# OpenZFS zfs-2.4.4

- Product: OpenZFS (https://whatsnew.fyi/product/openzfs)
- Vendor: OpenZFS
- Date: 2026-08-21
- Version: zfs-2.4.4
- Original notes: https://github.com/openzfs/zfs/releases/tag/zfs-2.4.4
- Permalink: https://whatsnew.fyi/product/openzfs/releases/zfs-2.4.4
- Labels: Platforms: Linux

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **added** — Add 'capsh' to commands.cfg
- **added** — Add zhack mmp reclaim command to recover a pool stranded by MMP
- **added** — Implement VERIFY_IMPLY and VERIFY_EQUIV in libspl
- **added** — Add SECURITY.md policy file
- **changed** — Use calling credential to check for device access in vdev_disk
- **changed** — Use calling credential to check for device access in vdev_file
- **changed** — Add credential argument to zfs_file_open and use it to check access
- **changed** — Pass credential to vdev_open to check for permission to open device
- **changed** — Detect idmap method via generic_permission test
- **changed** — Make systemd-udev-settle optional for the import units
- **changed** — Improve native handling of unterminated strings in nvpair
- **changed** — Handle differences in how to flush delay workqueue for Linux 5.19 and 6.17
- **changed** — Follow follow_down() gains flags arg for Linux 6.3
- **changed** — Handle vfs_parse_fs_string() taking 3 args for Linux 6.18 compatibility
- **changed** — Update supported FreeBSD release to 15.1
- **fixed** — Fix negative time overflows in DDT pruning
- **fixed** — Tell a failed uberblock claim apart from remote activity in mmp
- **fixed** — Fix operator precedence in nvpair
- **fixed** — Fix release detection when build dir is not source dir
- **fixed** — Fix zvol_request_sync documentation regarding blk-mq

###### Supported Platforms
- **Linux**: compatible with 4.18 - 7.2 kernels
- **FreeBSD**: compatible with releases starting from 13.3+, 14.0+

###### Changes
- [zfs-2.4.4] Add 'capsh' to commands.cfg
- ZTS: device access tests #18960
- vdev_disk: use calling cred to check for device access #18960
- vdev_file: use calling cred to check for device access #18960
- zfs_file_open: add cred arg, use it to check access #18960
- vdev_open: pass credential to check for permission to open device #18960
- secpolicy_zfs: add a note about the power of CAP_SYS_ADMIN #18959
- secpolicy_sys_config: only permit a global zone credential #18959
- secpolicy_zinject: only permit a global zone credential #18959
- secpolicy_nfs: remove, not used #18959
- ZTS: test secpolicy_zinject correctly limits namespace access #18959
- ZTS: test secpolicy_sys_config correctly limits namespace access #18959
- config: detect idmap method via generic_permission test #18769
- mmp: tell a failed uberblock claim apart from remote activity #18892
- ZTS: add coverage for zhack mmp reclaim #18892
- zhack: add "mmp reclaim" to recover a pool stranded by MMP #18892
- Make systemd-udev-settle optional for the import units #18832
- Linux 7.2 compat: META #18941
- Fix negative time overflows in DDT pruning #18886
- nvpair: i_get_value_size() string array handling tweak #18877
- nvpair: Improve native handling of unterminated strings #18876
- CodeQL: Flag implicit compare-then-assign in branch conditions #18899
- Linux 5.19/6.17: handle differences in how to flush delay workqueue #18847
- Linux 6.3: follow_down() gains flags arg #18847
- Linux 6.18 compat: vfs_parse_fs_string() takes 3 args #18847
- nvpair: Fix operator precedence #18874
- ZTS: don't read a command's exit status as a missing binary #18726 #18882
- build: Fix release detection when build dir is not source dir #18891
- CI: don't fail a passing job when a log reader has already exited #18885
- CI: publish the per-VM test counter atomically #18885
- man: zvol_request_sync is not ignored under blk-mq #18887
- libzfs: don't read a dataset handle after closing it in resume send #18870 #18883
- ZTS: add coverage for the MMP claim on a degraded mirror #18855
- mmp: do not require writes to mirror legs the config marks absent #18855
- libzfs: String trimming should not operate out of bounds #18868
- libzfs: don't truncate a resolved vdev path in zpool_vdev_name() #18851 #18871
- libzfs: Do not call munmap() when mmap() fails #18869
- Add missing checks to zfs_clone_range_replay() #18867
- Fix DMU bonus hold leak on I/O error #18865
- zfs: fix stale POSIX ACL cache after rollback #18837
- zed: let autoexpand see capacity changes on partitioned disks #12505 #18833
- zpool export: return EBUSY when zvol minors are in use #18841
- ZTS: make file_check actually compare the resume test results #18834
- ZTS: save ZAP_MICRO_MAX_SIZE before the large microzap tests change it #18834
- dmu_recv: Avoid potential null deref #18848
- DDT: Fix several bugs in pruning #18838
- cstyle: better tolerance for struct literals
- libspl: Implement VERIFY_IMPLY and VERIFY_EQUIV #18822
- mmp: skip non-writeable vdevs during activity check #18823 #18835
- zdb: output refcounts from verify_spacemap_refcounts() #18809
- L2ARC: bound the rebuild by the write hand on a first sweep #3114 #3400 #5583 #10224 #12779 #18827
- ZTS: make zpool_iostat_interval_all teardown deterministic #18273 #18776
- libzfs: fallback VDEV_UPATH to VDEV_PATH for non-DM devices #18439 #18802
- Fix reads for blocks freed after being cloned #18421 #18724
- Rate limit Direct I/O verify zevents #18795
- CI: Update Alpine Linux runner to 3.24.1 #18790
- Remove libuutil from the pull request template and fix headings #18791
- ZTS: fix zpool_initialize_multiple_pools suspend race #18777
- CI: Fix race caused by shared ctr file updates #18778
- zpl_inode: remove zpl_rename no-flags variants #18769
- ZTS: stop zpool_i

_[Truncated at 4000 characters — full notes: https://github.com/openzfs/zfs/releases/tag/zfs-2.4.4]_