/VirtualBox  normalization none                      -
> Transcend/VirtualBox  casesensitivity sensitive                 -
> Transcend/VirtualBox  vscan off                       default
> Transcend/VirtualBox  nbmand off                       default
> Transcend/VirtualBox  sharesmb off                       default
> Transcend/VirtualBox  refquota none                      default
> Transcend/VirtualBox  refreservation none default
> Transcend/VirtualBox  guid 11240822048258000557      -
> Transcend/VirtualBox  primarycache all default
> Transcend/VirtualBox  secondarycache all default
> Transcend/VirtualBox  usedbysnapshots 0B                        -
> Transcend/VirtualBox  usedbydataset 200K                      -
> Transcend/VirtualBox  usedbychildren 0B                        -
> Transcend/VirtualBox  usedbyrefreservation 0B                        -
> Transcend/VirtualBox  logbias latency                   default
> Transcend/VirtualBox  objsetid 76                        -
> Transcend/VirtualBox  dedup off                       default
> Transcend/VirtualBox  mlslabel none                      default
> Transcend/VirtualBox  sync standard                  default
> Transcend/VirtualBox  dnodesize legacy                    default
> Transcend/VirtualBox  refcompressratio 1.00x                     -
> Transcend/VirtualBox  written 200K                      -
> Transcend/VirtualBox  logicalused 49.5K                     -
> Transcend/VirtualBox  logicalreferenced 49.5K -
> Transcend/VirtualBox  volmode default                   default
> Transcend/VirtualBox  filesystem_limit none default
> Transcend/VirtualBox  snapshot_limit none default
> Transcend/VirtualBox  filesystem_count none default
> Transcend/VirtualBox  snapshot_count none default
> Transcend/VirtualBox  snapdev hidden                    default
> Transcend/VirtualBox  context none                      default
> Transcend/VirtualBox  fscontext none                      default
> Transcend/VirtualBox  defcontext none                      default
> Transcend/VirtualBox  rootcontext none default
> Transcend/VirtualBox  relatime off                       default
> Transcend/VirtualBox  redundant_metadata all default
> Transcend/VirtualBox  overlay on                        default
> Transcend/VirtualBox  encryption aes-256-gcm               -
> Transcend/VirtualBox  keylocation prompt                    local
> Transcend/VirtualBox  keyformat passphrase                -
> Transcend/VirtualBox  pbkdf2iters 350000                    -
> Transcend/VirtualBox  encryptionroot Transcend/VirtualBox      -
> Transcend/VirtualBox  keystatus unavailable               -
> Transcend/VirtualBox  special_small_blocks 0                         
> default
> root_at_momh167-gjp4-8570p:~ # zpool get all Transcend
> NAME       PROPERTY VALUE                          SOURCE
> Transcend  size 464G                           -
> Transcend  capacity 27%                            -
> Transcend  altroot -                              default
> Transcend  health ONLINE                         -
> Transcend  guid 8076233369858608335            -
> Transcend  version -                              default
> Transcend  bootfs -                              default
> Transcend  delegation on                             default
> Transcend  autoreplace off                            default
> Transcend  cachefile -                              default
> Transcend  failmode wait                           default
> Transcend  listsnapshots off                            default
> Transcend  autoexpand off                            default
> Transcend  dedupratio 1.00x                          -
> Transcend  free 338G                           -
> Transcend  allocated 126G                           -
> Transcend  readonly off                            -
> Transcend  ashift 0                              default
> Transcend  comment -                              default
> Transcend  expandsize -                              -
> Transcend  freeing 0                              -
> Transcend  fragmentation 12%                            -
> Transcend  leaked 0                              -
> Transcend  multihost off                            default
> Transcend  checkpoint -                              -
> Transcend  load_guid 15610592478404149099           -
> Transcend  autotrim off                            default
> Transcend  feature_at_async_destroy enabled local
> Transcend  feature_at_empty_bpobj active local
> Transcend  feature_at_lz4_compress active local
> Transcend  feature_at_multi_vdev_crash_dump 
> enabled                        local
> Transcend  feature_at_spacemap_histogram active                         
> local
> Transcend  feature_at_enabled_txg active local
> Transcend  feature_at_hole_birth active                         local
> Transcend  feature_at_extensible_dataset active                         
> local
> Transcend  feature_at_embedded_data active local
> Transcend  feature_at_bookmarks enabled                        local
> Transcend  feature_at_filesystem_limits enabled                        local
> Transcend  feature_at_large_blocks enabled local
> Transcend  feature_at_large_dnode enabled local
> Transcend  feature_at_sha512 enabled                        local
> Transcend  feature_at_skein enabled                        local
> Transcend  feature_at_userobj_accounting active                         
> local
> Transcend  feature_at_encryption active                         local
> Transcend  feature_at_project_quota active local
> Transcend  feature_at_device_removal enabled local
> Transcend  feature_at_obsolete_counts enabled local
> Transcend  feature_at_zpool_checkpoint enabled local
> Transcend  feature_at_spacemap_v2 active local
> Transcend  feature_at_allocation_classes enabled                        
> local
> Transcend  feature_at_resilver_defer enabled local
> Transcend  feature_at_bookmark_v2 enabled local
> Transcend  feature_at_redaction_bookmarks enabled                        
> local
> Transcend  feature_at_redacted_datasets enabled                        local
> Transcend  feature_at_bookmark_written enabled local
> Transcend  feature_at_log_spacemap active local
> Transcend  feature_at_livelist enabled                        local
> Transcend  feature_at_device_rebuild enabled local
> Transcend  feature_at_zstd_compress active local
> root_at_momh167-gjp4-8570p:~ #
>
>
> _______________________________________________
> freebsd-current_at_freebsd.org mailing list
> https://lists.freebsd.org/mailman/listinfo/freebsd-current
> To unsubscribe, send any mail to 
> "freebsd-current-unsubscribe_at_freebsd.org"
Received on Mon Nov 30 2020 - 10:09:36 UTC

This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:41:26 UTC