INFO: task syz.1.1117:17353 blocked for more than 143 seconds. Not tainted 6.11.0-rc7-syzkaller-00021-g7c6a3a65ace7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1117 state:D stack:24672 pid:17353 tgid:17352 ppid:16742 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 percpu_rwsem_wait+0x3c2/0x450 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xee/0x130 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:65 [inline] __sb_start_write include/linux/fs.h:1676 [inline] sb_start_write+0x184/0x1c0 include/linux/fs.h:1812 mnt_want_write+0x3f/0x90 fs/namespace.c:515 open_last_lookups fs/namei.c:3636 [inline] path_openat+0x779/0x3470 fs/namei.c:3883 do_filp_open+0x235/0x490 fs/namei.c:3913 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_openat fs/open.c:1447 [inline] __se_sys_openat fs/open.c:1442 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1442 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: 0033:0x7fbb37d7def9 RSP: 002b:00007fbb38ab6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fbb37f35f80 RCX: 00007fbb37d7def9 RDX: 000000000000275a RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007fbb37df0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fbb37f35f80 R15: 00007ffef5c18558 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 4 locks held by kworker/u8:7/2471: #0: ffff88801b6e3148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88801b6e3148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90008bf7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90008bf7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fa6d250 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:594 #3: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe9/0xa90 net/core/dev.c:11883 2 locks held by dhcpcd/4888: #0: ffff8880251e1678 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0x119/0x790 net/netlink/af_netlink.c:2404 #1: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_dumpit+0x99/0x200 net/core/rtnetlink.c:6506 2 locks held by getty/4981: #0: ffff88803035b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/u8:14/12442: #0: ffff88801a889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88801a889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90008c07d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90008c07d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 2 locks held by kworker/u8:17/12445: #0: ffff8880b893e998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:560 #1: ffff8880b8928948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:989 1 lock held by syz.1.1117/17353: #0: ffff88805fc7e420 (sb_writers#20){++++}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 1 lock held by syz-executor/18037: #0: ffffffff8e73d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline] #0: ffffffff8e73d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:958 1 lock held by syz-executor/18241: #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x1b0 drivers/net/tun.c:3510 1 lock held by syz-executor/18727: #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz-executor/18817: #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz.4.1260/18849: #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x48f/0x2400 drivers/net/tun.c:3120 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc7-syzkaller-00021-g7c6a3a65ace7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 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: 8019 Comm: syz.1.280 Not tainted 6.11.0-rc7-syzkaller-00021-g7c6a3a65ace7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:check_preemption_disabled+0x60/0x120 lib/smp_processor_id.c:19 Code: 00 48 3b 44 24 08 0f 85 ce 00 00 00 89 d8 48 83 c4 10 5b 41 5c 41 5e 41 5f c3 cc cc cc cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 04 24 00 02 00 00 74 c5 49 89 f6 49 89 ff 65 4c 8b 24 25 c0 d6 RSP: 0018:ffffc9000482fac0 EFLAGS: 00000046 RAX: 0000000080000000 RBX: 0000000000000000 RCX: ffff88802ce0da00 RDX: 0000000000000000 RSI: ffffffff8beae240 RDI: ffffffff8c3fbb00 RBP: ffffc9000482fc50 R08: ffff8880682262d7 R09: 1ffff1100d044c5a R10: dffffc0000000000 R11: ffffed100d044c5b R12: 0000000000000246 R13: ffff88802ce0da00 R14: 00000000ffffffff R15: ffffffff8e738380 FS: 00007f748ec576c0(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562bec615058 CR3: 0000000061f9e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:461 [inline] lock_is_held_type+0x7b/0x190 kernel/locking/lockdep.c:5830 lock_is_held include/linux/lockdep.h:249 [inline] __might_resched+0xa5/0x780 kernel/sched/core.c:8425 io_cqring_wait io_uring/io_uring.c:2497 [inline] __do_sys_io_uring_enter io_uring/io_uring.c:3255 [inline] __se_sys_io_uring_enter+0x1b8d/0x2670 io_uring/io_uring.c:3147 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: 0033:0x7f748dd7def9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f748ec57038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007f748df35f80 RCX: 00007f748dd7def9 RDX: 0000000000400000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f748ddf0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f748df35f80 R15: 00007ffe5a0fc748