Seems that this may be a long-standing bug in openzfs v5
https://github.com/openzfs/zfs/issues/6332
** Bug watch added: github.com/openzfs/zfs/issues #6332
https://github.com/openzfs/zfs/issues/6332
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Bugs, which is
I've just realised (newbie here :-)) that /var/log/apt/history.* has
information on package versions which may be useful.
Linux version before/after problem:
Start-Date: 2021-01-28 15:42:31
Commandline: apt-get dist-upgrade
Requested-By: ubuntu (1000)
Install: linux-image-5.4.0-1028-raspi:arm64
The date (Jan 29) of the first occurrence of the panic suggests that it
was not caused by changes in the packages
libnvpair1linux 0.8.3-1ubuntu12.6
libuutil1linux 0.8.3-1ubuntu12.6
libzfs2linux 0.8.3-1ubuntu12.6
libzpool2linux 0.8.3-1ubuntu12.6
zfs-zed
Going back through logfiles the first occurrence is
Jan 29 12:27:52 donny kernel: [72122.085286] PANIC at
zfs_vfsops.c:585:zfs_space_delta_cb()
So it seems to have started after I upgraded from Linux version
5.4.0-1026-raspi to 1028
Jan 27 04:27:18 donny kernel: [0.00] Linux version
Public bug reported:
When running rsync or tree (haven't tried much else) on much of the
filesystem it will pretty routinely throw a panic report in
syslog/kern.log, and the rsync/tree operation will later hang solidly
such that even ^C doesn't break back to the shell, and any further file
