Date: Tue, 5 Apr 2011 15:24:25 +0200 From: Borja Marcos <borjam@sarenet.es> To: Andriy Gapon <avg@FreeBSD.org> Cc: freebsd-scsi@FreeBSD.org Subject: Re: propose: change some sense codes handling Message-ID: <4D0D7E78-2491-4D45-9DDE-58E360C6BA06@sarenet.es> In-Reply-To: <4D9B0DF7.8020104@FreeBSD.org> References: <4D9AF9B7.9030107@FreeBSD.org> <D10B0D62-E11E-445C-B9FA-DB4276F678B0@sarenet.es> <4D9B0DF7.8020104@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Apr 5, 2011, at 2:41 PM, Andriy Gapon wrote: >>> Align handling of this condition with the rest of the conditions in = the same >>> family: "Power on occurred", "SCSI bus reset occurred", "Bus device = reset >>> function occurred", etc. >>> I don't see this particular condition should be special. >>> Any insights and/or historical reasons? >>=20 >> I would be cautious with this. Of course if it happened with no = outstanding operations and data committed to media, it should be = harmless. But if you power cycle a hard disk with a dirty cache, some of = the data won't be committed to disk. If you just retry the operation and = otherwise ignore the message (which is equivalent to just logging and = retrying) you keep writing data to a possibly corrupted medium. It can = certainly led to further corruption and make the problem worse. >>=20 >> My opinion, of course ;) >=20 > Sure :) > But why would this particular sense code be so different from other = similar codes > that I quoted above. I forgot. Of course it's not harmelss at all. That's the problem of = being multi-tasking ;) Reset or power on could indicate that any configuration written to the = device (mode pages) have gone back to the default values as well. So, = even with no outstanding operations, I would treat it with caution. And again, if you power cycle a device from which you have filesystems = attached I find it safer to treat it as an I/O error, unmounting the = filesystems, checking, etc, etc. Borja.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4D0D7E78-2491-4D45-9DDE-58E360C6BA06>