Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763779AbXLPWZC (ORCPT ); Sun, 16 Dec 2007 17:25:02 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757897AbXLPWYw (ORCPT ); Sun, 16 Dec 2007 17:24:52 -0500 Received: from smtp2.linux-foundation.org ([207.189.120.14]:34005 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756535AbXLPWYu (ORCPT ); Sun, 16 Dec 2007 17:24:50 -0500 Date: Sun, 16 Dec 2007 14:23:44 -0800 From: Andrew Morton To: "Miles Lane" Cc: "Herbert Xu" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Fw: [PACKET]: Fix /proc/net/packet crash due to bogus private pointer Message-Id: <20071216142344.802ceaf4.akpm@linux-foundation.org> In-Reply-To: References: <20071215203637.179878aa.akpm@linux-foundation.org> <20071215235604.1a3f970a.akpm@linux-foundation.org> <20071216081936.GA3042@gondor.apana.org.au> X-Mailer: Sylpheed 2.4.1 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3543 Lines: 75 On Sun, 16 Dec 2007 15:10:14 -0500 "Miles Lane" wrote: > On Dec 16, 2007 3:19 AM, Herbert Xu wrote: > > On Sat, Dec 15, 2007 at 11:56:04PM -0800, Andrew Morton wrote: > > > On Sun, 16 Dec 2007 01:37:01 -0500 "Miles Lane" wrote: > > > > > > > > On Sun, Dec 16, 2007 at 11:07:07AM +0800, Herbert Xu wrote: > > > > So I posted this patch after 19:00 PST on 15 Dec. > > > > > > Dec 15 13:44:39 syntropy kernel: #0: (&p->lock){--..}, at: > > > > [crypto_algapi:seq_read+0x25/0x191c1] seq_read+0x25/0x26f > > > > > > So your kernel is still feeding garbage into lockdep. > > > > > > Are you really really sure that kernel had Herbert's patch applied? > > > > The above log message is stamped as 13:44 PST. I gotta say > > this doesn't look good :) > > Yes, I did have the patch applied, but I had reenabled LOCKDEP_DEBUG. > I just tried with the LOCKDEP_DEBUG stuff turned off, and with this > configuration, the problem is resolved. It seems that the patch > you made does fix the problem with /proc/net/packet. This new issue > seems to be a different problem. > > So, I tried building another kernel with LOCKDEP enabled (.config attached): > With this kernel, I got: > > Dec 16 11:21:39 syntropy kernel: [ 278.723108] process `tail' is > using deprecated sysctl (syscall) net.ipv6.neigh.default.retrans_time; > Use net.ipv6.neigh.default.retrans_time_ms instead. > Dec 16 11:21:40 syntropy kernel: [ 279.226103] in_atomic():1, irqs_disabled():0 > Dec 16 11:21:40 syntropy kernel: [ 279.226106] no locks held by tail/6208. > Dec 16 11:21:40 syntropy kernel: [ 279.226109] Pid: 6208, comm: tail > Not tainted 2.6.24-rc5-mm1 #5 > Dec 16 11:21:40 syntropy kernel: [ 279.226112] > [show_trace_log_lvl+0x12/0x25] show_trace_log_lvl+0x12/0x25 > Dec 16 11:21:40 syntropy kernel: [ 279.226121] [show_trace+0xd/0x10] > show_trace+0xd/0x10 > Dec 16 11:21:40 syntropy kernel: [ 279.226126] > [sbp2:dump_stack+0x57/0x17c1] dump_stack+0x57/0x5f > Dec 16 11:21:40 syntropy kernel: [ 279.226130] > [firewire_core:__might_sleep+0xd7/0x29a] __might_sleep+0xd7/0xde > Dec 16 11:21:40 syntropy kernel: [ 279.226136] > [parport:copy_to_user+0x32/0xd13f] copy_to_user+0x32/0x47 > Dec 16 11:21:40 syntropy kernel: [ 279.226141] > [add_to_pagemap+0x29/0x56] add_to_pagemap+0x29/0x56 > Dec 16 11:21:40 syntropy kernel: [ 279.226147] > [pagemap_pte_range+0x74/0xb1] pagemap_pte_range+0x74/0xb1 > Dec 16 11:21:40 syntropy kernel: [ 279.226151] > [walk_page_range+0x115/0x1dc] walk_page_range+0x115/0x1dc > Dec 16 11:21:40 syntropy kernel: [ 279.226157] > [pagemap_read+0x154/0x1e8] pagemap_read+0x154/0x1e8 > Dec 16 11:21:40 syntropy kernel: [ 279.226161] [vfs_read+0xa2/0x11e] > vfs_read+0xa2/0x11e > Dec 16 11:21:40 syntropy kernel: [ 279.226166] [sys_read+0x3b/0x60] > sys_read+0x3b/0x60 > Dec 16 11:21:40 syntropy kernel: [ 279.226170] > [sysenter_past_esp+0x6b/0xc1] sysenter_past_esp+0x6b/0xc1 (Can you find a way to fix that wordwrapping please?) Yes, this is a different bug - the pagemap stuff is doing userspace access under kmap_atomic() - we discovered this a couple of days ago and Matt has been informed. It's relatively harmless and if that's the only problem you're observing then I think we're OK here. -- 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/