INFO: task syz-executor:30557 blocked for more than 143 seconds.
Tainted: G U syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:24216 pid:30557 tgid:30557 ppid:1 task_flags:0x480140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121
__debugfs_file_removed fs/debugfs/inode.c:769 [inline]
remove_one+0x312/0x420 fs/debugfs/inode.c:776
__simple_recursive_removal+0x15b/0x610 fs/libfs.c:631
debugfs_remove+0x5d/0x80 fs/debugfs/inode.c:799
nsim_dev_health_exit+0x3b/0xe0 drivers/net/netdevsim/health.c:227
nsim_dev_reload_destroy+0x144/0x4d0 drivers/net/netdevsim/dev.c:1710
nsim_drv_remove+0x52/0x1d0 drivers/net/netdevsim/dev.c:1722
device_remove+0xcb/0x170 drivers/base/dd.c:569
__device_release_driver drivers/base/dd.c:1274 [inline]
device_release_driver_internal+0x44b/0x620 drivers/base/dd.c:1297
bus_remove_device+0x22f/0x420 drivers/base/bus.c:579
device_del+0x396/0x9f0 drivers/base/core.c:3878
device_unregister+0x1d/0xc0 drivers/base/core.c:3919
nsim_bus_dev_del drivers/net/netdevsim/bus.c:483 [inline]
del_device_store+0x355/0x4a0 drivers/net/netdevsim/bus.c:244
bus_attr_store+0x74/0xb0 drivers/base/bus.c:172
sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
kernfs_fop_write_iter+0x3af/0x570 fs/kernfs/file.c:352
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x7d0/0x11d0 fs/read_write.c:686
ksys_write+0x12a/0x250 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7a29b8d65f
RSP: 002b:00007ffd818417a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f7a29b8d65f
RDX: 0000000000000001 RSI: 00007ffd818417f0 RDI: 0000000000000005
RBP: 00007f7a29c130c1 R08: 0000000000000000 R09: 00007ffd818415f7
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffd818417f0 R14: 00007f7a2a904620 R15: 0000000000000003
INFO: task syz.5.4852:30744 blocked for more than 143 seconds.
Tainted: G U syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.4852 state:D stack:27304 pid:30744 tgid:30743 ppid:29018 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760
devlink_health_report+0x3ba/0x9c0 net/devlink/health.c:627
nsim_dev_health_break_write+0x166/0x210 drivers/net/netdevsim/health.c:162
full_proxy_write+0x131/0x1a0 fs/debugfs/file.c:388
vfs_write+0x2a0/0x11d0 fs/read_write.c:684
ksys_write+0x12a/0x250 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4381f8eba9
RSP: 002b:00007f4382eec038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f43821d5fa0 RCX: 00007f4381f8eba9
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007f4382011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f43821d6038 R14: 00007f43821d5fa0 R15: 00007ffe977dfb08
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5c1420 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c1420 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c1420 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
1 lock held by syz.3.2761/19918:
2 locks held by getty/25620:
#0: ffff8880351060a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900031c52f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
7 locks held by syz-executor/30557:
#0: ffff8880353e4428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738
#1: ffff88807cbebc88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x570 fs/kernfs/file.c:343
#2: ffff8880273b8788 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff8880273b8788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2ff/0x570 fs/kernfs/file.c:344
#3: ffffffff8f8f7508 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234
#4: ffff88802a19d0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
#4: ffff88802a19d0e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1096 [inline]
#4: ffff88802a19d0e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1294
#5: ffff88802a19e250 (&devlink->lock_key#10){+.+.}-{4:4}, at: nsim_drv_remove+0x4a/0x1d0 drivers/net/netdevsim/dev.c:1721
#6: ffff88805d6f5fd8 (&sb->s_type->i_mutex_key#3/2){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:915 [inline]
#6: ffff88805d6f5fd8 (&sb->s_type->i_mutex_key#3/2){+.+.}-{4:4}, at: __simple_recursive_removal+0x354/0x610 fs/libfs.c:627
3 locks held by syz.5.4852/30744:
#0: ffff88807d45b7b8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2a2/0x370 fs/file.c:1232
#1: ffff8881412d2428 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738
#2: ffff88802a19e250 (&devlink->lock_key#10){+.+.}-{4:4}, at: devlink_health_report+0x3ba/0x9c0 net/devlink/health.c:627
4 locks held by syz-executor/30935:
#0: ffff8880353e4428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738
#1: ffff8880874a8888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x570 fs/kernfs/file.c:343
#2: ffff8880273b8788 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff8880273b8788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2ff/0x570 fs/kernfs/file.c:344
#3: ffffffff8f8f7508 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234
4 locks held by syz-executor/30980:
#0: ffff8880353e4428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738
#1: ffff888033257888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x570 fs/kernfs/file.c:343
#2: ffff8880273b8788 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff8880273b8788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2ff/0x570 fs/kernfs/file.c:344
#3: ffffffff8f8f7508 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234
4 locks held by syz-executor/30991:
#0: ffff8880353e4428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738
#1: ffff88805ba49488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x570 fs/kernfs/file.c:343
#2: ffff8880273b8788 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff8880273b8788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2ff/0x570 fs/kernfs/file.c:344
#3: ffffffff8f8f7508 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234
4 locks held by syz-executor/31006:
#0: ffff8880353e4428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738
#1: ffff88807c5afc88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x570 fs/kernfs/file.c:343
#2: ffff8880273b8788 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff8880273b8788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2ff/0x570 fs/kernfs/file.c:344
#3: ffffffff8f8f7508 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234
4 locks held by syz-executor/31018:
#0: ffff8880353e4428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738
#1: ffff88805b1a0488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x570 fs/kernfs/file.c:343
#2: ffff8880273b8788 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff8880273b8788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2ff/0x570 fs/kernfs/file.c:344
#3: ffffffff8f8f7508 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U syzkaller #0 PREEMPT(full)
Tainted: [U]=USER
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf0e/0x1260 kernel/hung_task.c:491
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x56d/0x730 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 19173 Comm: kworker/1:3 Tainted: G U syzkaller #0 PREEMPT(full)
Tainted: [U]=USER
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events nsim_dev_hwstats_traffic_work
RIP: 0010:trace_irq_enable.constprop.0+0x37/0x120 include/trace/events/preemptirq.h:40
Code: 07 0f 87 f3 00 00 00 89 db be 08 00 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 90 a9 ab 90 e8 21 8a 5d 00 48 0f a3 1d e9 ba e8 0e <0f> 82 92 00 00 00 5b 5d c3 cc cc cc cc 48 89 fb 65 8b 05 76 71 13
RSP: 0018:ffffc90003b8fc08 EFLAGS: 00000047
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff81c2ee9f
RDX: fffffbfff2157533 RSI: 0000000000000008 RDI: ffffffff90aba990
RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2157532
R10: ffffffff90aba997 R11: ffffffff9b08ee40 R12: 0000000000000001
R13: 0000000000000008 R14: ffff88801b880c00 R15: 000000000000000a
FS: 0000000000000000(0000) GS:ffff8881247ba000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055cdce78b168 CR3: 0000000055654000 CR4: 00000000003526f0
Call Trace:
trace_hardirqs_on+0x26/0x40 kernel/trace/trace_preemptirq.c:73
queue_delayed_work_on+0x12f/0x200 kernel/workqueue.c:2563
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x56d/0x730 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245