no further I/O will be permitted and the status will just
contain the string 'Fail'. The userspace recovery tools
should then be used.
+needs_check : 'needs_check' if set, '-' if not set
+ A metadata operation has failed, resulting in the needs_check
+ flag being set in the metadata's superblock. The metadata
+ device must be deactivated and checked/repaired before the
+ cache can be made fully operational again. '-' indicates
+ needs_check is not set.
Messages
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