On Mon, Sep 12, 2011 at 03:17:00PM -0700, Simon Kirby wrote: > On Thu, Sep 08, 2011 at 03:24:20PM -0700, Simon Kirby wrote: > > > This box primarily does most of its VFS stuff over lots of NFS mounts, > > but has some local EXT3 filesystems. This has happened a couple of times: > > > > BUG: unable to handle kernel NULL pointer dereference at 00000000000000b8 >... > Got a few more identical Oopses on another box running slightly past > 3.1-rc5 (79016f648872549392d232cd648bd02298c2d2bb). It seems to be > do_rmdir()'s mutex_unlock() call. > > I'm building -rc6 with CONFIG_DEBUG_MUTEXES now. ...and not much more help with CONFIG_DEBUG_MUTEXES, from 3.1-rc6: BUG: unable to handle kernel NULL pointer dereference at 00000000000000a4 IP: [<ffffffff816adc93>] __mutex_unlock_slowpath+0x53/0x140 PGD 13c6c4067 PUD 2256fc067 PMD 0 Oops: 0002 [#1] SMP CPU 2 Modules linked in: ipmi_devintf ipmi_si ipmi_msghandler xt_recent nf_conntrack_ftp xt_state xt_owner nf_conntrack_ipv4 nf_conntrack nf_defrag_ipv4 bnx2 Pid: 27658, comm: php Not tainted 3.1.0-rc6-hw-mudbg+ #32 Dell Inc. PowerEdge 1950/0TT740 RIP: 0010:[<ffffffff816adc93>] [<ffffffff816adc93>] __mutex_unlock_slowpath+0x53/0x140 RSP: 0018:ffff8800b65e1e28 EFLAGS: 00010046 RAX: 0000000000000100 RBX: ffff88001bcece48 RCX: ffff88001bd05348 RDX: 0000000040000200 RSI: ffff8800916cf6c0 RDI: 00000000000000a0 RBP: ffff8800b65e1e48 R08: 00000000043205bc R09: ffffea00011340c0 R10: 0000000000000000 R11: 0000000000000002 R12: 00000000000000a0 R13: 00000000000000a4 R14: 0000000000000246 R15: 00007f7fe2d15680 FS: 00007f7fe2e1f720(0000) GS:ffff88022fc80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000a4 CR3: 0000000215c16000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process php (pid: 27658, threadinfo ffff8800b65e0000, task ffff8800175d4320) Stack: ffff88001bcece48 00000000fffffffe ffff8800916cf6c0 00007f7fe2d146a8 ffff8800b65e1e58 ffffffff816add89 ffff8800b65e1e88 ffffffff8110ec70 ffff8800b65e1e98 ffff8800916cf6c0 ffff8800b65e1e98 0000000000000000 Call Trace: [<ffffffff816add89>] mutex_unlock+0x9/0x10 [<ffffffff8110ec70>] vfs_rmdir+0xb0/0x100 [<ffffffff8110ed96>] do_rmdir+0xd6/0x130 [<ffffffff81102063>] ? fput+0x1c3/0x260 [<ffffffff810fe648>] ? filp_close+0x68/0xa0 [<ffffffff8110ee41>] sys_rmdir+0x11/0x20 [<ffffffff816b6f3b>] system_call_fastpath+0x16/0x1b Code: 75 1b 65 48 8b 04 25 c8 b5 00 00 48 63 80 44 e0 ff ff a9 00 ff ff 07 0f 85 bb 00 00 00 9c 41 5e fa b8 00 01 00 00 4d 8d 6c 24 04 <f0> 66 41 0f c1 45 00 38 e0 74 08 f3 90 41 8a 45 00 eb f4 44 8b RIP [<ffffffff816adc93>] __mutex_unlock_slowpath+0x53/0x140 RSP <ffff8800b65e1e28> CR2: 00000000000000a4 ---[ end trace f515ec8376bdb799 ]--- How can I further debug this? At this point, it seems to be happening several times daily. Simon- -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
