From: Christoph Hellwig <hch@infradead.org>
To: Phillip Susi <phill@thesusis.net>
Cc: linux-ide@vger.kernel.org
Subject: Re: Drive reset as an EH strategy when write cache is enabled
Date: Wed, 2 Dec 2020 15:03:30 +0000 [thread overview]
Message-ID: <20201202150330.GA25031@infradead.org> (raw)
In-Reply-To: <87r1o9phgd.fsf@vps.thesusis.net>
On Tue, Dec 01, 2020 at 12:24:50PM -0500, Phillip Susi wrote:
> A while back I noticed lines in my syslog indicating that a FLUSH CACHE
> command timed out and the drive was hard reset to recover. That made me
> wonder if such a thing makes any sense as a valid EH strategy. Any
> previous writes that returned successfully but are still sitting in the
> drive's write cache will be silently invalidated by resetting the drive
> won't they? Then the FLUSH CACHE command is retried, and of course,
> succeeds because it is now a NOOP. Then fsync() returns and postfix
> thinks my new email has been committed to the disk, when in fact, it has
> not.
>
> Am I mistaken somewhere or is the kernel really doing the wrong thing
> here?
If the device drops the content of the volatile write on a reset we'll
have much problems than that..
next prev parent reply other threads:[~2020-12-02 15:04 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-01 17:24 Drive reset as an EH strategy when write cache is enabled Phillip Susi
2020-12-02 15:03 ` Christoph Hellwig [this message]
2020-12-02 15:55 ` Phillip Susi
2020-12-02 18:58 ` James Bottomley
2020-12-02 22:11 ` Phillip Susi
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