Buffer cache mistake

[Taylor R Campbell <riastradh%NetBSD.org@localhost>]

This morning at 15:48 UTC, while aiming to add some dtrace probes to
the buffer cache (normally a totally innocuous change so I wasn't
paying very close attention), I committed a mistake that totally
screwed it up -- causing bbusy to return a result indicating success
even if it actually failed:

https://mail-index.NetBSD.org/source-changes/2020/02/20/msg114193.html

This can kinda badly screw up file systems (primarily metadata but
corruption in data too), so I recommend you update to the fix which I
committed as soon as I noticed this evening at 02:04 UTC:

https://mail-index.NetBSD.org/source-changes/2020/02/21/msg114202.html

Sorry!