root on ZFS: Pool 'zroot' has encountered an uncorrectable I/O failure and has been suspended

From: Mark Millard via freebsd-arm <freebsd-arm_at_freebsd.org>
Date: Sun, 11 Jul 2021 03:02:02 UTC
I booted a Samsung PSSD T7 Touch that has a root on
ZFS confirugration on a MACCHIATObin Double Shot.
While I did not actively have it doing anything
beyond normal background processing it got:

(da0:umass-sim0:0:0:0): WRITE(10). CDB: 2a 00 4e 08 e7 f0 00 00 08 00 
(da0:umass-sim0:0:0:0): CAM status: CCB request completed with an error
(da0:umass-sim0:0:0:0): Retrying command, 3 more tries remain
ugen2.2: <Samsung PSSD T7 Touch> at usbus2 (disconnected)
umass0: at uhub1, port 1, addr 1 (disconnected)
(da0:umass-sim0:0:0:0): WRITE(10). CDB: 2a 00 4e 08 e7 f0 00 00 08 00 
(da0:umass-sim0:0:0:0): CAM status: CCB request completed with an error
(da0:umass-sim0:0:0:0): Retrying command, 2 more tries remain
da0 at umass-sim0 bus 0 scbus4 target 0 lun 0
da0: <Samsung PSSD T7 Touch 0>  s/n REPLACED detached
Solaris: WARNING: Pool 'zroot' has encountered an uncorrectable I/O failure and has been suspended.

Its a root on ZFS context. That leads to things locking
up the next time it tries an access, such as my stupid
attempt at "zpool list".

Looks like a context where a forced power-off is the
way it has to be handled.

For reference, after rebooting (but on an RPi4B 8GiByte):

# zpool status
  pool: zroot
 state: ONLINE
  scan: scrub repaired 0B in 00:16:01 with 0 errors on Sat Jul 10 19:38:59 2021
config:

        NAME        STATE     READ WRITE CKSUM
        zroot       ONLINE       0     0     0
          da0p4     ONLINE       0     0     0

errors: No known data errors


Note: I'm using zfs primarily for bectl, not other properties
zfs is biased toward.

===
Mark Millard
marklmi at yahoo.com
( dsl-only.net went
away in early 2018-Mar)