INFO: task syz.5.2242:12166 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.2242 state:D stack:27984 pid:12166 ppid:4966 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
wb_wait_for_completion+0x16f/0x290 fs/fs-writeback.c:191
sync_inodes_sb+0x1c5/0xa10 fs/fs-writeback.c:2756
sync_filesystem+0x16d/0x220 fs/sync.c:64
generic_shutdown_super+0x6b/0x340 fs/super.c:474
kill_block_super+0x7c/0xe0 fs/super.c:1470
deactivate_locked_super+0x93/0xf0 fs/super.c:332
cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191
task_work_run+0x1d0/0x260 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc95639c629
RSP: 002b:00007fc957223028 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007fc956616090 RCX: 00007fc95639c629
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000000000003
RBP: 00007fc956432b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc956616128 R14: 00007fc956616090 R15: 00007fff03481068
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2dfb0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2e7d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
2 locks held by getty/4028:
#0: ffff88802f793098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x429/0x1390 drivers/tty/n_tty.c:2198
3 locks held by kworker/u4:8/4672:
#0: ffff888017616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#1: ffffc90005457d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#2: ffffffff8cb331c0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x600 kernel/rcu/tree.c:4023
2 locks held by kworker/u4:18/4692:
#0: ffff888018ad3938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#1: ffffc900055cfd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
1 lock held by segctord/8965:
2 locks held by syz.5.2242/12166:
#0: ffff888055b620e0 (&type->s_umount_key#93){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
#1: ffff8880246b47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
#1: ffff8880246b47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x1a9/0xa10 fs/fs-writeback.c:2754
1 lock held by syz.1.2410/12807:
#0: ffff888055b620e0 (&type->s_umount_key#93){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:755
1 lock held by syz.7.2811/14260:
#0: ffff888055b620e0 (&type->s_umount_key#93){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:755
1 lock held by syz.7.2811/14261:
#0: ffff888055b620e0 (&type->s_umount_key#93){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:755
1 lock held by syz-executor/15238:
#0: ffffffff8dd46428 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8dd46428 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6147
4 locks held by sed/15269:
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xeee/0xf30 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 15270 Comm: dhcpcd-run-hook Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:x2apic_send_IPI_self+0x0/0x70 arch/x86/kernel/apic/x2apic_phys.c:154
Code: 83 fe 20 73 07 89 d9 d3 f8 5b 5d c3 89 c6 89 da 48 c7 c7 20 91 99 8c 89 c5 e8 9c aa 00 03 89 e8 eb e3 0f 1f 84 00 00 00 00 00 <41> 57 41 56 53 89 fb 49 bf 00 00 00 00 00 fc ff df 48 c7 c0 60 fd
RSP: 0018:ffffc90003337090 EFLAGS: 00000246
RAX: 1ffffffff18c9f71 RBX: ffffffff8c64fb88 RCX: ffff888027d75940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00000000000000f6
RBP: 0000000000000000 R08: ffffc90003337007 R09: 1ffff92000666e00
R10: dffffc0000000000 R11: fffff52000666e01 R12: 0000000000000001
R13: 0000000000000001 R14: dffffc0000000000 R15: 0000000000000020
FS: 00007fd996d2cc80(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd996f907e8 CR3: 000000007e26e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31
irq_work_queue+0x95/0x140 kernel/irq_work.c:114
__kfence_alloc+0x29c/0x3d0 mm/kfence/core.c:1041
kfence_alloc include/linux/kfence.h:128 [inline]
slab_alloc_node mm/slub.c:3283 [inline]
slab_alloc mm/slub.c:3367 [inline]
__kmem_cache_alloc_lru mm/slub.c:3374 [inline]
kmem_cache_alloc+0x287/0x2f0 mm/slub.c:3383
ptlock_alloc mm/memory.c:6045 [inline]
ptlock_init include/linux/mm.h:2480 [inline]
pmd_ptlock_init include/linux/mm.h:2566 [inline]
pgtable_pmd_page_ctor include/linux/mm.h:2602 [inline]
pmd_alloc_one include/asm-generic/pgalloc.h:129 [inline]
__pmd_alloc+0x116/0x760 mm/memory.c:5487
pmd_alloc include/linux/mm.h:2430 [inline]
copy_pmd_range mm/memory.c:1157 [inline]
copy_pud_range mm/memory.c:1214 [inline]
copy_p4d_range mm/memory.c:1238 [inline]
copy_page_range+0x3471/0x3900 mm/memory.c:1332
dup_mmap kernel/fork.c:702 [inline]
dup_mm kernel/fork.c:1546 [inline]
copy_mm+0xec3/0x1690 kernel/fork.c:1595
copy_process+0x1979/0x4030 kernel/fork.c:2356
kernel_clone+0x24b/0x900 kernel/fork.c:2762
__do_sys_clone kernel/fork.c:2903 [inline]
__se_sys_clone kernel/fork.c:2887 [inline]
__x64_sys_clone+0x1a7/0x220 kernel/fork.c:2887
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd996ec6636
Code: 89 df e8 6d e8 f6 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 52 89 c5 85 c0 75 31 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffca39c6a60 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffca39c6a68 RCX: 00007fd996ec6636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 000055b410d56e60 R08: 0000000000000000 R09: 0000000000000000
R10: 00007fd996d2cf50 R11: 0000000000000246 R12: 000055b410d58f70
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000