Re: 4.10 lockdep: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected

From: Konstantin Khlebnikov
Date: Wed Feb 08 2017 - 08:10:58 EST


Looks like this caused by del_timer_sync() in wbt_disable_default() under irq-safe lock.

Here

void wbt_disable_default(struct request_queue *q)
{
struct rq_wb *rwb = q->rq_wb;

if (rwb && rwb->enable_state == WBT_STATE_ON_DEFAULT) {
del_timer_sync(&rwb->window_timer);
rwb->win_nsec = rwb->min_lat_nsec = 0;
wbt_update_limits(rwb);
}
}
EXPORT_SYMBOL_GPL(wbt_disable_default);


On 08.02.2017 12:51, Konstantin Khlebnikov wrote:
[ 41.715309] ======================================================
[ 41.715410] [ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ]
[ 41.715513] 4.10.0-rc7+ #2 Not tainted
[ 41.715607] ------------------------------------------------------
[ 41.715708] Starter.procman/1467 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
[ 41.715833] (((&rwb->window_timer))){+.-...}, at: [<ffffffff812fe7c5>] del_timer_sync+0x5/0x100
[ 41.715974]
and this task is already holding:
[ 41.716094] (&(&q->__queue_lock)->rlock){-.-...}, at: [<ffffffff81c192ff>] cfq_set_request+0x18f/0xd50
[ 41.716230] which would create a new lock dependency:
[ 41.716327] (&(&q->__queue_lock)->rlock){-.-...} -> (((&rwb->window_timer))){+.-...}
[ 41.716457]
but this new dependency connects a HARDIRQ-irq-safe lock:
[ 41.716582] (&(&q->__queue_lock)->rlock){-.-...}
[ 41.716585]
... which became HARDIRQ-irq-safe at:
[ 41.716801]
[ 41.716807] [<ffffffff812a457a>] __lock_acquire+0x14ba/0x3a20
[ 41.716994]
[ 41.716997] [<ffffffff812a7663>] lock_acquire+0x173/0x330
[ 41.717182]
[ 41.717186] [<ffffffff82b0a700>] _raw_spin_lock_irqsave+0x50/0x70
[ 41.717374]
[ 41.717376] [<ffffffff81c17ce4>] cfq_idle_slice_timer+0xa4/0x3b0
[ 41.717563]
[ 41.717567] [<ffffffff81307704>] __hrtimer_run_queues+0x294/0xb50
[ 41.717754]
[ 41.717756] [<ffffffff81309827>] hrtimer_interrupt+0x187/0x5e0
[ 41.717943]
[ 41.717948] [<ffffffff810f50d4>] local_apic_timer_interrupt+0x74/0xe0
[ 41.718136]
[ 41.718140] [<ffffffff82b0d576>] smp_apic_timer_interrupt+0x76/0xa0
[ 41.718327]
[ 41.718330] [<ffffffff82b0c633>] apic_timer_interrupt+0x93/0xa0
[ 41.718516]
[ 41.718520] [<ffffffff825b781b>] cpuidle_enter_state+0x11b/0x820
[ 41.718707]
[ 41.718709] [<ffffffff825b7fb7>] cpuidle_enter+0x17/0x20
[ 41.718894]
[ 41.718897] [<ffffffff81288147>] call_cpuidle+0x47/0xc0
[ 41.719082]
[ 41.719084] [<ffffffff8128854e>] do_idle+0x21e/0x2e0
[ 41.719269]
[ 41.719272] [<ffffffff81288b1d>] cpu_startup_entry+0x1d/0x20
[ 41.719458]
[ 41.719461] [<ffffffff810f110d>] start_secondary+0x29d/0x370
[ 41.719647]
[ 41.719651] [<ffffffff810001c4>] verify_cpu+0x0/0xfc
[ 41.719835]
to a HARDIRQ-irq-unsafe lock:
[ 41.719954] (((&rwb->window_timer))){+.-...}
[ 41.719957]
... which became HARDIRQ-irq-unsafe at:
[ 41.720172] ...
