On Tue, Mar 20, 2012 at 8:37 PM, Dan Williams <dan.j.williams@xxxxxxxxx> wrote: > On Tue, Mar 20, 2012 at 2:01 PM, Dan Williams <dan.j.williams@xxxxxxxxx> wrote: >> On Tue, Mar 20, 2012 at 1:06 PM, Bart Van Assche <bvanassche@xxxxxxx> wrote: >> [..] >>> - Fix a null pointer dereference triggered by sd during device removal. >> >> Hi Bart, >> >> Do you have a log of the backtrace in this case? I'm going to put >> this patch into our libsas/isci test environment. > > We beat on this patch pretty severely in our environment and appeared > to only trigger a hung_task timeout when our driver / libata took too > long to recovery for a 15 device unplug. So... > > Acked-by: Dan Williams <dan.j.williams@xxxxxxxxx> > Tested-by: Jacek Danecki <jacek.danecki@xxxxxxxxx> > Tested-by: Bartek Nowakowski <bartek.nowakowski@xxxxxxxxx> So, we're still able to trigger what appears to be improper handling of kblockd teardown even with this patch applied: [ 1530.709739] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 [ 1530.719307] IP: [<ffffffff8104455a>] __queue_work+0x2e5/0x332 [ 1530.726151] PGD 0 [ 1530.728807] Oops: 0000 [#1] SMP [ 1530.732860] CPU 5 [ 1530.734924] Modules linked in: isci libsas scsi_transport_sas ipv6 kvm uinput wmi sg iTCO_wdt iTCO_vendor_support i2c_i801 i2c_core igb e1000e ioatdma dca sd_mod ahci libahci libata [last unloaded: scsi_wait_scan] [ 1530.758269] [ 1530.760337] Pid: 0, comm: swapper/5 Not tainted 3.3.0-rc7-isci-183_test+ #12 Intel Corporation S2600CP/S2600CP [ 1530.772353] RIP: 0010:[<ffffffff8104455a>] [<ffffffff8104455a>] __queue_work+0x2e5/0x332 [ 1530.782294] RSP: 0018:ffff88043fd43bf0 EFLAGS: 00010046 [ 1530.788630] RAX: ffff8803fc7d2c30 RBX: ffff8803fbb6e040 RCX: 0000000000000000 [ 1530.797008] RDX: ffff8803fc7d2c38 RSI: ffff88043fd4d378 RDI: 0000000000000000 [ 1530.805384] RBP: ffff88043fd43c30 R08: 6b6b6b6b6b6b6b6b R09: 0000000000000001 [ 1530.813757] R10: 0000000000000000 R11: ffff88043fd4d358 R12: 0000000000000005 [ 1530.822132] R13: ffff88043fd56c00 R14: ffff88043fd4d340 R15: 0000000000000086 [ 1530.830503] FS: 0000000000000000(0000) GS:ffff88043fd40000(0000) knlGS:0000000000000000 [ 1530.840322] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 1530.847136] CR2: 0000000000000008 CR3: 0000000001a05000 CR4: 00000000000406e0 [ 1530.855509] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1530.863882] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 1530.872261] Process swapper/5 (pid: 0, threadinfo ffff880428cbe000, task ffff880428cc4160) [ 1530.882281] Stack: [ 1530.884913] ffff880400000000 0000000000000000 ffff88040000024b ffff8803fbb6dcd0 [ 1530.894018] ffff8803fb402bc0 ffff8803fb402bc0 0000000000000000 0000000000000001 [ 1530.903144] ffff88043fd43c40 ffffffff810445f0 ffff88043fd43c50 ffffffff81044745 [ 1530.912276] Call Trace: [ 1530.915406] <IRQ> [ 1530.918157] [<ffffffff810445f0>] queue_work_on+0x1b/0x22 [ 1530.924583] [<ffffffff81044745>] queue_work+0x1f/0x21 [ 1530.930745] [<ffffffff81247df1>] kblockd_schedule_work+0x15/0x17 [ 1530.937972] [<ffffffff812596dd>] cfq_schedule_dispatch+0x41/0x45 [ 1530.945177] [<ffffffff8125aacf>] cfq_completed_request+0x539/0x55d [ 1530.952594] [<ffffffff812436c2>] elv_completed_request+0x4a/0x4c [ 1530.959808] [<ffffffff812487dd>] __blk_put_request+0x38/0xba [ 1530.966624] [<ffffffff81248a72>] blk_finish_request+0x213/0x21f [ 1530.973740] [<ffffffff812496ec>] blk_end_bidi_request+0x42/0x5d [ 1530.980851] [<ffffffff81249743>] blk_end_request+0x10/0x12 [ 1530.987473] [<ffffffff81249781>] blk_end_request_err+0x3c/0x41 [ 1530.994507] [<ffffffff8132b244>] scsi_io_completion+0x46d/0x4cf [ 1531.001661] [<ffffffff81323e72>] scsi_finish_command+0xec/0xf5 [ 1531.008672] [<ffffffff8132b3ba>] scsi_softirq_done+0xff/0x108 [ 1531.015600] [<ffffffff8124ea08>] blk_done_softirq+0x84/0x98 [ 1531.022344] [<ffffffff81032786>] __do_softirq+0xe8/0x1e5 [ 1531.028772] [<ffffffff8148c014>] ? _raw_spin_unlock+0x2b/0x2f [ 1531.035687] [<ffffffff814941ec>] call_softirq+0x1c/0x26 [ 1531.042023] [<ffffffff81003bdb>] do_softirq+0x4b/0xa3 [ 1531.048175] [<ffffffff810324a8>] irq_exit+0x53/0xc8 [ 1531.054127] [<ffffffff81494295>] do_IRQ+0x9d/0xb4 [ 1531.059882] [<ffffffff8148c1f3>] common_interrupt+0x73/0x73 [ 1531.066620] <EOI> [ 1531.069407] [<ffffffff812d0ef2>] ? acpi_idle_enter_simple+0xee/0x12a [ 1531.077010] [<ffffffff812d0eee>] ? acpi_idle_enter_simple+0xea/0x12a [ 1531.084609] [<ffffffff8148f695>] ? notifier_call_chain+0x63/0x63 [ 1531.091835] [<ffffffff81397058>] cpuidle_idle_call+0x10b/0x1c7 [ 1531.098854] [<ffffffff81001e73>] cpu_idle+0xc0/0x10d [ 1531.104911] [<ffffffff8148585b>] start_secondary+0x277/0x279 [ 1531.111728] Code: 54 49 8b 45 08 49 8d 76 38 f6 00 10 75 05 48 89 f2 eb 40 49 8b 46 38 eb 1f 4c 8b 00 31 ff 41 f6 c0 04 74 07 4c 89 c7 40 80 e7 00 <48> 8b 7f 08 f6 07 10 74 11 48 8b 40 08 48 83 e8 08 48 8d 50 08 [ 1531.135084] RIP [<ffffffff8104455a>] __queue_work+0x2e5/0x332 [ 1531.142015] RSP <ffff88043fd43bf0> [ 1531.146301] CR2: 0000000000000008 [ 1531.150968] ---[ end trace 0711d1e925c5e6b1 ]--- -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
