INFO: task syz-executor.1:18741 blocked for more than 143 seconds. Not tainted 6.8.0-rc1-syzkaller-00037-g443b349019f2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:26480 pid:18741 tgid:18738 ppid:5091 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x177f/0x4960 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6874 rwsem_down_write_slowpath+0xeea/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common+0x1aa/0x200 kernel/locking/rwsem.c:1306 __super_lock fs/super.c:56 [inline] super_lock+0x196/0x400 fs/super.c:120 super_lock_excl fs/super.c:145 [inline] grab_super+0xaf/0x370 fs/super.c:534 sget_fc+0x1fa/0x770 fs/super.c:793 vfs_get_super fs/super.c:1268 [inline] get_tree_single+0x2f/0x140 fs/super.c:1300 vfs_get_tree+0x8c/0x2a0 fs/super.c:1784 do_new_mount+0x2be/0xb40 fs/namespace.c:3352 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f8db3c7cda9 RSP: 002b:00007f8db497c0c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f8db3dabf80 RCX: 00007f8db3c7cda9 RDX: 0000000020000140 RSI: 0000000020000100 RDI: 0000000000000000 RBP: 00007f8db3cc947a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f8db3dabf80 R15: 00007ffe858b2628 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d92ef20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8d92ef20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8d92ef20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 3 locks held by kworker/u4:7/2766: 2 locks held by udevd/4504: 2 locks held by getty/4810: #0: ffff888029bbb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 4 locks held by syz-executor.5/5097: 3 locks held by kworker/0:7/5164: #0: ffff88802963e138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff88802963e138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc900046f7d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc900046f7d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8eb48a48 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4129 2 locks held by kworker/1:3/17934: #0: ffff88801308a938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff88801308a938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc90014a37d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc90014a37d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 2 locks held by syz-executor.3/18542: 1 lock held by syz-executor.1/18741: #0: ffff88801e2ea0e0 (&type->s_umount_key#130){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88801e2ea0e0 (&type->s_umount_key#130){+.+.}-{3:3}, at: super_lock+0x196/0x400 fs/super.c:120 1 lock held by syz-executor.1/19207: #0: ffff88801e2ea0e0 (&type->s_umount_key#130){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88801e2ea0e0 (&type->s_umount_key#130){+.+.}-{3:3}, at: super_lock+0x196/0x400 fs/super.c:120 1 lock held by syz-executor.1/19614: #0: ffff88801e2ea0e0 (&type->s_umount_key#130){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88801e2ea0e0 (&type->s_umount_key#130){+.+.}-{3:3}, at: super_lock+0x196/0x400 fs/super.c:120 4 locks held by syz-executor.0/19703: #0: ffff8880b993c918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 #1: ffff8880b9928988 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:988 #2: ffffffff8d614748 (mount_lock.seqcount){+.+.}-{0:0}, at: ksys_umount fs/namespace.c:1919 [inline] #2: ffffffff8d614748 (mount_lock.seqcount){+.+.}-{0:0}, at: __do_sys_umount fs/namespace.c:1924 [inline] #2: ffffffff8d614748 (mount_lock.seqcount){+.+.}-{0:0}, at: __se_sys_umount fs/namespace.c:1922 [inline] #2: ffffffff8d614748 (mount_lock.seqcount){+.+.}-{0:0}, at: __x64_sys_umount+0x126/0x170 fs/namespace.c:1922 #3: ffffffff8e01bf48 (pool_rwlock){----}-{2:2}, at: stack_depot_save_flags+0x150/0x650 lib/stackdepot.c:508 2 locks held by syz-executor.1/19909: #0: ffffffff8eb48a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8eb48a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1030 net/core/rtnetlink.c:6612 #1: ffffffff8d9348b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #1: ffffffff8d9348b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x46c/0x890 kernel/rcu/tree_exp.h:996 1 lock held by syz-executor.5/20196: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc1-syzkaller-00037-g443b349019f2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x498/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x310 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfaf/0xff0 kernel/hung_task.c:379 kthread+0x2d3/0x370 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 18542 Comm: syz-executor.3 Not tainted 6.8.0-rc1-syzkaller-00037-g443b349019f2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 RIP: 0010:check_preemption_disabled+0x42/0x110 lib/smp_processor_id.c:55 Code: 08 65 8b 1d 3c 25 dd 74 65 8b 05 31 25 dd 74 a9 ff ff ff 7f 74 22 65 48 8b 04 25 28 00 00 00 48 3b 44 24 08 0f 85 c9 00 00 00 <89> d8 48 83 c4 10 5b 41 5c 41 5e 41 5f c3 48 c7 04 24 00 00 00 00 RSP: 0018:ffffc90004bf7ae0 EFLAGS: 00000246 RAX: 30d0d964894f1c00 RBX: 0000000000000000 RCX: ffff888029d55940 RDX: ffff888029d55940 RSI: ffffffff8bbe9240 RDI: ffffffff8bbe9200 RBP: 0000000000000001 R08: ffffffff8202d6b4 R09: 1ffffffff21bee7c R10: dffffc0000000000 R11: fffffbfff21bee7d R12: ffffc90004bf7c00 R13: 0000000000000000 R14: ffff88806da930d8 R15: dffffc0000000000 FS: 000055555702a480(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8c823ad988 CR3: 000000002b9ad000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:700 rcu_read_lock include/linux/rcupdate.h:751 [inline] d_walk+0x2f2/0x700 fs/dcache.c:1282 shrink_dcache_parent+0x144/0x3b0 fs/dcache.c:1487 do_one_tree+0x23/0xe0 fs/dcache.c:1538 shrink_dcache_for_umount+0x7d/0x130 fs/dcache.c:1555 generic_shutdown_super+0x6a/0x2c0 fs/super.c:624 kill_anon_super fs/super.c:1230 [inline] kill_litter_super+0x76/0xb0 fs/super.c:1240 gadgetfs_kill_sb+0x26/0x110 drivers/usb/gadget/legacy/inode.c:2111 deactivate_locked_super+0xc1/0x130 fs/super.c:477 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1267 task_work_run+0x24a/0x300 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:108 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0x167/0x370 kernel/entry/common.c:212 do_syscall_64+0x102/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f9a3767bc9a Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24 RSP: 002b:00007ffdc9d11f30 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 00007f9a3767bc9a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007f9a377ad980 R08: 0000001b31420000 R09: 000000000000006e R10: 0000000081c0ec3d R11: 0000000000000293 R12: 00000000000d0169 R13: ffffffffffffffff R14: 00007f9a37200000 R15: 00000000000cfe28