[ 41.720172]
[ 41.720263] [<ffffffff812a4289>] __lock_acquire+0x11c9/0x3a20
[ 41.720450]
[ 41.720452] [<ffffffff812a7663>] lock_acquire+0x173/0x330
[ 41.720638]
[ 41.720641] [<ffffffff812fe9e8>] call_timer_fn+0x118/0x520
[ 41.720827]
[ 41.720829] [<ffffffff812ff6d7>] run_timer_softirq+0x537/0x1450
[ 41.721017]
[ 41.721020] [<ffffffff82b0dc2e>] __do_softirq+0x21e/0x8a9
[ 41.721205]
[ 41.721209] [<ffffffff811b5093>] irq_exit+0x1a3/0x1d0
[ 41.721394]
[ 41.721397] [<ffffffff82b0d57b>] smp_apic_timer_interrupt+0x7b/0xa0
[ 41.721584]
[ 41.721586] [<ffffffff82b0c633>] apic_timer_interrupt+0x93/0xa0
[ 41.721772]
[ 41.721774] [<ffffffff825b781b>] cpuidle_enter_state+0x11b/0x820
[ 41.721961]
[ 41.721963] [<ffffffff825b7fb7>] cpuidle_enter+0x17/0x20
[ 41.722148]
[ 41.722151] [<ffffffff81288147>] call_cpuidle+0x47/0xc0
[ 41.722336]
[ 41.722338] [<ffffffff8128854e>] do_idle+0x21e/0x2e0
[ 41.722522]
[ 41.722524] [<ffffffff81288b1d>] cpu_startup_entry+0x1d/0x20
[ 41.722709]
[ 41.722712] [<ffffffff810f110d>] start_secondary+0x29d/0x370
[ 41.722897]
[ 41.722899] [<ffffffff810001c4>] verify_cpu+0x0/0xfc
[ 41.723083]
other info that might help us debug this:

[ 41.723320] Possible interrupt unsafe locking scenario:

[ 41.723443] CPU0 CPU1
[ 41.723538] ---- ----
[ 41.723634] lock(((&rwb->window_timer)));
[ 41.723730] local_irq_disable();
[ 41.723829] lock(&(&q->__queue_lock)->rlock);
[ 41.723931] lock(((&rwb->window_timer)));
[ 41.724033] <Interrupt>
[ 41.724124] lock(&(&q->__queue_lock)->rlock);
[ 41.724221]
*** DEADLOCK ***

[ 41.730049] 3 locks held by Starter.procman/1467:
[ 41.730144] #0: (&sig->cred_guard_mutex){+.+.+.}, at: [<ffffffff816b2c53>] prepare_bprm_creds+0x53/0x100
[ 41.730280] #1: (&type->i_mutex_dir_key#2){++++++}, at: [<ffffffff816cdb67>] path_openat+0x1317/0x2730
[ 41.730415] #2: (&(&q->__queue_lock)->rlock){-.-...}, at: [<ffffffff81c192ff>] cfq_set_request+0x18f/0xd50
[ 41.730550]
the dependencies between HARDIRQ-irq-safe lock and the holding lock:
[ 41.730701] -> (&(&q->__queue_lock)->rlock){-.-...} ops: 68816 {
[ 41.730804] IN-HARDIRQ-W at:
[ 41.730897]
[ 41.730900] [<ffffffff812a457a>] __lock_acquire+0x14ba/0x3a20
[ 41.731091]
[ 41.731093] [<ffffffff812a7663>] lock_acquire+0x173/0x330
[ 41.731283]
[ 41.731285] [<ffffffff82b0a700>] _raw_spin_lock_irqsave+0x50/0x70
[ 41.731476]
[ 41.731478] [<ffffffff81c17ce4>] cfq_idle_slice_timer+0xa4/0x3b0
[ 41.731669]
[ 41.731672] [<ffffffff81307704>] __hrtimer_run_queues+0x294/0xb50
[ 41.731862]
