Return-path: Received: from crystal.sipsolutions.net ([195.210.38.204]:55863 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751740AbYDDPpv (ORCPT ); Fri, 4 Apr 2008 11:45:51 -0400 Subject: Re: 2.6.25-rc8-mm1 -- INFO: possible circular locking dependency detected (while using iw to debug a wireless issue) From: Johannes Berg To: Miles Lane Cc: Jiri Benc , linux-wireless , Jouni Malinen , Andrew Morton , netdev , ALSA development , Thomas Graf In-Reply-To: (sfid-20080403_154132_439220_5408BAC7) References: (sfid-20080403_154132_439220_5408BAC7) Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-O0Z1pbA2EKqKyXcQDwjG" Date: Fri, 04 Apr 2008 17:45:36 +0200 Message-Id: <1207323936.19189.58.camel@johannes.berg> (sfid-20080404_164555_789688_16C09391) Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: --=-O0Z1pbA2EKqKyXcQDwjG Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Thu, 2008-04-03 at 10:41 -0400, Miles Lane wrote: > After collecting the wireshark log, I found this in my messages log: Below is a better version of the trace Miles sent me privately, but I have no idea what would be causing it. I don't think it's related to wireless. =EF=BB=BF=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D [ INFO: possible circular locking dependency detected ] 2.6.25-rc8-mm1 #15 ------------------------------------------------------- iw/9417 is trying to acquire lock: (genl_mutex){--..}, at: [ctrl_dumpfamily+0x37/0xda] ctrl_dumpfamily+0x37/0x= da but task is already holding lock: (nlk->cb_mutex){--..}, at: [netlink_dump+0x39/0x22e] netlink_dump+0x39/0x22= e which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (nlk->cb_mutex){--..}: [__lock_acquire+0xa02/0xbaf] __lock_acquire+0xa02/0xbaf [lock_acquire+0x76/0x9d] lock_acquire+0x76/0x9d [snd_mixer_oss:mutex_lock_nested+0xd5/0x67b] mutex_lock_nested+0xd5/0x274 [netlink_dump_start+0xbd/0x15a] netlink_dump_start+0xbd/0x15a [genl_rcv_msg+0x9d/0x13a] genl_rcv_msg+0x9d/0x13a [netlink_rcv_skb+0x30/0x75] netlink_rcv_skb+0x30/0x75 [genl_rcv+0x1e/0x2e] genl_rcv+0x1e/0x2e [cfg80211:netlink_unicast+0x1c1/0x1867] netlink_unicast+0x1c1/0x293 [netlink_sendmsg+0x21f/0x22c] netlink_sendmsg+0x21f/0x22c [sock_sendmsg+0xca/0xe1] sock_sendmsg+0xca/0xe1 [sys_sendmsg+0x14d/0x1a8] sys_sendmsg+0x14d/0x1a8 [sys_socketcall+0x163/0x17e] sys_socketcall+0x163/0x17e [sysenter_past_esp+0x6d/0xc5] sysenter_past_esp+0x6d/0xc5 [] 0xffffffff -> #0 (genl_mutex){--..}: [__lock_acquire+0x929/0xbaf] __lock_acquire+0x929/0xbaf [lock_acquire+0x76/0x9d] lock_acquire+0x76/0x9d [snd_mixer_oss:mutex_lock_nested+0xd5/0x67b] mutex_lock_nested+0xd5/0x274 [ctrl_dumpfamily+0x37/0xda] ctrl_dumpfamily+0x37/0xda [netlink_dump+0x51/0x22e] netlink_dump+0x51/0x22e [netlink_recvmsg+0x156/0x203] netlink_recvmsg+0x156/0x203 [sock_recvmsg+0xd1/0xe9] sock_recvmsg+0xd1/0xe9 [sys_recvmsg+0xf2/0x17f] sys_recvmsg+0xf2/0x17f [sys_socketcall+0x16f/0x17e] sys_socketcall+0x16f/0x17e [sysenter_past_esp+0x6d/0xc5] sysenter_past_esp+0x6d/0xc5 [] 0xffffffff other info that might help us debug this: 1 lock held by iw/9417: #0: (nlk->cb_mutex){--..