From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Subject: Re: [Bug #14894] pohmelfs: NULL pointer dereference Date: Tue, 2 Feb 2010 13:18:09 -0800 Message-ID: <20100202211809.GB8755@kroah.com> References: <20091229163512.GA4958@ioremap.net> <200912292237.54182.rjw@sisk.pl> <20091230091433.GU4489@kernel.dk> <20100202205743.GA26703@ioremap.net> Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: <20100202205743.GA26703-i6C2adt8DTjR7s880joybQ@public.gmane.org> Sender: kernel-testers-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Evgeniy Polyakov Cc: Jens Axboe , "Rafael J. Wysocki" , Linux Kernel Mailing List , Kernel Testers List , Alexander Beregalov On Tue, Feb 02, 2010 at 11:57:43PM +0300, Evgeniy Polyakov wrote: > Hi. > > Sorry, it took really long to catch all the things around, but it is > better than never. > > History says that commit which introduced per-bdi writeback broke > pohmelfs, since it does not have backing store device and did not fill > appropriate superblock entry, which lead to crash on umoount. > > Jens provided a patch below, which I tested to fix the problem. > There is a problem though, when all writes happend before umount, > but did net yet written back to storage, get lost. I can not say whether > this happens because of per-bdi writeback (it should not I think), but > that's what happens. > > Albeit being a bug, it will not be fixed :) > The reason is simple, new backing storage for POHMELFS (a distributed > hash table called elliptics network) is essentially ready and I start > working on porting POHMELFS to it, which means all its bugs will be > fixed there^W^Werased and written from scratch. > > Jens, thanks a lot for you patch, Greg please pull it up. > If you did not find it or can not extract from the reply, I will resend. Please resend it with a signed-off-by line so that I can apply it. thanks, greg k-h