[ 41.731865] [<ffffffff81309827>] hrtimer_interrupt+0x187/0x5e0
[ 41.732056]
[ 41.732058] [<ffffffff810f50d4>] local_apic_timer_interrupt+0x74/0xe0
[ 41.732250]
[ 41.732253] [<ffffffff82b0d576>] smp_apic_timer_interrupt+0x76/0xa0
[ 41.732444]
[ 41.732447] [<ffffffff82b0c633>] apic_timer_interrupt+0x93/0xa0
[ 41.732637]
[ 41.732639] [<ffffffff825b781b>] cpuidle_enter_state+0x11b/0x820
[ 41.732830]
[ 41.732832] [<ffffffff825b7fb7>] cpuidle_enter+0x17/0x20
[ 41.733021]
[ 41.733023] [<ffffffff81288147>] call_cpuidle+0x47/0xc0
[ 41.733212]
[ 41.733214] [<ffffffff8128854e>] do_idle+0x21e/0x2e0
[ 41.733401]
[ 41.733404] [<ffffffff81288b1d>] cpu_startup_entry+0x1d/0x20
[ 41.733593]
[ 41.733596] [<ffffffff810f110d>] start_secondary+0x29d/0x370
[ 41.733785]
[ 41.733787] [<ffffffff810001c4>] verify_cpu+0x0/0xfc
[ 41.733975] IN-SOFTIRQ-W at:
[ 41.734068]
[ 41.734071] [<ffffffff812a4258>] __lock_acquire+0x1198/0x3a20
[ 41.734261]
[ 41.734264] [<ffffffff812a7663>] lock_acquire+0x173/0x330
[ 41.734453]
[ 41.734455] [<ffffffff82b0a700>] _raw_spin_lock_irqsave+0x50/0x70
[ 41.734646]
[ 41.734650] [<ffffffff8221f4a2>] scsi_end_request+0x272/0x5a0
[ 41.734841]
[ 41.734844] [<ffffffff8222acb5>] scsi_io_completion+0x465/0x1800
[ 41.735034]
[ 41.735037] [<ffffffff8220b353>] scsi_finish_command+0x393/0x560
[ 41.735227]
[ 41.735230] [<ffffffff82228f35>] scsi_softirq_done+0x2a5/0x350
[ 41.735420]
[ 41.735423] [<ffffffff81ba3ff8>] blk_done_softirq+0x208/0x360
[ 41.735614]
[ 41.735616] [<ffffffff82b0dc2e>] __do_softirq+0x21e/0x8a9
[ 41.735805]
[ 41.735807] [<ffffffff811b4d36>] run_ksoftirqd+0x26/0xf0
[ 41.735996]
[ 41.735999] [<ffffffff81210c14>] smpboot_thread_fn+0x3d4/0x7f0
[ 41.736190]
[ 41.736193] [<ffffffff81205d4e>] kthread+0x2ce/0x3d0
[ 41.736381]
[ 41.736383] [<ffffffff82b0aae1>] ret_from_fork+0x31/0x40
[ 41.736572] INITIAL USE at:
[ 41.736665]
[ 41.736668] [<ffffffff812a3b74>] __lock_acquire+0xab4/0x3a20
[ 41.736857]
[ 41.736860] [<ffffffff812a7663>] lock_acquire+0x173/0x330
[ 41.737049]
[ 41.737051] [<ffffffff82b09e94>] _raw_spin_lock_irq+0x44/0x60
[ 41.737240]
[ 41.737245] [<ffffffff81bfb294>] blkcg_init_queue+0xb4/0x2e0
[ 41.737526]
[ 41.737529] [<ffffffff81b7630a>] blk_alloc_queue_node+0x5ea/0x7e0
[ 41.737720]
[ 41.737722] [<ffffffff81b76513>] blk_alloc_queue+0x13/0x20
[ 41.737911]
[ 41.737914] [<ffffffff82161919>] brd_alloc+0xf9/0x590
[ 41.738103]
[ 41.738107] [<ffffffff83a40642>] brd_init+0x62/0x2ad
[ 41.738294]
[ 41.738297] [<ffffffff81002261>] do_one_initcall+0x91/0x230
