Return-path: Received: from mail.deathmatch.net ([70.167.247.36]:3262 "EHLO mail.deathmatch.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754230AbZBXN60 (ORCPT ); Tue, 24 Feb 2009 08:58:26 -0500 Date: Tue, 24 Feb 2009 08:58:17 -0500 From: Bob Copeland To: Nick Kossifidis Cc: Jiri Slaby , Sitsofe Wheeler , Frederic Weisbecker , linux-kernel@vger.kernel.org, linux-wireless@vger.kernel.org, ath5k-devel@venema.h4ckr.net, "Luis R. Rodriguez" Subject: Re: [TIP] BUG kmalloc-4096: Poison overwritten (ath5k_rx_skb_alloc) Message-ID: <20090224135817.GB6019@hash.localnet> (sfid-20090224_145829_042008_75661FAF) References: <49A13E91.1090601@gmail.com> <20090222122036.GC5538@silver.sucs.org> <20090222144742.GA6078@nowhere> <20090222170201.GA27360@silver.sucs.org> <49A1CA01.9030501@gmail.com> <49A1DDD2.7040706@gmail.com> <20090223152724.M82409@bobcopeland.com> <49A321BA.2040500@gmail.com> <49A326A4.8090103@gmail.com> <40f31dec0902231508l512af5b7w68cfcc0bdf3cfa87@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <40f31dec0902231508l512af5b7w68cfcc0bdf3cfa87@mail.gmail.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Tue, Feb 24, 2009 at 01:08:03AM +0200, Nick Kossifidis wrote: > He does an extra check... > > /* > * Given the use of a self-linked tail be very sure that the hw is > * done with this descriptor; the hw may have done this descriptor > * once and picked it up again...make sure the hw has moved on. > */ > if ((ands->ds_rxstatus1&AR_Done) == 0 && OS_REG_READ(ah, AR_RXDP) == pa) > return HAL_EINPROGRESS; Sounds like we definitely need that. If the hw uses up all the dma buffers in one go, there's a good chance we can send the skb to mac80211 while the hardware is still using it. I guess an easy way to test would be to set the max rx buffers to 3 or so and watch the fireworks. -- Bob Copeland %% www.bobcopeland.com