INFO: task syz.2.3196:18740 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.3196 state:D stack:26840 pid:18740 tgid:18738 ppid:16049 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x1b2a/0x59a0 kernel/sched/core.c:7232
__schedule_loop kernel/sched/core.c:7309 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7324
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7381
rwsem_down_read_slowpath+0x6ba/0x920 kernel/locking/rwsem.c:1114
__down_read_common kernel/locking/rwsem.c:1291 [inline]
__down_read kernel/locking/rwsem.c:1304 [inline]
down_read+0x9c/0x330 kernel/locking/rwsem.c:1576
__super_lock fs/super.c:62 [inline]
super_lock+0x2d6/0x3d0 fs/super.c:124
__iterate_supers+0x26b/0x420 fs/super.c:994
quota_sync_all fs/quota/quota.c:69 [inline]
__do_sys_quotactl fs/quota/quota.c:938 [inline]
__se_sys_quotactl+0x3a0/0x9a0 fs/quota/quota.c:917
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x510 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff76219e0d9
RSP: 002b:00007ff763047028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007ff762426090 RCX: 00007ff76219e0d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000102
RBP: 00007ff762235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff762426128 R14: 00007ff762426090 R15: 00007ffe3baf94f8
Showing all locks held in the system:
locks held by kworker/0:0H/11: 2, last CPU#0:
#0: ffff88801b02ed40 ((wq_completion)events_highpri){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88801b02ed40 ((wq_completion)events_highpri){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88801b02ed40 ((wq_completion)events_highpri){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#0: ffff88801b02ed40 ((wq_completion)events_highpri){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
#1: ffffc90000107c40 ((work_completion)(&vmidi->output_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90000107c40 ((work_completion)(&vmidi->output_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90000107c40 ((work_completion)(&vmidi->output_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#1: ffffc90000107c40 ((work_completion)(&vmidi->output_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
locks held by khungtaskd/32: 1, last CPU#0:
#0: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6837
locks held by kworker/0:2/192: 2, last CPU#0:
#0: ffff88801b02dd40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88801b02dd40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88801b02dd40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#0: ffff88801b02dd40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
#1: ffffc9000304fc40 ((gc_work).work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc9000304fc40 ((gc_work).work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc9000304fc40 ((gc_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#1: ffffc9000304fc40 ((gc_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
locks held by udevd/4984: 2, last CPU#0:
#0: ffff888023db9f70 (&u->iolock){+.+.}-{4:4}, at: __unix_dgram_recvmsg+0x1e3/0xd70 net/unix/af_unix.c:2575
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495
locks held by getty/5371: 2, on CPU#1:
#0: ffff88803395c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by syz-executor/5902: 2, last CPU#0:
#0: ffff888025cde0e8 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888025cde0e8 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock_excl fs/super.c:75 [inline]
#0: ffff888025cde0e8 (&type->s_umount_key#96){++++}-{4:4}, at: deactivate_super+0xac/0xe0 fs/super.c:631
#1: ffff888035dd4328 (&sbi->cp_global_sem_key){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2455 [inline]
#1: ffff888035dd4328 (&sbi->cp_global_sem_key){+.+.}-{4:4}, at: f2fs_down_write_trace+0x34/0x1f0 fs/f2fs/checkpoint.c:180
locks held by syz.2.3196/18740: 1, on CPU#0:
#0: ffff888025cde0e8 (&type->s_umount_key#96){++++}-{4:4}, at: __super_lock fs/super.c:62 [inline]
#0: ffff888025cde0e8 (&type->s_umount_key#96){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:124
locks held by syz-executor/19009: 1, last CPU#0:
#0: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#0: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495
locks held by syz.6.3617/20502: 2, last CPU#0:
#0: ffff88807e7603b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline]
#0: ffff88807e7603b8 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x1a4/0x9f0 mm/mmap.c:1299
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290
locks held by dhcpcd-run-hook/20506: 2, last CPU#0:
#0: ffff8880591241c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495
locks held by syz.1.3624/20525: 1, last CPU#0:
#0: ffffffff8eb5c898 (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline]
#0: ffffffff8eb5c898 (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: rcu_read_lock_trace include/linux/rcupdate_trace.h:101 [inline]
#0: ffffffff8eb5c898 (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: class_rcu_tasks_trace_constructor include/linux/rcupdate_trace.h:226 [inline]
#0: ffffffff8eb5c898 (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: __do_trace_sys_enter include/trace/events/syscalls.h:18 [inline]
#0: ffffffff8eb5c898 (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: trace_sys_enter include/trace/events/syscalls.h:18 [inline]
#0: ffffffff8eb5c898 (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: trace_syscall_enter+0x58/0x110 kernel/entry/syscall-common.c:13
locks held by syz.8.3625/20534: 1, last CPU#0:
#0: ffff88807db66370 (&u->iolock){+.+.}-{4:4}, at: __unix_dgram_recvmsg+0x1e3/0xd70 net/unix/af_unix.c:2575
locks held by dhcpcd-run-hook/20533: 4, last CPU#0:
#0: ffff8880340c31c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: do_fault_around mm/memory.c:5953 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: do_read_fault mm/memory.c:5987 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: do_fault mm/memory.c:6130 [inline]
#1: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: do_pte_missing+0x140c/0x34b0 mm/memory.c:4696
#2: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#2: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#2: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: filemap_map_pages+0x1d1/0x2170 mm/filemap.c:3921
#3: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#3: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#3: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
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:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 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