[ 41.738486]
[ 41.738491] [<ffffffff8399eb3d>] kernel_init_freeable+0x44f/0x4e1
[ 41.738682]
[ 41.738685] [<ffffffff82af0ba3>] kernel_init+0x13/0x120
[ 41.738873]
[ 41.738875] [<ffffffff82b0aae1>] ret_from_fork+0x31/0x40
[ 41.739065] }
[ 41.739157] ... key at: [<ffffffff849414c0>] __key.51360+0x0/0x40
[ 41.739258] ... acquired at:
[ 41.739349]
[ 41.739352] [<ffffffff812a0a3a>] check_irq_usage+0x7a/0x180
[ 41.739538]
[ 41.739540] [<ffffffff812a559b>] __lock_acquire+0x24db/0x3a20
[ 41.739727]
[ 41.739730] [<ffffffff812a7663>] lock_acquire+0x173/0x330
[ 41.739915]
[ 41.739918] [<ffffffff812fe80e>] del_timer_sync+0x4e/0x100
[ 41.740103]
[ 41.740107] [<ffffffff81c33ee6>] wbt_disable_default+0x76/0x210
[ 41.740294]
[ 41.740296] [<ffffffff81c183c7>] check_blkcg_changed+0x3d7/0xee0
[ 41.740483]
[ 41.740485] [<ffffffff81c193f8>] cfq_set_request+0x288/0xd50
[ 41.740670]
[ 41.740674] [<ffffffff81b6b583>] elv_set_request+0x83/0xf0
[ 41.740860]
[ 41.740862] [<ffffffff81b8032d>] get_request+0x16ad/0x1dc0
[ 41.741048]
[ 41.741050] [<ffffffff81b890c5>] blk_queue_bio+0x335/0xe20
[ 41.741235]
[ 41.741238] [<ffffffff81b81ca0>] generic_make_request+0x2e0/0x730
[ 41.741425]
[ 41.741427] [<ffffffff81b82228>] submit_bio+0x138/0x4c0
[ 41.741612]
[ 41.741615] [<ffffffff817528c0>] submit_bh_wbc+0x400/0x5c0
[ 41.741801]
[ 41.741803] [<ffffffff81754566>] ll_rw_block+0xc6/0x160
[ 41.741989]
[ 41.741992] [<ffffffff81890650>] ext4_find_entry+0xc60/0x1230
[ 41.742179]
[ 41.742181] [<ffffffff81891ed2>] ext4_lookup+0x112/0x770
[ 41.742366]
[ 41.742368] [<ffffffff816c3ee1>] lookup_open+0xd41/0x1520
[ 41.742553]
[ 41.742555] [<ffffffff816cdb8a>] path_openat+0x133a/0x2730
[ 41.742741]
[ 41.742743] [<ffffffff816d25b5>] do_filp_open+0x175/0x230
[ 41.742928]
[ 41.742931] [<ffffffff816ad999>] do_open_execat+0xb9/0x480
[ 41.743116]
[ 41.743119] [<ffffffff816b3351>] do_execveat_common.isra.39+0x651/0x1ec0
[ 41.743308]
[ 41.743310] [<ffffffff816b546a>] SyS_execve+0x3a/0x50
[ 41.743495]
[ 41.743498] [<ffffffff8100768d>] do_syscall_64+0x18d/0x450
[ 41.743683]
[ 41.743686] [<ffffffff82b0a90d>] return_from_SYSCALL_64+0x0/0x7a

[ 41.743961]
the dependencies between the lock to be acquired
[ 41.743962] and HARDIRQ-irq-unsafe lock:
[ 41.744181] -> (((&rwb->window_timer))){+.-...} ops: 362 {
[ 41.744282] HARDIRQ-ON-W at:
[ 41.744375]
[ 41.744378] [<ffffffff812a4289>] __lock_acquire+0x11c9/0x3a20
[ 41.744568]
[ 41.744570] [<ffffffff812a7663>] lock_acquire+0x173/0x330
[ 41.744760]
