Subject: kernel BUG at kernel/timer.c:748!

From: Dave Jones <[email-masked]>
Date: Wed, 5 Sep 2012 00:35:23 -0400

Just hit this bug on 3.6-rc4.

The BUG is..

	BUG_ON(!timer->function);

Not much to go on... Any thoughts on what I could add to get
more debug info on which protocol etc this was ?

	Dave

kernel BUG at kernel/timer.c:748!
invalid opcode: 0000 [#1] SMP 
Modules linked in: tun fuse ipt_ULOG binfmt_misc nfnetlink nfc caif_socket caif phonet can llc2 pppoe pppox ppp_generic slhc irda crc_ccitt rds af_key decnet rose x25 atm netrom appletalk ipx p8023 psnap p8022 llc ax25 nfsv3 nfs_acl nfs fscache lockd sunrpc bluetooth rfkill ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack kvm_intel kvm crc32c_intel ghash_clmulni_intel microcode pcspkr i2c_i801 e1000e uinput i915 video i2c_algo_bit drm_kms_helper drm i2c_core
CPU 3 
Pid: 12330, comm: trinity-child3 Not tainted 3.6.0-rc4+ #36
RIP: 0010:[<ffffffff810813f5>]  [<ffffffff810813f5>] mod_timer+0x2c5/0x2f0
RSP: 0018:ffff88000dfd7e08  EFLAGS: 00010246
RAX: 000000000000001a RBX: ffff880122d62948 RCX: 000000000000001a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88000dfd7e10
RBP: ffff88000dfd7e48 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000001517000 R11: 0000000000000246 R12: 000000016c000000
R13: 000000016c12bcb1 R14: ffff8801236cee00 R15: 00000000ffffff01
FS:  00007fa96745f740(0000) GS:ffff880148200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000100ff000 CR3: 0000000099344000 CR4: 00000000001407e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process trinity-child3 (pid: 12330, threadinfo ffff88000dfd6000, task ffff880090890000)
Stack:
 ffffffff8154cb6d 0000000007b5edf7 ffff88000dfd7e28 ffff880122d62520
 0000000000000009 0000000000000004 ffff8801236cee00 00000000ffffff01
 ffff88000dfd7e68 ffffffff8154c79c ffffffff81550e6c ffff880122d62520
Call Trace:
 [<ffffffff8154cb6d>] ? lock_sock_nested+0x8d/0xa0
 [<ffffffff8154c79c>] sk_reset_timer+0x1c/0x30
 [<ffffffff81550e6c>] ? sock_setsockopt+0x8c/0x960
 [<ffffffff815a84a0>] inet_csk_reset_keepalive_timer+0x20/0x30
 [<ffffffff815c018d>] tcp_set_keepalive+0x3d/0x50
 [<ffffffff81551703>] sock_setsockopt+0x923/0x960
 [<ffffffff810ddf76>] ? trace_hardirqs_on_caller+0x16/0x1e0
 [<ffffffff811db0ac>] ? fget_light+0x24c/0x520
 [<ffffffff8154af86>] sys_setsockopt+0xc6/0xe0
 [<ffffffff816a50ed>] system_call_fastpath+0x1a/0x1f
Code: 00 74 43 9c 58 0f 1f 44 00 00 f6 c4 02 0f 84 14 ff ff ff eb 93 48 c7 c7 20 48 c3 81 e8 f5 70 05 00 85 c0 0f 85 fe fe ff ff eb b7 <0f> 0b 48 8b 75 08 48 89 df e8 3d f6 ff ff e9 b2 fd ff ff 4d 89 
RIP  [<ffffffff810813f5>] mod_timer+0x2c5/0x2f0
 RSP <ffff88000dfd7e08>
---[ end trace 7e7b5910138e49a3 ]---