[openib-general] oops after rmmod ib_cm when stopping iSER

[Erez Zilber]

Sean,

When stopping iSER, we run 'modprobe -r ib_iser'. Then, we see an oops 
(below). In order to check which module caused that oops, I replaced the 
'modprobe -r' call with rmmod for each module:

rmmod ib_iser
rmmod libiscsi
rmmod scsi_transport_iscsi
rmmod rdma_cm
rmmod ib_addr
rmmod ib_cm

If I wait a few seconds before the removal of ib_cm, everything is ok.

thyme login: Sep 27 09:50:08 thyme kernel: iser: 
iscsi_iser_ep_disconnect:ib conn ffff81005e426000 state 2
Sep 27 09:50:08 thyme kernel: iser: iser_cq_tasklet_fn:comp w. error op 
0 status 5
Sep 27 09:50:08 thyme last message repeated 3 times
Sep 27 09:50:08 thyme kernel: iser: iser_cma_handler:event 10 conn 
ffff81005e426000 id ffff81006c304a00
Sep 27 09:50:08 thyme kernel: iser: iser_free_ib_conn_res:freeing conn 
ffff81005e426000 cma_id ffff81006c304a00 fmr pool ffff8100560f2e40 qp f0
Sep 27 09:50:08 thyme kernel: iser: iser_device_try_release:device 
ffff8100796037c0 refcount 0
Sep 27 09:50:09 thyme kernel: cma_cleanup: entry
Sep 27 09:50:09 thyme kernel: cma_cleanup: calling destroy_workqueue
Sep 27 09:50:09 thyme kernel: cma_cleanup: calling idr_destroy(&sdp_ps)
Sep 27 09:50:09 thyme kernel: cma_cleanup: calling idr_destroy(&tcp_ps)
Sep 27 09:50:09 thyme kernel: cma_cleanup: exit
Sep 27 09:50:09 thyme kernel: ib_cm_cleanup: entry
Sep 27 09:50:09 thyme kernel: ib_cm_cleanup: calling ib_unregister_client
Sep 27 09:50:09 thyme kernel: ib_cm_cleanup: calling idr_destroy
Sep 27 09:50:09 thyme kernel: ib_cm_cleanup: exit
Unable to handle kernel paging request at ffffffff8b02e017 RIP:
[<ffffffff8024133c>] delayed_work_timer_fn+0x2c/0x40
PGD 203027 PUD 205027 PMD 0
Oops: 0000 [1] SMP
CPU 3
Modules linked in: ib_uverbs ib_ipoib ib_sa autofs usbserial parport_pc 
lp parport edd cpufreq_userspace acpi_cpufreq thermal processor fan bud
Pid: 0, comm: swapper Not tainted 2.6.18-rc4-ga2d9f966-dirty #1
RIP: 0010:[<ffffffff8024133c>] [<ffffffff8024133c>] 
delayed_work_timer_fn+0x2c/0x40
RSP: 0018:ffff81007e36fef8 EFLAGS: 00010246
RAX: ffffffff8b02dfff RBX: 0000000000000100 RCX: ffff81006b152d20
RDX: 0000000000000003 RSI: ffff810068576a00 RDI: ffff810068576a00
RBP: ffff81007e340000 R08: efe9331445cb91ec R09: ffff81007e3a8008
R10: 0000000000000000 R11: 0000000000000246 R12: ffffffff80241310
R13: ffff81007e36ff00 R14: 000000000000000a R15: 0000000000000003
FS: 0000000000000000(0000) GS:ffff81007e344b40(0000) knlGS:0000000000000000
CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: ffffffff8b02e017 CR3: 0000000060a44000 CR4: 00000000000006e0
Process swapper (pid: 0, threadinfo ffff81007e36a000, task ffff81007e347080)
Stack: ffffffff80239826 ffff81007e36ff00 ffff81007e36ff00 ffff81000102ac20
0000000000000000 0000000000000096 0000000000000011 ffffffff8065a110
ffffffff806b2b20 0000000000000003 ffffffff80235d0b ffff81007e36ff48
Call Trace:
<IRQ> [<ffffffff80239826>] run_timer_softirq+0x156/0x1e0
[<ffffffff80235d0b>] __do_softirq+0x6b/0xe0
[<ffffffff8020aee8>] call_softirq+0x1c/0x34
[<ffffffff8020c92c>] do_softirq+0x2c/0x90
[<ffffffff802083e0>] mwait_idle+0x0/0x50
[<ffffffff8020a886>] apic_timer_interrupt+0x66/0x6c
<EOI> [<ffffffff80208416>] mwait_idle+0x36/0x50
[<ffffffff80208e1a>] cpu_idle+0x6a/0x90
[<ffffffff8067f919>] start_secondary+0x499/0x4b0


Code: 48 8b 3c d0 e9 4b ff ff ff 66 66 66 90 66 66 66 90 66 66 90
RIP [<ffffffff8024133c>] delayed_work_timer_fn+0x2c/0x40
RSP <ffff81007e36fef8>
CR2: ffffffff8b02e017
<0>Kernel panic - not syncing: Aiee, killing interrupt handler!

-- 

____________________________________________________________

Erez Zilber | 972-9-971-7689

Software Engineer, Storage Team

Voltaire – _The Grid Backbone_

__

www.voltaire.com <http://www.voltaire.com/>