[ 41.744762] [<ffffffff812fe9e8>] call_timer_fn+0x118/0x520
[ 41.744951]
[ 41.744954] [<ffffffff812ff6d7>] run_timer_softirq+0x537/0x1450
[ 41.745144]
[ 41.745147] [<ffffffff82b0dc2e>] __do_softirq+0x21e/0x8a9
[ 41.745336]
[ 41.745338] [<ffffffff811b5093>] irq_exit+0x1a3/0x1d0
[ 41.745527]
[ 41.745529] [<ffffffff82b0d57b>] smp_apic_timer_interrupt+0x7b/0xa0
[ 41.745720]
[ 41.745723] [<ffffffff82b0c633>] apic_timer_interrupt+0x93/0xa0
[ 41.745913]
[ 41.745915] [<ffffffff825b781b>] cpuidle_enter_state+0x11b/0x820
[ 41.746106]
[ 41.746108] [<ffffffff825b7fb7>] cpuidle_enter+0x17/0x20
[ 41.746297]
[ 41.746299] [<ffffffff81288147>] call_cpuidle+0x47/0xc0
[ 41.746488]
[ 41.746490] [<ffffffff8128854e>] do_idle+0x21e/0x2e0
[ 41.746678]
[ 41.746680] [<ffffffff81288b1d>] cpu_startup_entry+0x1d/0x20
[ 41.746870]
[ 41.746872] [<ffffffff810f110d>] start_secondary+0x29d/0x370
[ 41.752819]
[ 41.752821] [<ffffffff810001c4>] verify_cpu+0x0/0xfc
[ 41.753009] IN-SOFTIRQ-W at:
[ 41.753102]
[ 41.753105] [<ffffffff812a4258>] __lock_acquire+0x1198/0x3a20
[ 41.753295]
[ 41.753297] [<ffffffff812a7663>] lock_acquire+0x173/0x330
[ 41.753487]
[ 41.753489] [<ffffffff812fe9e8>] call_timer_fn+0x118/0x520
[ 41.753679]
[ 41.753681] [<ffffffff812ff6d7>] run_timer_softirq+0x537/0x1450
[ 41.753872]
[ 41.753874] [<ffffffff82b0dc2e>] __do_softirq+0x21e/0x8a9
[ 41.754063]
[ 41.754065] [<ffffffff811b5093>] irq_exit+0x1a3/0x1d0
[ 41.754254]
[ 41.754256] [<ffffffff82b0d57b>] smp_apic_timer_interrupt+0x7b/0xa0
[ 41.754447]
[ 41.754450] [<ffffffff82b0c633>] apic_timer_interrupt+0x93/0xa0
[ 41.754640]
[ 41.754642] [<ffffffff825b781b>] cpuidle_enter_state+0x11b/0x820
[ 41.754833]
[ 41.754835] [<ffffffff825b7fb7>] cpuidle_enter+0x17/0x20
[ 41.755024]
[ 41.755026] [<ffffffff81288147>] call_cpuidle+0x47/0xc0
[ 41.755214]
[ 41.755216] [<ffffffff8128854e>] do_idle+0x21e/0x2e0
[ 41.755404]
[ 41.755406] [<ffffffff81288b1d>] cpu_startup_entry+0x1d/0x20
[ 41.755596]
[ 41.755598] [<ffffffff810f110d>] start_secondary+0x29d/0x370
[ 41.755788]
[ 41.755790] [<ffffffff810001c4>] verify_cpu+0x0/0xfc
[ 41.755978] INITIAL USE at:
[ 41.756070]
[ 41.756073] [<ffffffff812a3b74>] __lock_acquire+0xab4/0x3a20
[ 41.756262]
[ 41.756265] [<ffffffff812a7663>] lock_acquire+0x173/0x330
[ 41.756454]
[ 41.756456] [<ffffffff812fe9e8>] call_timer_fn+0x118/0x520
[ 41.756645]
[ 41.756648] [<ffffffff812ff6d7>] run_timer_softirq+0x537/0x1450
[ 41.756838]
[ 41.756841] [<ffffffff82b0dc2e>] __do_softirq+0x21e/0x8a9
[ 41.757029]
