Return-path: Received: from charlotte.tuxdriver.com ([70.61.120.58]:51152 "EHLO smtp.tuxdriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753795AbYLIPAL (ORCPT ); Tue, 9 Dec 2008 10:00:11 -0500 Date: Tue, 9 Dec 2008 09:54:39 -0500 From: "John W. Linville" To: Johannes Berg Cc: Christian Lamparter , linux-wireless@vger.kernel.org, Larry Finger Subject: Re: [PATCH v2] p54usb: rewriting rx/tx routines to make use of usb_anchor's facilities Message-ID: <20081209145439.GB3653@tuxdriver.com> (sfid-20081209_160016_884567_50685F3A) References: <200812091514.37634.chunkeey@web.de> <20081209143530.GA3653@tuxdriver.com> <1228833999.1029.0.camel@johannes.berg> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1228833999.1029.0.camel@johannes.berg> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Tue, Dec 09, 2008 at 03:46:39PM +0100, Johannes Berg wrote: > On Tue, 2008-12-09 at 09:35 -0500, John W. Linville wrote: > > On Tue, Dec 09, 2008 at 03:14:37PM +0100, Christian Lamparter wrote: > > > Alan Stern found several flaws in p54usb's implementation and annotated: > > > "usb_kill_urb() and similar routines do not expect an URB's completion > > > routine to deallocate it. This is almost obvious -- if the URB is deallocated > > > before the completion routine returns then there's no way for usb_kill_urb > > > to detect when the URB actually is complete." > > > > > > This patch addresses all known limitations in the old implementation and fixes > > > khub's "use-after-freed" hang, when SLUB debug's poisoning option is enabled. > > > > > > Signed-off-by: Christian Lamparter > > > Cc: stable@kernel.org > > > > That's a big patch for so late in the cycle. Is there a bugzilla open for it? > > No, but we can open one ;) It's strange, but nobody but me apparently > found the bug so far, even though it has been in there forever. Might be > due to slub debugging being disabled by default even if you enable > SLUB_DEBUG in Kconfig (you also need to enable SLUB_DEBUG_ON) It might be helpful to have open a bug that includes a backtrace or something. John -- John W. Linville Linux should be at the core linville@tuxdriver.com of your literate lifestyle.