From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH] direct-io: Fix negative return from dio read beyond eof To: Greg KH References: <1447964734-16010-1-git-send-email-jack@suse.cz> <56A89E16.3060706@scylladb.com> <20160127171302.GA2943@kroah.com> Cc: Jan Kara , axboe@kernel.dk, linux-fsdevel@vger.kernel.org, Jeff Moyer , stable@vger.kernel.org, Steven Whitehouse From: Avi Kivity Message-ID: <56A8FB70.6040803@scylladb.com> Date: Wed, 27 Jan 2016 19:16:32 +0200 MIME-Version: 1.0 In-Reply-To: <20160127171302.GA2943@kroah.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: stable-owner@vger.kernel.org List-ID: On 01/27/2016 07:13 PM, Greg KH wrote: > On Wed, Jan 27, 2016 at 12:38:14PM +0200, Avi Kivity wrote: >> On 11/19/2015 10:25 PM, Jan Kara wrote: >>> Assume a filesystem with 4KB blocks. When a file has size 1000 bytes and >>> we issue direct IO read at offset 1024, blockdev_direct_IO() reads the >>> tail of the last block and the logic for handling short DIO reads in >>> dio_complete() results in a return value -24 (1000 - 1024) which >>> obviously confuses userspace. >>> >>> Fix the problem by bailing out early once we sample i_size and can >>> reliably check that direct IO read starts beyond i_size. >>> >>> Reported-by: Avi Kivity >>> Fixes: 9fe55eea7e4b444bafc42fa0000cc2d1d2847275 >>> CC: stable@vger.kernel.org >> While this patch made it into upstream, it did not appear in 4.3.4. Did it >> slip through the proverbial cracks? Can it be queued for 4.3.5? > There are over 400 patches right now in my queue that haven't made it > into a 4.3.x kernel. Many projects would consider 400 patches a major release, and here they are behind two dots... > These are in the queue, in good company :) > > I'll go dig these out as I guess people care about them more than > others... > > Much appreciated.