INFO: task syz.5.2411:16869 blocked for more than 143 seconds.
Tainted: G L Y syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.2411 state:D stack:25464 pid:16869 tgid:16868 ppid:9607 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5535 [inline]
__schedule+0x1b47/0x5c60 kernel/sched/core.c:7305
__schedule_loop kernel/sched/core.c:7382 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7397
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7454
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
write_versions+0x95/0xe30 fs/nfsd/nfsctl.c:715
nfsctl_transaction_write+0x10f/0x160 fs/nfsd/nfsctl.c:117
vfs_write+0x296/0xba0 fs/read_write.c:685
ksys_write+0x150/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe82559e159
RSP: 002b:00007fe82651f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fe825825fa0 RCX: 00007fe82559e159
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 00007fe82563506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe825826038 R14: 00007fe825825fa0 R15: 00007fff29cafc38
INFO: task syz.5.2411:16880 blocked for more than 143 seconds.
Tainted: G L Y syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.2411 state:D stack:28808 pid:16880 tgid:16868 ppid:9607 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5535 [inline]
__schedule+0x1b47/0x5c60 kernel/sched/core.c:7305
__schedule_loop kernel/sched/core.c:7382 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7397
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7454
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
fdget_pos+0x118/0x160 fs/file.c:1408
class_fd_pos_constructor include/linux/file.h:86 [inline]
ksys_write+0x79/0x270 fs/read_write.c:730
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe82559e159
RSP: 002b:00007fe826438028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fe825826630 RCX: 00007fe82559e159
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 00007fe82563506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe8258266c8 R14: 00007fe825826630 R15: 00007fff29cafc38
Showing all locks held in the system:
locks held by khungtaskd/33: 1, last CPU#0:
#0: ffffffff8f15c2a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8f15c2a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8f15c2a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by getty/5369: 2, on CPU#1:
#0: ffff8880328260a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by kworker/0:6/5791: 3, on CPU#0:
#0: ffff88813fe0ad48 ((wq_completion)events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88813fe0ad48 ((wq_completion)events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88813fe0ad48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#0: ffff88813fe0ad48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#1: ffffc90004e6fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90004e6fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90004e6fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#1: ffffc90004e6fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#2: ffff88807b1cf258 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1fd/0x3b0 drivers/net/netdevsim/fib.c:1490
locks held by kworker/u8:35/10557: 2, on CPU#0:
#0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#1: ffffc90003447c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90003447c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90003447c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#1: ffffc90003447c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
locks held by kworker/u8:57/10579: 3, last CPU#0:
#0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#0: ffff88813fe4c148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#1: ffffc90004dafc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90004dafc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90004dafc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#1: ffffc90004dafc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#2: ffff8880869a0800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6908 [inline]
#2: ffff8880869a0800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x420 net/wireless/core.c:550
locks held by syz.6.2252/15859: 2, on CPU#0:
#0: ffffffff906e5fc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8f49f8e0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2b9/0xc30 fs/nfsd/nfsctl.c:1712
locks held by syz.5.2411/16869: 3, on CPU#1:
#0: ffff888033d7cd30 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x118/0x160 fs/file.c:1408
#1: ffff888033bb0460 (sb_writers#27){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2753 [inline]
#1: ffff888033bb0460 (sb_writers#27){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
#2: ffffffff8f49f8e0 (nfsd_mutex){+.+.}-{4:4}, at: write_versions+0x95/0xe30 fs/nfsd/nfsctl.c:715
locks held by syz.5.2411/16880: 1, on CPU#1:
#0: ffff888033d7cd30 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x118/0x160 fs/file.c:1408
locks held by syz.0.2574/17896: 3, on CPU#1:
#0: ffff88802bae82b0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x118/0x160 fs/file.c:1408