[ 41.757031] [<ffffffff811b5093>] irq_exit+0x1a3/0x1d0
[ 41.757220]
[ 41.757222] [<ffffffff82b0d57b>] smp_apic_timer_interrupt+0x7b/0xa0
[ 41.757413]
[ 41.757416] [<ffffffff82b0c633>] apic_timer_interrupt+0x93/0xa0
[ 41.757606]
[ 41.757608] [<ffffffff825b781b>] cpuidle_enter_state+0x11b/0x820
[ 41.757798]
[ 41.757800] [<ffffffff825b7fb7>] cpuidle_enter+0x17/0x20
[ 41.757989]
[ 41.757991] [<ffffffff81288147>] call_cpuidle+0x47/0xc0
[ 41.758180]
[ 41.758182] [<ffffffff8128854e>] do_idle+0x21e/0x2e0
[ 41.758371]
[ 41.758373] [<ffffffff81288b1d>] cpu_startup_entry+0x1d/0x20
[ 41.758562]
[ 41.758565] [<ffffffff810f110d>] start_secondary+0x29d/0x370
[ 41.758754]
[ 41.758756] [<ffffffff810001c4>] verify_cpu+0x0/0xfc
[ 41.758943] }
[ 41.759034] ... key at: [<ffffffff849430c0>] __key.42825+0x0/0x40
[ 41.759135] ... acquired at:
[ 41.759227]
[ 41.759229] [<ffffffff812a0a3a>] check_irq_usage+0x7a/0x180
[ 41.759415]
[ 41.759418] [<ffffffff812a559b>] __lock_acquire+0x24db/0x3a20
[ 41.759604]
[ 41.759607] [<ffffffff812a7663>] lock_acquire+0x173/0x330
[ 41.759792]
[ 41.759795] [<ffffffff812fe80e>] del_timer_sync+0x4e/0x100
[ 41.759981]
[ 41.759983] [<ffffffff81c33ee6>] wbt_disable_default+0x76/0x210
[ 41.760170]
[ 41.760172] [<ffffffff81c183c7>] check_blkcg_changed+0x3d7/0xee0
[ 41.760359]
[ 41.760361] [<ffffffff81c193f8>] cfq_set_request+0x288/0xd50
[ 41.760547]
[ 41.760550] [<ffffffff81b6b583>] elv_set_request+0x83/0xf0
[ 41.760735]
[ 41.760737] [<ffffffff81b8032d>] get_request+0x16ad/0x1dc0
[ 41.760923]
[ 41.760925] [<ffffffff81b890c5>] blk_queue_bio+0x335/0xe20
[ 41.761111]
[ 41.761113] [<ffffffff81b81ca0>] generic_make_request+0x2e0/0x730
[ 41.761300]
[ 41.761302] [<ffffffff81b82228>] submit_bio+0x138/0x4c0
[ 41.761487]
[ 41.761490] [<ffffffff817528c0>] submit_bh_wbc+0x400/0x5c0
[ 41.761675]
[ 41.761678] [<ffffffff81754566>] ll_rw_block+0xc6/0x160
[ 41.761863]
[ 41.761865] [<ffffffff81890650>] ext4_find_entry+0xc60/0x1230
[ 41.762052]
[ 41.762054] [<ffffffff81891ed2>] ext4_lookup+0x112/0x770
[ 41.762239]
[ 41.762241] [<ffffffff816c3ee1>] lookup_open+0xd41/0x1520
[ 41.762427]
[ 41.762429] [<ffffffff816cdb8a>] path_openat+0x133a/0x2730
[ 41.762614]
[ 41.762616] [<ffffffff816d25b5>] do_filp_open+0x175/0x230
[ 41.762802]
[ 41.762805] [<ffffffff816ad999>] do_open_execat+0xb9/0x480
[ 41.762990]
[ 41.762993] [<ffffffff816b3351>] do_execveat_common.isra.39+0x651/0x1ec0
[ 41.763182]
[ 41.763184] [<ffffffff816b546a>] SyS_execve+0x3a/0x50
[ 41.763369]
[ 41.763371] [<ffffffff8100768d>] do_syscall_64+0x18d/0x450
