syzbot
INFO: task hung in sdio_reset
Status:
upstream: reported on 2026/09/02 22:08
Reported-by: syzbot+918dfd724f02cc71b771@syzkaller.appspotmail.com
First crash: 20h14m, last: 20h14m
Sample crash report:
INFO: task kworker/1:2:971 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:2 state:D stack:22888 pid:971 ppid:2 flags:0x00004000
Workqueue: events_freezable mmc_rescan
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6701
schedule+0xbd/0x170 kernel/sched/core.c:6775
schedule_timeout+0xc1/0x2d0 kernel/time/timer.c:2144
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion+0x2c6/0x5a0 kernel/sched/completion.c:148
mmc_wait_for_req_done+0x37/0x460 drivers/mmc/core/core.c:402
mmc_wait_for_cmd+0x178/0x280 drivers/mmc/core/core.c:638
mmc_io_rw_direct_host drivers/mmc/core/sdio_ops.c:83 [inline]
sdio_reset+0x212/0x3c0 drivers/mmc/core/sdio_ops.c:215
mmc_rescan_try_freq drivers/mmc/core/core.c:2076 [inline]
mmc_rescan+0x69b/0xfb0 drivers/mmc/core/core.c:2259
process_one_work kernel/workqueue.c:2657 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
</TASK>
INFO: task kworker/1:3:5810 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:3 state:D stack:21640 pid:5810 ppid:2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6701
schedule+0xbd/0x170 kernel/sched/core.c:6775
schedule_timeout+0xc1/0x2d0 kernel/time/timer.c:2144
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion+0x2c6/0x5a0 kernel/sched/completion.c:148
__flush_work+0x92f/0xac0 kernel/workqueue.c:3475
__cancel_work_timer+0x3f8/0x560 kernel/workqueue.c:3562
__mmc_stop_host drivers/mmc/core/core.c:2308 [inline]
mmc_stop_host+0xd9/0x460 drivers/mmc/core/core.c:2313
mmc_remove_host+0x15/0x60 drivers/mmc/core/host.c:675
vub300_disconnect+0x14f/0x2e0 drivers/mmc/host/vub300.c:2380
usb_unbind_interface+0x207/0x870 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:628 [inline]
__device_release_driver drivers/base/dd.c:1351 [inline]
device_release_driver_internal+0x458/0x6f0 drivers/base/dd.c:1374
bus_remove_device+0x43b/0x520 drivers/base/bus.c:624
device_del+0x51f/0x910 drivers/base/core.c:3889
usb_disable_device+0x3ee/0x8a0 drivers/usb/core/message.c:1474
usb_disconnect+0x340/0x8a0 drivers/usb/core/hub.c:2320
hub_port_connect drivers/usb/core/hub.c:5374 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5674 [inline]
port_event drivers/usb/core/hub.c:5838 [inline]
hub_event+0x1d69/0x4a80 drivers/usb/core/hub.c:5920
process_one_work kernel/workqueue.c:2657 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
</TASK>
Showing all locks held in the system:
3 locks held by kworker/u4:0/11:
#0: ffff888017c71938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
#0: ffff888017c71938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
#1: ffffc90000107d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
#1: ffffc90000107d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
#2: ffffffff8e3d7548 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:286
1 lock held by khungtaskd/29:
#0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
2 locks held by kworker/u4:4/59:
#0: ffff8880b8e3c258 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559
#1: ffff8880b8e28a00 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline]
#1: ffff8880b8e28a00 (psi_seq){-.-.}-{0:0}, at: __schedule+0x21d3/0x4660 kernel/sched/core.c:6696
2 locks held by kworker/1:2/971:
#0: ffff888017c72138 ((wq_completion)events_freezable){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
#0: ffff888017c72138 ((wq_completion)events_freezable){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
#1: ffffc9000430fd00 ((work_completion)(&(&host->detect)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
#1: ffffc9000430fd00 ((work_completion)(&(&host->detect)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
5 locks held by kworker/1:3/5810:
#0: ffff888019accd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
#0: ffff888019accd38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
#1: ffffc900047bfd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
#1: ffffc900047bfd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
#2: ffff88802503f1d8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1094 [inline]
#2: ffff88802503f1d8 (&dev->mutex){....}-{3:3}, at: hub_event+0x188/0x4a80 drivers/usb/core/hub.c:5866
#3: ffff88807f35b1d8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1094 [inline]
#3: ffff88807f35b1d8 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0xfc/0x8a0 drivers/usb/core/hub.c:2311
#4: ffff8880223761a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1094 [inline]
#4: ffff8880223761a8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1174 [inline]
#4: ffff8880223761a8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa7/0x6f0 drivers/base/dd.c:1371
2 locks held by getty/12332:
#0: ffff88814ce330a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000d2332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217
2 locks held by kworker/0:7/843:
#0: ffff888017c72d38 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
#0: ffff888017c72d38 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
#1: ffffc9000d6ffd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
#1: ffffc9000d6ffd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
2 locks held by syz.4.10804/6119:
#0: ffffffff8e3d7548 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8e3d7548 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3514
#1: ffffffff8d137ab8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
#1: ffffffff8d137ab8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x306/0x880 kernel/rcu/tree_exp.h:1004
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
<TASK>
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf59/0xfa0 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 59 Comm: kworker/u4:4 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: bat_events batadv_tt_purge
RIP: 0010:hlock_class kernel/locking/lockdep.c:223 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4798 [inline]
RIP: 0010:__lock_acquire+0x91b/0x7d80 kernel/locking/lockdep.c:5087
Code: 97 48 c1 e8 03 48 89 44 24 20 48 c7 c0 70 c2 8c 8e 48 c1 e8 03 48 89 44 24 50 4d 89 ef 48 83 fb 31 0f 83 8d 01 00 00 4c 89 e8 <48> c1 e8 03 42 0f b6 04 00 84 c0 0f 85 97 01 00 00 41 8b 07 41 89
RSP: 0018:ffffc900015a7780 EFLAGS: 00000083
RAX: ffff88801b6d2930 RBX: 0000000000000001 RCX: ffffffff8168a3e2
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff911ef5d8
RBP: ffffc900015a79c8 R08: dffffc0000000000 R09: 1ffffffff223debb
R10: dffffc0000000000 R11: fffffbfff223debc R12: 0000000000000000
R13: ffff88801b6d2930 R14: ffffffff90bafe60 R15: ffff88801b6d2930
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9b991ef2f8 CR3: 000000000cf32000 CR4: 00000000003506e0
Call Trace:
<TASK>
lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
batadv_tt_global_purge net/batman-adv/translation-table.c:2339 [inline]
batadv_tt_purge+0x11b/0xa20 net/batman-adv/translation-table.c:3633
process_one_work kernel/workqueue.c:2657 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
</TASK>
* Struck through repros no longer work on HEAD.