Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758608Ab0FVOIU (ORCPT ); Tue, 22 Jun 2010 10:08:20 -0400 Received: from mail-gw0-f46.google.com ([74.125.83.46]:37782 "EHLO mail-gw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750947Ab0FVOIS convert rfc822-to-8bit (ORCPT ); Tue, 22 Jun 2010 10:08:18 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=QMrNGxmXBBGMUTpywZET+9GIYSpzQoawbF6SHA9iUbVLFsrrFC2RUGAUiV4EkzpRly DqelE50xGlhJSCR8uSM0DfCN7ZzMjprsQSGzOPdby6oReVLlPt+/+chSlffL0IuO0wcM nevCY/DLGNyAPdALtZryCpHDOFaZ0SDL8prS4= MIME-Version: 1.0 In-Reply-To: <20100621202854.de928e0a.akpm@linux-foundation.org> References: <20100621202854.de928e0a.akpm@linux-foundation.org> Date: Tue, 22 Jun 2010 08:08:17 -0600 Message-ID: Subject: Re: 2.6.34 Crash in dmaengine_put() From: Jeffrey Merkey To: Andrew Morton Cc: linux-kernel@vger.kernel.org, Dan Williams Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1075 Lines: 26 OK. This bug occurs if you OR in the IFF_UP flag while creating virtual interfaces without going through the normal ifup/ifdown scripts. Looks like a hole. I will post the trace shortly. It's easy to reproduce, take the dummy net driver, OR in the IFF_UP flag in dummy_setup, and watch the kernel crash. Jeff On Mon, Jun 21, 2010 at 9:28 PM, Andrew Morton wrote: > On Mon, 21 Jun 2010 20:57:40 -0600 Jeffrey Merkey wrote: > >> If someone sets the IFF_UP flags in the netdev structure without going >> through ifup userspace stuff, during unregister of the the netdev >> the dmaengine-put code will decrement the reference counter negative, >> and crash at BUG! in the driver/dma/dmaengine.c code. ?This seems >> busted. >> > > Please send a copy of the kernel BUG trace. > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/