INFO: task syz.0.686:7088 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.686 state:D stack:25296 pid:7088 ppid:4276 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2144 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x2c2/0x590 kernel/sched/completion.c:138 kthread_stop+0x197/0x650 kernel/kthread.c:711 signal_our_withdraw fs/gfs2/util.c:159 [inline] gfs2_withdraw+0x56f/0x1450 fs/gfs2/util.c:345 gfs2_meta_check_ii+0x6e/0x80 fs/gfs2/util.c:502 gfs2_metatype_check_i fs/gfs2/util.h:126 [inline] gfs2_quota_init+0xc53/0xe80 fs/gfs2/quota.c:1406 gfs2_make_fs_rw+0x41c/0x590 fs/gfs2/super.c:159 gfs2_fill_super+0x192c/0x2020 fs/gfs2/ops_fstype.c:1271 get_tree_bdev+0x3e6/0x610 fs/super.c:1366 gfs2_get_tree+0x4d/0x1e0 fs/gfs2/ops_fstype.c:1327 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x247/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606 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: 0033:0x7f57c339e0ca RSP: 002b:00007f57c42b5e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f57c42b5ee0 RCX: 00007f57c339e0ca RDX: 00002000000124c0 RSI: 0000200000012500 RDI: 00007f57c42b5ea0 RBP: 00002000000124c0 R08: 00007f57c42b5ee0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000012500 R13: 00007f57c42b5ea0 R14: 00000000000125f6 R15: 0000200000000180 INFO: task gfs2_quotad:7092 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:gfs2_quotad state:D stack:27888 pid:7092 ppid:2 flags:0x00024000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 bit_wait+0xd/0xc0 kernel/sched/wait_bit.c:199 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64 wait_on_bit include/linux/wait_bit.h:76 [inline] __gfs2_glock_dq+0x6b1/0xa20 fs/gfs2/glock.c:1646 gfs2_glock_dq+0x1a8/0x1c0 fs/gfs2/glock.c:1718 gfs2_glock_dq_uninit+0x24/0xe0 fs/gfs2/glock.c:1738 gfs2_statfs_sync+0x738/0x7e0 fs/gfs2/super.c:314 quotad_check_timeo fs/gfs2/quota.c:1519 [inline] gfs2_quotad+0x38a/0x690 fs/gfs2/quota.c:1561 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2e4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/27: #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by kworker/1:1/41: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 #1: ffffc90000b27d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 2 locks held by getty/4029: #0: ffff88814ccae098 (&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+0x41e/0x1360 drivers/tty/n_tty.c:2198 2 locks held by kworker/u4:13/4479: 3 locks held by kworker/u4:17/4746: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 #1: ffffc9000c37fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 #2: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263 2 locks held by syz.0.686/7088: #0: ffff888075ffe0e0 (&type->s_umount_key#80/1){+.+.}-{3:3}, at: alloc_super+0x1fb/0x930 fs/super.c:228 #1: ffff888018aad248 (&sdp->sd_freeze_mutex){+.+.}-{3:3}, at: signal_our_withdraw fs/gfs2/util.c:155 [inline] #1: ffff888018aad248 (&sdp->sd_freeze_mutex){+.+.}-{3:3}, at: gfs2_withdraw+0x506/0x1450 fs/gfs2/util.c:345 2 locks held by syz.1.1126/8615: #0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3495 #1: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962 1 lock held by syz.4.1129/8632: #0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3495 1 lock held by syz.4.1129/8634: #0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3495 1 lock held by syz.4.1129/8636: #0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x54d/0xe80 net/core/dev_ioctl.c:571 1 lock held by syz.2.1130/8639: #0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x80d/0xfb0 net/core/rtnetlink.c:6155 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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+0xf0e/0xf50 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 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 1 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:741