Blog/Btrfs-progs v6.6.2

From Forza's ramblings

Btrfs-progs v6.6.2[edit | edit source]

Cropped image with saturn and its rings against black space
Saturn eclipsing the sun, seen from behind from the Cassini orbiter. The image is a composite assembled from images taken by the Cassini spacecraft on 15 September, 2006.

Btrfs-progs v6.6.2 was released. Please don't use version 6.6 as it has a bug that can prevent multi-device filesystems from being mounted.

Official releases are available from and


  • squota: change key number of EXTENT_OWNER_REF_KEY, sync with kernel 6.7-rc1
  • property set/get: completely skip char devices, trying to set properties and open /dev/watchdog* causes a reboot
  • other: build warnings, test updates, documentation updates

Changes in v6.6 since 6.5.3:

  • fix device scanning ioctl definition, accidental change to the 'forget' ioctl that breaks mounting multi-device filesystems
  • new global option --dry-run, now implemented for 'subvolume delete'
  • fi defrag: new option --step to defragment files in steps, report progress
  • balance: removed support for obsolete short syntax 'btrfs balance /path'
  • mkfs: print zone count for each device in the overview
  • check:
    • verify inline ref ordering
    • deprecate --clear-space-cache, moved to the 'rescue' group
  • rescue clear-space-cache: new command moved from 'btrfs check' implementing the same as option --clear-space-cache (to be deprecated and removed in the future)
  • dump-tree: output sequence number for inline refs
  • fixes:
    • fi resize: fallback to lowest devid when 1 does not exist, previously the command would fail with "No such device"
    • fi usage: fix "devices 0 != 1" message and broken output on multi-device filesystem
    • open files in non-blocking mode when reading fsid, this could hang when trying to open fifo files or some special character devices, was observed with 'prop set/get'
  • experimental:
    • mkfs: parametric zone size for emulated zoned mode
  • other:
    • cleanups refactoring
    • new and updated tests
    • CI updates
    • documentation updates

Static builds for aarch64 and x86_64[edit | edit source]

As usual there are static builds for ARM64/aarch64 and AMD64/x86_64 available at

For more information about static builds, check out the dedicate wiki page Btrfs/Statically_built_btrfs-progs