From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jan Beulich" Subject: Re: [PATCH] linux/blkfront: fixes for 'xm block-detach ... --force' Date: Mon, 01 Mar 2010 10:07:05 +0000 Message-ID: <4B8B9FD90200007800031D04@vpn.id2.novell.com> References: <4B5443BC020000780002A81E@vpn.id2.novell.com> <1267221034.30168.71.camel@agari.van.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <1267221034.30168.71.camel@agari.van.xensource.com> Content-Disposition: inline List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Daniel Stodden Cc: JeremyFitzhardinge , "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org >>> Daniel Stodden 26.02.10 22:50 >>> >I think this one resulted in blkfront_remove (from xenbus) racing >against blkif_release (run from close(bdev)).=20 > >Both running for their respective kfree(info) vs. subsequent >dereferences. Or just to leak info entirely. > >We only had blkfront_closing() on either thread before, which serializes >around the bd_mutex. > >I'm currently thinking that info now rather wants a refcount of its own. >Ideally replacing is_ready entirely, maybe. > >Any thoughts? Could you check the fixup patch I sent just a couple of minutes ago (paralleling c/s 993 on the 2.6.18 tree)? Thanks, Jan