INFO: task syz.0.1423:11924 blocked for more than 143 seconds.
Not tainted 6.15.0-rc2-syzkaller-00400-g3088d26962e8 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1423 state:D stack:26696 pid:11924 tgid:11923 ppid:5823 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
bit_wait+0x15/0xe0 kernel/sched/wait_bit.c:237
__wait_on_bit+0x62/0x180 kernel/sched/wait_bit.c:49
out_of_line_wait_on_bit+0xd9/0x110 kernel/sched/wait_bit.c:64
wait_on_bit include/linux/wait_bit.h:77 [inline]
netfs_unbuffered_write_iter_locked+0xaa7/0xd40 fs/netfs/direct_write.c:108
netfs_unbuffered_write_iter+0x414/0x6d0 fs/netfs/direct_write.c:195
v9fs_file_write_iter+0xbf/0x100 fs/9p/vfs_file.c:404
new_sync_write fs/read_write.c:591 [inline]
vfs_write+0x5ba/0x1180 fs/read_write.c:684
ksys_write+0x12a/0x240 fs/read_write.c:736
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f439618e169
RSP: 002b:00007f43970d4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f43963b5fa0 RCX: 00007f439618e169
RDX: 0000000000007fec RSI: 0000200000001940 RDI: 0000000000000007
RBP: 00007f4396210a68 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f43963b5fa0 R15: 00007ffc35d7cae8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764
5 locks held by kworker/u8:2/36:
3 locks held by kworker/u8:5/83:
#0: ffff88801b481148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc900015b7d18 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
#2: ffff888028508768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6092 [inline]
#2: ffff888028508768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0x99/0x550 net/wireless/core.c:421
2 locks held by pvrusb2-context/2327:
#0: ffff88807e3e4188 (&hdw->big_lock_mutex){+.+.}-{4:4}, at: pvr2_hdw_initialize+0xb6/0x4510 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2326
#1: ffffffff8e273f90 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0xa9/0x250 kernel/umh.c:214
2 locks held by getty/5580:
#0: ffff8880328840a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
6 locks held by kworker/0:4/5873:
#0: ffff888144ec5948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc900041dfd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
#2: ffff888029809198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#2: ffff888029809198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4fa0 drivers/usb/core/hub.c:5859
#3: ffff88804263f198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#3: ffff88804263f198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x920 drivers/usb/core/hub.c:2307
#4: ffff88801bb3d160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#4: ffff88801bb3d160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline]
#4: ffff88801bb3d160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1293
#5: ffff88807e3e4188 (&hdw->big_lock_mutex){+.+.}-{4:4}, at: pvr2_hdw_disconnect+0x8a/0x630 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2710
2 locks held by kworker/u8:8/5924:
#0: ffff8880b8439dd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:613 [inline]
#0: ffff8880b8439dd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:598
#1: ffff8880b8423c48 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2c1/0x8e0 kernel/sched/psi.c:987
2 locks held by kworker/u8:9/6126:
#0: ffff88801b481148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc90004b5fd18 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
3 locks held by syz.0.1423/11924:
#0: ffff8880591ca0f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2a2/0x370 fs/file.c:1213
#1: ffff888031c58420 (sb_writers#18){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736
#2: ffff888073bc8148 (&sb->s_type->i_mutex_key#24){++++}-{4:4}, at: netfs_start_io_direct+0x116/0x260 fs/netfs/locking.c:188
4 locks held by udevd/13227:
#0: ffff88802ad302f0 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182
#1: ffff888031822c88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154
#2: ffff8880340ff698 (kn->active#25){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155
#3: ffff88804263f198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:927 [inline]
#3: ffff88804263f198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
3 locks held by syz.3.1776/13466:
#0: ffff8880217090a0 (&tty->ldisc_sem){++++}-{0:0}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:289 [inline]
