INFO: task syz.1.1022:11538 blocked for more than 145 seconds. Not tainted 6.11.0-next-20240926-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1022 state:D stack:25168 pid:11538 tgid:11537 ppid:8258 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:625 nfsd_umount+0x43/0xd0 fs/nfsd/nfsctl.c:1428 deactivate_locked_super+0xc4/0x130 fs/super.c:473 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373 task_work_run+0x24f/0x310 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f697ed7df39 RSP: 002b:00007f697fab0038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffec RBX: 00007f697ef35f80 RCX: 00007f697ed7df39 RDX: 0000000020000580 RSI: 00000000200005c0 RDI: 0000000000000000 RBP: 00007f697edf0216 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f697ef35f80 R15: 00007ffcbe09c0d8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937f20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937f20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937f20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 3 locks held by kworker/1:1/51: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000bb7d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000bb7d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffff888044304240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x2d1/0x4130 drivers/net/netdevsim/fib.c:1489 2 locks held by getty/4988: #0: ffff8880320b20a0 (&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+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:4/5290: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90004067d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90004067d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffff888069566240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x2d1/0x4130 drivers/net/netdevsim/fib.c:1489 2 locks held by syz.2.927/10982: #0: ffffffff8fd3aef0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8ec1c2e8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nl_listener_set_doit+0x12d/0x1a90 fs/nfsd/nfsctl.c:1964 2 locks held by syz.1.1022/11538: #0: ffff88802afc20e0 (&type->s_umount_key#121){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88802afc20e0 (&type->s_umount_key#121){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88802afc20e0 (&type->s_umount_key#121){++++}-{3:3}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8ec1c2e8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:625 1 lock held by syz-executor/11923: #0: ffffffff8e93d4b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93d4b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 1 lock held by syz-executor/12499: #0: ffffffff8e93d4b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93d4b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 1 lock held by syz.1.1142/12520: #0: ffff88802afc20e0 (&type->s_umount_key#121){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88802afc20e0 (&type->s_umount_key#121){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-next-20240926-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 4667 Comm: syslogd Not tainted 6.11.0-next-20240926-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:kasan_mem_to_shadow include/linux/kasan.h:61 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:130 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x4f/0x290 mm/kasan/generic.c:189 Code: 89 fd 48 c1 ed 2f 81 fd fe ff 01 00 0f 86 43 02 00 00 48 89 fb 48 c1 eb 03 49 ba 00 00 00 00 00 fc ff df 4e 8d 1c 13 49 ff c8 <4d> 89 c1 49 c1 e9 03 49 be 01 00 00 00 00 fc ff df 4f 8d 3c 31 4c RSP: 0018:ffffc9000310f550 EFLAGS: 00000296 RAX: 0000000000000001 RBX: 1ffffffff203a495 RCX: ffffffff81703f04 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff901d24a8 RBP: 000000000001ffff R08: ffffffff901d24af R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff203a495 R12: 1ffff92000621eb8 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff1100f876469 FS: 00007fd60c56a380(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a554fc46d8 CR3: 000000007c778000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:570 [inline] cpu_online include/linux/cpumask.h:1117 [inline] trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0xd4/0x550 kernel/locking/lockdep.c:5796 __might_fault+0xc6/0x120 mm/memory.c:6722 _copy_to_iter+0x108/0x1d60 lib/iov_iter.c:184 copy_to_iter include/linux/uio.h:211 [inline] simple_copy_to_iter net/core/datagram.c:524 [inline] __skb_datagram_iter+0x107/0x900 net/core/datagram.c:401 skb_copy_datagram_iter+0xd1/0x250 net/core/datagram.c:538 skb_copy_datagram_msg include/linux/skbuff.h:4076 [inline] __unix_dgram_recvmsg+0x7e3/0x12f0 net/unix/af_unix.c:2479 sock_recvmsg_nosec net/socket.c:1052 [inline] sock_recvmsg+0x22f/0x280 net/socket.c:1074 sock_read_iter+0x2c4/0x3d0 net/socket.c:1144 new_sync_read fs/read_write.c:488 [inline] vfs_read+0x9bb/0xbc0 fs/read_write.c:569 ksys_read+0x183/0x2b0 fs/read_write.c:712 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd60c6beb6a Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffeba18dfb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fd60c6beb6a RDX: 00000000000000ff RSI: 000055e035def950 RDI: 0000000000000000 RBP: 000055e035def910 R08: 0000000000000001 R09: 0000000000000000 R10: 00007fd60c85d3a3 R11: 0000000000000246 R12: 000055e035def99f R13: 000055e035def950 R14: 0000000000000000 R15: 00007fd60c8a1a80