From: Jiri Slaby Subject: Re: 2.6.25-git2: BUG: unable to handle kernel paging request at ffffffffffffffff Date: Mon, 21 Apr 2008 23:18:26 +0200 Message-ID: <480D04A2.5000006@gmail.com> References: <200804211812.16994.rjw@sisk.pl> <20080421.133940.52972455.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: torvalds@linux-foundation.org, rjw@sisk.pl, linux-kernel@vger.kernel.org, mingo@elte.hu, akpm@linux-foundation.org, linux-ext4@vger.kernel.org, herbert@gondor.apana.org.au, paulmck@us.ibm.com, Zdenek Kabelac To: David Miller Return-path: Received: from nf-out-0910.google.com ([64.233.182.188]:1090 "EHLO nf-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752433AbYDUVSm (ORCPT ); Mon, 21 Apr 2008 17:18:42 -0400 Received: by nf-out-0910.google.com with SMTP id g13so651956nfb.21 for ; Mon, 21 Apr 2008 14:18:38 -0700 (PDT) In-Reply-To: <20080421.133940.52972455.davem@davemloft.net> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 04/21/2008 10:39 PM, David Miller wrote: > From: Linus Torvalds > Date: Mon, 21 Apr 2008 09:54:07 -0700 (PDT) > >> What I find interesting is that at least for me, I have the SLAB bucket >> size for nf_conntrack_expect being 208 bytes. And the *biggest* merge by >> far after 2.6.25 so far has been networking (and conntrack in particular) >> >> Is that a smoking gun? Not necessarily. But it *is* intriguing. But there >> are other possible clashes (the 192-byte bucket has several different >> suspects, and not all of them are in networking).1 > > I think you might be onto something here. > > The "mask" member of struct nf_conntrack_expect could be reasonably > all 1's like the value reported in the crash that begins this > thread. > > Do we know the offset within the object at which this all 1's > value is found? > > My rough calculations show that on 32-bit that expect->mask member is > at offset 56 and on 64-bit it should be at offset 72. Does that > match up to the offset of the filp or whatever bit being corrupted? dentry.d_name.name is 56 on 64-bit (my memcmp crashes) dentry.d_hash.next is 24 (crashed at least 3 times here, rafael's one) dentry.d_op is 136 (crash below) It's spreading :/. ---------- Forwarded message ---------- From: Zdenek Kabelac Date: 21.4.2008 11:14 Subject: BUG: unable to handle kernel NULL pointer at d_free+0x18/0x80 To: Kernel development list Hello This oops appeared in my log - unsure how it is related to my DVB-T tuner test before. But I've also seen another weird resume with some similar crash. Happens with 2.6.25 - commit 48a86f548fb74928f9a466f52527e83fecdb4575 (T61, 2GB) BUG: unable to handle kernel NULL pointer dereference at 0000000000000110 IP: [d_free+24/128] d_free+0x18/0x80 PGD 0 Oops: 0000 [1] PREEMPT SMP CPU 0 Modules linked in: usb_storage dvb_usb_af9015 dvb_usb_dibusb_common dib3000mc dibx000_common dvb_usb dvb_core tun nls_iso8859_2 nls_cp852 vfat fat i915 drm ipt_MASQUERADE iptable_nat nf_nat nf_conntrack_ipv4 xt_state nf_conntrack ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge llc nfsd lockd nfs_acl auth_rpcgss exportfs autofs4 sunrpc binfmt_misc dm_mirror dm_log dm_multipath dm_mod uinput kvm_intel kvm snd_hda_intel arc4 ecb snd_seq_oss crypto_blkcipher snd_seq_midi_event snd_seq cryptomgr snd_seq_device snd_pcm_oss crypto_algapi iwl3945 mac80211 e1000e psmouse snd_mixer_oss rtc_cmos evdev rtc_core thinkpad_acpi video snd_pcm mmc_block sdhci mmc_core snd_timer iTCO_wdt iTCO_vendor_support battery backlight nvram rtc_lib i2c_i801 i2c_core ac snd soundcore snd_page_alloc intel_agp output serio_raw cfg80211 button uhci_hcd ohci_hcd ehci_hcd usbcore [last unloaded: dvb_core] Pid: 210, comm: kswapd0 Not tainted 2.6.25 #56 RIP: 0010:[d_free+24/128] [d_free+24/128] d_free+0x18/0x80 RSP: 0018:ffff81007ced9cf0 EFLAGS: 00010206 RAX: 00000000000000f0 RBX: ffff8100202723d8 RCX: 0000000000000132 RDX: 0000000000005e5d RSI: ffff81007ced4048 RDI: ffff8100202723d8 RBP: ffff81007ced9d00 R08: 0000000000000002 R09: d37a6f4de9bd37a7 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8100202723d8 R13: ffff81007c9329d8 R14: ffff8100202723e0 R15: 0000000000000029 FS: 0000000000000000(0000) GS:ffffffff81486000(0000) knlGS:0000000000000000 CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b CR2: 0000000000000110 CR3: 0000000001001000 CR4: 00000000000026e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process kswapd0 (pid: 210, threadinfo ffff81007ced8000, task ffff81007ced4000) Stack: ffff8100202723d8 ffff81007b7e73d8 ffff81007ced9d20 ffffffff810cb3eb ffff8100202723d8 0000000000000000 ffff81007ced9d40 ffffffff810cb4d5 ffff8100202723d8 ffff8100202723d8 ffff81007ced9d80 ffffffff810cb642 Call Trace: [d_kill+59/96] d_kill+0x3b/0x60 [prune_one_dentry+197/240] prune_one_dentry+0xc5/0xf0 [prune_dcache+322/512] prune_dcache+0x142/0x200 [shrink_dcache_memory+65/80] shrink_dcache_memory+0x41/0x50 [shrink_slab+274/480] shrink_slab+0x112/0x1e0 [kswapd+1232/1552] kswapd+0x4d0/0x610 [isolate_pages_global+0/64] ? isolate_pages_global+0x0/0x40 [autoremove_wake_function+0/64] ? autoremove_wake_function+0x0/0x40 [_spin_unlock_irqrestore+69/144] ? _spin_unlock_irqrestore+0x45/0x90 [kswapd+0/1552] ? kswapd+0x0/0x610 [kthread+73/144] kthread+0x49/0x90 [child_rip+10/18] child_rip+0xa/0x12 [restore_args+0/48] ? restore_args+0x0/0x30 [kthread+0/144] ? kthread+0x0/0x90 [child_rip+0/18] ? child_rip+0x0/0x12 Code: 95 49 81 e8 ab ff 21 00 5b 41 5c c9 c3 66 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb 48 83 ec 08 48 8b 87 b8 00 00 00 48 85 c0 74 0b <48> 8b 40 20 48 85 c0 74 02 ff d0 48 83 7b 50 00 74 1e 48 8d bb RIP [d_free+24/128] d_free+0x18/0x80 RSP CR2: 0000000000000110 ---[ end trace ca143223eefdc828 ]---