From: Jan Kara Subject: Re: Weird I/O errors with USB hard drive not remounting filesystem readonly Date: Tue, 24 Nov 2009 21:39:44 +0100 Message-ID: <20091124203944.GD16662@quack.suse.cz> References: <20091124195607.GC16662@quack.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Jan Kara , Boaz Harrosh , tmhikaru@gmail.com, Kernel development list , USB list , Jens Axboe , SCSI development list , linux-ext4@vger.kernel.org To: Alan Stern Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Tue 24-11-09 15:13:01, Alan Stern wrote: > On Tue, 24 Nov 2009, Jan Kara wrote: > > > After digging in block layer code, it's as we suspected: > > In case of host error DID_ERROR (which is our case), scsi request is > > retried iff it is not a FAILFAST request which is set if bio is doing > > readahead... So this is explained and everything behaves as it should. > > Thanks everybody involved :). > > Okay, very good. There remains the question of the disturbing error > messages in the system log. Should they be supressed for FAILFAST > requests? I think it's useful they are there because ultimately, something really went wrong and you should better investigate. BTW, "end_request: I/O error" messages are in the log even for requests where we retried and succeeded... Honza