[ 41.763557]
[ 41.763559] [<ffffffff82b0a90d>] return_from_SYSCALL_64+0x0/0x7a

[ 41.763834]
stack backtrace:
[ 41.763952] CPU: 20 PID: 1467 Comm: Starter.procman Not tainted 4.10.0-rc7+ #2
[ 41.764076] Hardware name: Supermicro X9DRW/X9DRW, BIOS 3.0c 10/30/2014
[ 41.764178] Call Trace:
[ 41.764272] dump_stack+0x85/0xc4
[ 41.764367] check_usage+0xb80/0xdd0
[ 41.764463] ? check_usage_backwards+0x2f0/0x2f0
[ 41.764562] ? unwind_next_frame+0x1f3/0x9d0
[ 41.764659] ? entry_SYSCALL64_slow_path+0x25/0x25
[ 41.764756] ? unwind_get_return_address+0x17e/0x260
[ 41.764854] ? __unwind_start+0x390/0x390
[ 41.764950] ? __unwind_start+0x1d0/0x390
[ 41.765046] check_irq_usage+0x7a/0x180
[ 41.765142] __lock_acquire+0x24db/0x3a20
[ 41.765239] ? debug_check_no_locks_freed+0x290/0x290
[ 41.765338] ? debug_check_no_locks_freed+0x290/0x290
[ 41.765439] ? alloc_debug_processing+0x73/0x1b0
[ 41.765537] lock_acquire+0x173/0x330
[ 41.765632] ? del_timer_sync+0x5/0x100
[ 41.765728] del_timer_sync+0x4e/0x100
[ 41.765824] ? del_timer_sync+0x5/0x100
[ 41.766008] wbt_disable_default+0x76/0x210
[ 41.766104] check_blkcg_changed+0x3d7/0xee0
[ 41.766200] ? check_blkcg_changed+0xbe/0xee0
[ 41.766296] ? cfq_idle_slice_timer+0x3b0/0x3b0
[ 41.766394] ? cfq_set_request+0x18f/0xd50
[ 41.766490] cfq_set_request+0x288/0xd50
[ 41.766587] ? debug_lockdep_rcu_enabled+0x77/0x90
[ 41.766684] ? cfq_exit_icq+0x170/0x170
[ 41.766780] ? mark_held_locks+0xc8/0x120
[ 41.766875] ? _raw_spin_unlock_irq+0x2c/0x40
[ 41.766972] ? trace_hardirqs_on_caller+0x3fe/0x580
[ 41.767070] ? trace_hardirqs_on+0xd/0x10
[ 41.767165] ? _raw_spin_unlock_irq+0x2c/0x40
[ 41.767263] ? ioc_create_icq+0x403/0x6a0
[ 41.767359] elv_set_request+0x83/0xf0
[ 41.767454] get_request+0x16ad/0x1dc0
[ 41.767549] ? get_request+0xb0/0x1dc0
[ 41.767645] ? trace_event_raw_event_block_rq_with_error+0x680/0x680
[ 41.767747] ? wake_atomic_t_function+0x2a0/0x2a0
[ 41.767844] ? elv_merge+0x25e/0x300
[ 41.767939] blk_queue_bio+0x335/0xe20
[ 41.768034] ? blk_flush_plug_list+0x920/0x920
[ 41.768131] ? blk_exit_rl+0x40/0x40
[ 41.768226] ? generic_make_request+0x365/0x730
[ 41.768323] generic_make_request+0x2e0/0x730
[ 41.768419] ? generic_make_request+0x2d3/0x730
[ 41.768516] ? blk_queue_enter+0x510/0x510
[ 41.768612] ? __find_get_block+0x5b8/0x800
[ 41.768709] submit_bio+0x138/0x4c0
[ 41.768803] ? __getblk_gfp+0x14a/0x6f0
[ 41.768899] ? do_execveat_common.isra.39+0x651/0x1ec0
[ 41.768997] ? generic_make_request+0x730/0x730