#1: ffff88808132e460 (sb_writers#27){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2753 [inline]
#1: ffff88808132e460 (sb_writers#27){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
#2: ffffffff8f49f8e0 (nfsd_mutex){+.+.}-{4:4}, at: write_ports+0xb5/0xd10 fs/nfsd/nfsctl.c:874
locks held by syz.2.2657/18757: 2, on CPU#0:
#0: ffffffff906e5fc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8f49f8e0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_svc_export_set_reqs_doit+0x132/0x1470 fs/nfsd/export.c:1059
locks held by syz-executor/18783: 1, last CPU#0:
#0: ffffffff8f15c2a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8f15c2a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8f15c2a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#0: ffffffff8f15c2a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495
locks held by syz.5.2844/20208: 2, last CPU#1:
#0: ffffffff8f15c2a0 (rcu_read_lock){....}-{1:3}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:678
#1: ffff8880b85286d8 (hrtimer_bases.lock){-.-.}-{2:2}, at: lock_hrtimer_base kernel/time/hrtimer.c:192 [inline]
#1: ffff8880b85286d8 (hrtimer_bases.lock){-.-.}-{2:2}, at: hrtimer_start_range_ns_user+0x8c/0x430 kernel/time/hrtimer.c:1610
locks held by syz.5.2844/20211: 1, last CPU#0:
#0: ffff88807a1f9bc0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:586 [inline]
#0: ffff88807a1f9bc0 (&mm->mmap_lock){++++}-{4:4}, at: __mm_populate+0x182/0x390 mm/gup.c:1946
locks held by cmp/20218: 3, last CPU#0:
#0: ffff88807efdb440 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:548 [inline]
#0: ffff88807efdb440 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1dd/0x4e0 mm/util.c:579
#1: ffff888034de0628 (&mapping->i_mmap_rwsem){++++}-{4:4}, at: i_mmap_lock_write include/linux/fs.h:507 [inline]
#1: ffff888034de0628 (&mapping->i_mmap_rwsem){++++}-{4:4}, at: vma_prepare+0x12e/0x470 mm/vma.c:347
#2: ffffffff8f299990 (kfree_rcu_sheaf_map-wait-type-override){+.+.}-{3:3}, at: __kfree_rcu_sheaf+0x21/0x690 mm/slub.c:6242
locks held by modprobe/20219: 2, on CPU#0:
#0: ffff88807b150340 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:548 [inline]
#0: ffff88807b150340 (&mm->mmap_lock){++++}-{4:4}, at: do_mprotect_pkey+0x25c/0xd10 mm/mprotect.c:901
#1: ffff888034de0628 (&mapping->i_mmap_rwsem){++++}-{4:4}, at: i_mmap_lock_write include/linux/fs.h:507 [inline]
#1: ffff888034de0628 (&mapping->i_mmap_rwsem){++++}-{4:4}, at: vma_prepare+0x12e/0x470 mm/vma.c:347
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 33 Comm: khungtaskd Tainted: G L Y syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP, [Y]=FORCED_BIND
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:377 [inline]
watchdog+0x1058/0x10d0 kernel/hung_task.c:598
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
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: 20207 Comm: syz.5.2844 Tainted: G L Y syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP, [Y]=FORCED_BIND
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:rb_link_node include/linux/rbtree.h:98 [inline]
RIP: 0010:rb_add_augmented_cached include/linux/rbtree_augmented.h:82 [inline]
RIP: 0010:__enqueue_entity+0x331/0xc80 kernel/sched/fair.c:1085
Code: 89 ff e8 b2 a9 9e 00 4d 89 6e 20 49 83 c6 28 ba 10 00 00 00 4c 89 f7 31 f6 e8 7b ab 9e 00 48 89 d8 48 c1 e8 03 42 80 3c 20 00 <74> 08 48 89 df e8 85 a9 9e 00 4c 89 3b eb 0e 4d 8b 6d 00 49 83 e5
RSP: 0000:ffffc90004777be0 EFLAGS: 00000046
RAX: 1ffff11006144016 RBX: ffff888030a200b0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88804ab680b8
RBP: 0000000000000001 R08: ffff88804ab680b7 R09: 0000000000000000
R10: ffff88804ab680a8 R11: ffffed100956d017 R12: dffffc0000000000
R13: ffff888030a200a0 R14: ffff88804ab680a8 R15: ffff88804ab680a0
FS: 000055557aa5c500(0000) GS:ffff88812472e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000100 CR3: 0000000082e1c000 CR4: 00000000003526f0
Call Trace:
put_prev_set_next_task kernel/sched/sched.h:2817 [inline]
__pick_next_task+0x1c8/0x3c0 kernel/sched/core.c:6183
pick_next_task kernel/sched/core.c:6260 [inline]
__schedule+0xc77/0x5c60 kernel/sched/core.c:7220
__schedule_loop kernel/sched/core.c:7382 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7397
__exit_to_user_mode_loop kernel/entry/common.c:55 [inline]
exit_to_user_mode_loop kernel/entry/common.c:101 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:244 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:315 [inline]
irqentry_exit+0x291/0x910 kernel/entry/common.c:152
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0033:0x7f3350c517f0
Code: 74 28 48 85 c9 74 29 45 38 1c 10 75 23 83 c0 01 44 39 d0 75 dc 48 89 f0 25 ff 1f 00 00 49 89 34 c1 41 88 3c 00 31 c0 c3 66 90 <41> 38 3c 10 74 0b 41 88 3c 10 31 c0 49 89 34 d1 c3 b8 01 00 00 00
RSP: 002b:00007fffd9714dc8 EFLAGS: 00000246
RAX: 000000008246ff7f RBX: ffffffff8246ff7f RCX: ffffffff8246ff7f
RDX: 0000000000001f7f RSI: ffffffff8246ff7f RDI: 000000000000001b
RBP: 0000000000000000 R08: 00007f3351010000 R09: 00007f3351012000
R10: 000000008246ff83 R11: 000000000000001b R12: 00007f3351026128
R13: 000000000007ed8e R14: ffffffff8246ff7f R15: 00007f3351b55720