INFO: task syz-executor:4967 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21824 pid: 4967 ppid: 1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165
deactivate_super+0xa0/0xd0 fs/super.c:365
cleanup_mnt+0x418/0x4d0 fs/namespace.c:1139
task_work_run+0x125/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd1583d7117
RSP: 002b:00007ffe3367b498 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fd15845708c RCX: 00007fd1583d7117
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3367b550
RBP: 00007ffe3367b550 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe3367c5e0
R13: 00007fd15845708c R14: 000000000001d462 R15: 00007ffe3367c620
INFO: task syz.1.17:5319 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.17 state:D stack:26848 pid: 5319 ppid: 4960 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
rwsem_down_read_slowpath+0x528/0x990 kernel/locking/rwsem.c:1055
__down_read_common kernel/locking/rwsem.c:1239 [inline]
__down_read kernel/locking/rwsem.c:1252 [inline]
down_read+0x96/0x2e0 kernel/locking/rwsem.c:1500
iterate_supers+0xa4/0x1d0 fs/super.c:716
quota_sync_all fs/quota/quota.c:68 [inline]
__do_sys_quotactl fs/quota/quota.c:936 [inline]
__se_sys_quotactl+0x33a/0x6c0 fs/quota/quota.c:915
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f33267a1de9
RSP: 002b:00007f3325a13038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f33269bafa0 RCX: 00007f33267a1de9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 00007f33268232a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f33269bafa0 R15: 00007ffcca9d4a18
INFO: task syz.2.18:5326 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.18 state:D stack:26848 pid: 5326 ppid: 4964 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
rwsem_down_read_slowpath+0x528/0x990 kernel/locking/rwsem.c:1055
__down_read_common kernel/locking/rwsem.c:1239 [inline]
__down_read kernel/locking/rwsem.c:1252 [inline]
down_read+0x96/0x2e0 kernel/locking/rwsem.c:1500
iterate_supers+0xa4/0x1d0 fs/super.c:716
quota_sync_all fs/quota/quota.c:68 [inline]
__do_sys_quotactl fs/quota/quota.c:936 [inline]
__se_sys_quotactl+0x33a/0x6c0 fs/quota/quota.c:915
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ff42e993de9
RSP: 002b:00007ff42dc05038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007ff42ebacfa0 RCX: 00007ff42e993de9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 00007ff42ea152a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007ff42ebacfa0 R15: 00007ffe382bb5e8
INFO: task syz.4.20:5335 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.20 state:D stack:26848 pid: 5335 ppid: 4966 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
rwsem_down_read_slowpath+0x528/0x990 kernel/locking/rwsem.c:1055
__down_read_common kernel/locking/rwsem.c:1239 [inline]
__down_read kernel/locking/rwsem.c:1252 [inline]
down_read+0x96/0x2e0 kernel/locking/rwsem.c:1500
iterate_supers+0xa4/0x1d0 fs/super.c:716
quota_sync_all fs/quota/quota.c:68 [inline]
__do_sys_quotactl fs/quota/quota.c:936 [inline]
__se_sys_quotactl+0x33a/0x6c0 fs/quota/quota.c:915
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd408306de9
RSP: 002b:00007fd407578038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fd40851ffa0 RCX: 00007fd408306de9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 00007fd4083882a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fd40851ffa0 R15: 00007ffe77520278
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c11c660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/u4:1/144:
2 locks held by getty/3946:
#0: ffff88802b91d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
3 locks held by kworker/u4:5/4249:
#0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90002fbfd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d238308 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
3 locks held by kworker/1:6/4277:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc900030cfd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffff888029f5b240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x271/0x3240 drivers/net/netdevsim/fib.c:1480
3 locks held by kworker/1:12/4284:
#0: ffff88814c704938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000312fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffffffff8d238308 (rtnl_mutex
){+.+.}-{3:3}
, at: try_to_wake_up+0x5c/0x1050 kernel/sched/core.c:4049
1 lock held by syz-executor/4967:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
3 locks held by syz.0.16/5314:
1 lock held by syz.1.17/5319:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.2.18/5326:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.4.20/5335:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.9.26/5856:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.8.25/5860:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.6.23/5865:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.5.22/5869:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.7.24/5870:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.0.27/5925:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.1.28/5968:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.2.29/5989:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.3.30/5992:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.4.31/5995:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.9.32/6024:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.5.33/6054:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.6.34/6096:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.7.35/6139:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.8.36/6146:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.0.37/6167:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.1.38/6180:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.2.39/6201:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.3.40/6239:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.4.41/6258:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.9.42/6296:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.5.43/6318:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.6.44/6342:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.7.45/6369:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.8.46/6397:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.0.47/6425:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.1.48/6455:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz.2.49/6463:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
1 lock held by syz-executor/6472:
#0: ffffffff8d238308 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d238308 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x974/0xe60 net/core/rtnetlink.c:5647
1 lock held by syz.3.50/6485:
#0: ffff88807887e0e0 (&type->s_umount_key#72){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
2 locks held by syz-executor/6495:
#0: ffffffff8d238308 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d238308 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x974/0xe60 net/core/rtnetlink.c:5647
#1: ffffffff8c1210e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
#1: ffffffff8c1210e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 1235 Comm: kworker/u4:4 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: writeback wb_workfn (flush-8:0)
RIP: 0010:__lock_acquire+0x4c6/0x7c60 kernel/locking/lockdep.c:4955
Code: 68 83 e0 01 c1 e0 12 09 c8 8b 8c 24 c8 00 00 00 c1 e1 13 41 c1 e5 14 41 09 cd 45 09 f5 41 09 c5 48 8b 44 24 58 42 0f b6 04 00 <84> c0 0f 85 13 62 00 00 44 8b 75 28 45 89 6f 20 49 8d 5f 24 48 89
RSP: 0018:ffffc90004a964a0 EFLAGS: 00000006
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 000000000000002b RSI: 0000000000000000 RDI: ffff8880220ac748
RBP: ffffc90004a966f0 R08: dffffc0000000000 R09: 0000000000000000
R10: fffffbfff1ad32b6 R11: 1ffffffff1ad32b5 R12: ffff8880220ac654
R13: 000000000004002b R14: 000000000000002b R15: ffff8880220ac738
FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055f215b50a38 CR3: 000000005a129000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
page_vma_mapped_walk+0x1468/0x1740 mm/page_vma_mapped.c:-1
page_mkclean_one+0x148/0x380 mm/rmap.c:926
rmap_walk_file+0x408/0x610 mm/rmap.c:2378
rmap_walk mm/rmap.c:2396 [inline]
page_mkclean+0x2da/0x3e0 mm/rmap.c:1006
clear_page_dirty_for_io+0x402/0x9e0 mm/page-writeback.c:2749
mpage_submit_page+0x8a/0x210 fs/ext4/inode.c:2093
mpage_process_page_bufs+0x6d8/0x8b0 fs/ext4/inode.c:2227
mpage_prepare_extent_to_map+0xb7d/0xf70 fs/ext4/inode.c:2655
ext4_writepages+0xa09/0x2d20 fs/ext4/inode.c:2783
do_writepages+0x48d/0x6d0 mm/page-writeback.c:2386
__writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1647
writeback_sb_inodes+0x9fe/0x1610 fs/fs-writeback.c:1930
__writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2001
wb_writeback+0x455/0xb90 fs/fs-writeback.c:2106
wb_check_background_flush fs/fs-writeback.c:2172 [inline]
wb_do_writeback fs/fs-writeback.c:2260 [inline]
wb_workfn+0xb47/0xe60 fs/fs-writeback.c:2288
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287