[ 41.769095] submit_bh_wbc+0x400/0x5c0
[ 41.769190] ll_rw_block+0xc6/0x160
[ 41.769285] ext4_find_entry+0xc60/0x1230
[ 41.769381] ? ext4_search_dir+0x4b0/0x4b0
[ 41.769478] ? d_alloc_parallel+0x595/0x1550
[ 41.769574] ? d_alloc_parallel+0x5b4/0x1550
[ 41.769670] ? lookup_open+0x430/0x1520
[ 41.769766] ? __d_lookup+0x1aa/0x5e0
[ 41.775578] ext4_lookup+0x112/0x770
[ 41.775673] ? __d_lookup+0x1c9/0x5e0
[ 41.775767] ? __d_lookup+0x3e/0x5e0
[ 41.775862] ? ext4_cross_rename+0x11a0/0x11a0
[ 41.775958] ? ext4_cross_rename+0x11a0/0x11a0
[ 41.776055] lookup_open+0xd41/0x1520
[ 41.776150] ? vfs_link+0xa90/0xa90
[ 41.776245] path_openat+0x133a/0x2730
[ 41.776340] ? path_lookupat+0x3d0/0x3d0
[ 41.776435] ? save_stack+0xb5/0xd0
[ 41.776530] ? save_stack_trace+0x1b/0x20
[ 41.776625] ? save_stack+0x46/0xd0
[ 41.776718] ? kasan_kmalloc+0xad/0xe0
[ 41.776813] ? kasan_slab_alloc+0x12/0x20
[ 41.776908] ? kmem_cache_alloc+0xcc/0x2b0
[ 41.777005] ? prepare_creds+0x26/0x2b0
[ 41.777099] ? prepare_exec_creds+0x11/0xe0
[ 41.777195] ? prepare_bprm_creds+0x5e/0x100
[ 41.777291] ? do_execveat_common.isra.39+0x2a1/0x1ec0
[ 41.777389] ? SyS_execve+0x3a/0x50
[ 41.777483] ? do_syscall_64+0x18d/0x450
[ 41.777578] ? entry_SYSCALL64_slow_path+0x25/0x25
[ 41.777675] do_filp_open+0x175/0x230
[ 41.777770] ? may_open_dev+0xc0/0xc0
[ 41.777865] ? __slab_alloc+0x5e/0x90
[ 41.777961] ? debug_lockdep_rcu_enabled+0x77/0x90
[ 41.778058] do_open_execat+0xb9/0x480
[ 41.778153] ? setup_arg_pages+0x760/0x760
[ 41.778250] do_execveat_common.isra.39+0x651/0x1ec0
[ 41.778347] ? do_execveat_common.isra.39+0x38a/0x1ec0
[ 41.778446] ? kasan_check_write+0x14/0x20
[ 41.778541] ? rcu_read_lock_sched_held+0x80/0x130
[ 41.778639] ? prepare_bprm_creds+0x100/0x100
[ 41.778735] ? getname_flags+0x102/0x510
[ 41.778831] SyS_execve+0x3a/0x50
[ 41.778925] ? ptregs_sys_vfork+0x10/0x10
[ 41.779020] do_syscall_64+0x18d/0x450
[ 41.779115] ? setup_new_exec+0x7e0/0x7e0
[ 41.779222] entry_SYSCALL64_slow_path+0x25/0x25
[ 41.779327] RIP: 0033:0x7f50f1d88bc7
[ 41.779420] RSP: 002b:00007ffcfc1d7b98 EFLAGS: 00000202 ORIG_RAX: 000000000000003b
[ 41.779546] RAX: ffffffffffffffda RBX: 00007f50f336ef80 RCX: 00007f50f1d88bc7
[ 41.779649] RDX: 0000000001a1fdd0 RSI: 0000000001a7af70 RDI: 0000000001a7aef0
[ 41.779751] RBP: 0000000000000009 R08: 0000000000000000 R09: 000000000000000f
[ 41.779854] R10: 0000000000000598 R11: 0000000000000202 R12: 0000000001a7af70
[ 41.779956] R13: 0000000000000001 R14: 00007f50eac83cb0 R15: 0000000001a7af70