#0: ffff8880217090a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:335 [inline]
#0: ffff8880217090a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline]
#0: ffff8880217090a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_release+0x153/0x2e0 drivers/tty/tty_ldisc.c:780
#1: ffff88802170e0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: __tty_ldisc_lock_nested drivers/tty/tty_ldisc.c:295 [inline]
#1: ffff88802170e0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:337 [inline]
#1: ffff88802170e0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline]
#1: ffff88802170e0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_release+0x17d/0x2e0 drivers/tty/tty_ldisc.c:780
#2: ffffffff8e3ca9c0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3774
1 lock held by syz.1.1779/13473:
#0: ffffffff9012ab68 (rtnl_mutex){+.+.}-{4:4}, at: ppp_release+0x167/0x230 drivers/net/ppp/ppp_generic.c:420
2 locks held by syz.1.1779/13478:
#0: ffffffff9012ab68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff9012ab68 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x371/0xe90 net/core/rtnetlink.c:6961
#1: ffffffff8e3caaf8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:336
2 locks held by syz.4.1775/13479:
2 locks held by syz.5.1778/13484:
#0: ffff88805ab476d0 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0x150/0x990 net/netlink/af_netlink.c:2388
#1: ffffffff9012ab68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff9012ab68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x18f/0x1f0 net/core/rtnetlink.c:6823
1 lock held by syz.5.1778/13485:
#0: ffffffff9012ab68 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x255/0x4740 drivers/net/tun.c:3038
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller-00400-g3088d26962e8 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0xf70/0x12c0 kernel/hung_task.c:437
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
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: 0 Comm: swapper/1 Not tainted 6.15.0-rc2-syzkaller-00400-g3088d26962e8 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x70 kernel/kcov.c:217
Code: 90 eb 11 65 8b 05 89 90 eb 11 a9 00 01 ff 00 74 1d f6 c4 01 74 43 a9 00 00 0f 00 75 3c a9 00 00 f0 00 75 35 8b 82 3c 16 00 00 <85> c0 74 2b 8b 82 18 16 00 00 83 f8 02 75 20 48 8b 8a 20 16 00 00
RSP: 0018:ffffc90000a08b70 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 000000000abcc771 RCX: ffffffff8980dcdd
RDX: ffff88801dad2440 RSI: ffffffff8980dca2 RDI: 0000000000000005
RBP: 00004189374bc6a7 R08: 0000000000000005 R09: 00000000000f4240
R10: 00000000000003e8 R11: 0000000000000000 R12: 0000000000001388
R13: 0000000000000004 R14: 000000000112e0be R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124ab2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fab2937fab8 CR3: 0000000029b62000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
pie_calculate_probability+0x272/0x850 net/sched/sch_pie.c:352
fq_pie_timer+0x21e/0x5b0 net/sched/sch_fq_pie.c:400
call_timer_fn+0x197/0x620 kernel/time/timer.c:1789
expire_timers kernel/time/timer.c:1840 [inline]
__run_timers+0x6ef/0x960 kernel/time/timer.c:2414
__run_timer_base kernel/time/timer.c:2426 [inline]
__run_timer_base kernel/time/timer.c:2418 [inline]
run_timer_base+0x114/0x190 kernel/time/timer.c:2435
run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2445
handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:81
Code: 45 5d 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d b3 5a 17 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df8 EFLAGS: 000002c6
RAX: 00000000048b1a59 RBX: 0000000000000001 RCX: ffffffff8b729419
RDX: 0000000000000000 RSI: ffffffff8dbef7a7 RDI: ffffffff8bf46440
RBP: ffffed1003b5a488 R08: 0000000000000001 R09: ffffed10170a65bd
R10: ffff8880b8532deb R11: 0000000000000000 R12: 0000000000000001
R13: ffff88801dad2440 R14: ffffffff90864610 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:748
default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117
cpuidle_idle_call kernel/sched/idle.c:185 [inline]
do_idle+0x391/0x510 kernel/sched/idle.c:325
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423
start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x148
vkms_vblank_simulate: vblank timer overrun