From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: possible use-after-free in 2.5.44 scsi changes Date: Thu, 31 Oct 2002 15:46:53 +0100 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <20021031144653.GE6549@suse.de> References: <20021031131824.GA6549@suse.de> <20021031144103.103D286E73@primary.mx.nitric.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20021031144103.103D286E73@primary.mx.nitric.com> List-Id: linux-scsi@vger.kernel.org To: merlin Cc: Badari Pulavarty , linux-scsi@vger.kernel.org On Thu, Oct 31 2002, merlin wrote: > r/axboe@suse.de/2002.10.31/14:18:24 > >On Wed, Oct 30 2002, merlin wrote: > >> Hi Badari, > >> > >> I grabbed 2.5.45 and added the printks you describe.. The kernel > >> dies before the syslog is written and I don't have a serial device > >> to try capturing the output there, but this is what I scribbled > >> down: > >> > >> ...lots of stuff ... > >> home: clean > >> made a new seg: 1 (c18adc70, 4096, 0) > >> Loop: brvprv: c18adc70 bvec:c18ad838 offset:0 length:4096 > >> made a new seg: 2 (c18ad838, 4096, 0) > >> returning segs: 2 > >> Incorrect number of segments after building list > >> counted 2, received 1 > >> ...some stuff... > >> > >> Things went on for a few more messages before the kernel died > >> a death. > >> > >> It's an SMP box so the seg stuff that precedes the error may > >> be unrelated; I don't have a good enough grasp to be sure. I > >> guess an interesting value to know might be max_segment_size. > >> > >> Half tempted to try a non-SMP build, just to see. Each time I > >> do this, I get a bit more (recoverable) fs damage, but still.. > > > >SMP should not make a difference. Does this patch make a difference? > > Same error I'm afraid; ``Incorrect number of segments after building list > counted 2, received 1'' follows shortly by kernel panic.. in drivers/scsi/aic7xxx/aic7xxx_linux_host.h:83, change ENABLE_CLUSTERING to DISABLE_CLUSTERING and repeat the test, please. -- Jens Axboe