}, at: [netlink_dump+0x39/0x22e] netlink_dump+0x39= /0x22e stack backtrace: Pid: 9417, comm: iw Not tainted 2.6.25-rc8-mm1 #15 [print_circular_bug_tail+0x5b/0x66] print_circular_bug_tail+0x5b/0x66 [print_circular_bug_header+0xa5/0xb0] ? print_circular_bug_header+0xa5/0xb0 [__lock_acquire+0x929/0xbaf] __lock_acquire+0x929/0xbaf [lock_acquire+0x76/0x9d] lock_acquire+0x76/0x9d [ctrl_dumpfamily+0x37/0xda] ? ctrl_dumpfamily+0x37/0xda [snd_mixer_oss:mutex_lock_nested+0xd5/0x67b] mutex_lock_nested+0xd5/0x274 [ctrl_dumpfamily+0x37/0xda] ? ctrl_dumpfamily+0x37/0xda [ctrl_dumpfamily+0x37/0xda] ? ctrl_dumpfamily+0x37/0xda [ctrl_dumpfamily+0x37/0xda] ctrl_dumpfamily+0x37/0xda [netlink_dump+0x51/0x22e] netlink_dump+0x51/0x22e [mac80211:kfree_skb+0x40/0x45] ? kfree_skb+0x40/0x45 [netlink_recvmsg+0x156/0x203] netlink_recvmsg+0x156/0x203 [sock_sendmsg+0xca/0xe1] ? sock_sendmsg+0xca/0xe1 [sock_recvmsg+0xd1/0xe9] sock_recvmsg+0xd1/0xe9 [] ? autoremove_wake_function+0x0/0x30 [snd_pcm_oss:copy_from_user+0x3b/0x236] ? copy_from_user+0x3b/0x5e [verify_iovec+0x40/0x70] ? verify_iovec+0x40/0x70 [sys_recvmsg+0xf2/0x17f] sys_recvmsg+0xf2/0x17f [snd_hda_intel:_spin_unlock_irqrestore+0x56/0x6c] ? _spin_unlock_irqrestore= +0x56/0x6c [paravirt_get_lazy_mode+0xe/0x1b] ? paravirt_get_lazy_mode+0xe/0x1b [crypto_algapi:kunmap_atomic+0x9e/0x2e8e] ? kunmap_atomic+0x9e/0xbb [handle_mm_fault+0x7aa/0x7bb] ? handle_mm_fault+0x7aa/0x7bb [sys_socketcall+0x16f/0x17e] sys_socketcall+0x16f/0x17e [processor:trace_hardirqs_on+0xf0/0x5d38] ? trace_hardirqs_on+0xf0/0x12c [sysenter_past_esp+0x6d/0xc5] sysenter_past_esp+0x6d/0xc5 --=-O0Z1pbA2EKqKyXcQDwjG Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Comment: Johannes Berg (powerbook) iQIVAwUAR/ZNH6Vg1VMiehFYAQLhXw/9HGc09vE2SEidrFYGRajzhwxEZoxXbDTi 175k9XXL3mnVnBdlWDZ2Uh4p7fpYhWbrgzvW9KIb5KN+AHL/96/sZn/jyob2T1/i gSpDjjZrxnMdkQlv7Ym7ZktTjpNAp84N52jbXfY1uaFs4koIjwb6aixlJIjuYmkQ Dz0r90SXsiRVibYwzco8baaD/8N0LFYhEwVDShRgBRgNS9FMHdUZ4pyCVE4ulBIS qEbv6R4DorZgyQsdCQiF6cOOYakd7cbT/S0yk82j4LVmiMaaU5jqp3nE3TSheZbw q20/hNklUTitt6/cU5mpvIYtlc5/YnLjmhxqWDmeY/xAVo2ilvCRm1g6HCepxf14 XVONmCb4sMOPeHkUOefjOlKAfDnD2oIYEWX3mnNJYqkdejU8Y+dcAgjtGdhZPWZ5 Eit+HOSST9B7OOY+S7nVYVhJf62EThsTHBUJCWe3Viue8mZbA1NiOsk+hqQXl02o BpI1K5H8bBVOFw3At+5mmGX/js72lspx3kv2c+6qLwwYfyqfJCz6m0YmyL9V8x22 Sp+X+Q4givNQMsyvBa/MtatkWojmrE7qV0AuWjG2Rjyvpbp2hISd6T99y+Gh94xi 4tFzTUF/saQB52BrNWkN7wi6tJWTvIF1dCQHTyNmoCrip6LyTL6EycsIqM7GvAWn rR5IO7Std38= =fomS -----END PGP SIGNATURE----- --=-O0Z1pbA2EKqKyXcQDwjG--