INFO: task kworker/u8:9:6019 blocked for more than 143 seconds. Not tainted 6.9.0-rc4-syzkaller-00266-g977b1ef51866 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:9 state:D stack:20312 pid:6019 tgid:6019 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:3) Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x1796/0x4a00 kernel/sched/core.c:6746 __schedule_loop kernel/sched/core.c:6823 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6838 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6895 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common+0x1af/0x200 kernel/locking/rwsem.c:1306 f2fs_down_write fs/f2fs/f2fs.h:2173 [inline] f2fs_issue_checkpoint+0x2d6/0x4e0 fs/f2fs/checkpoint.c:1870 f2fs_balance_fs_bg+0x534/0x970 fs/f2fs/segment.c:520 f2fs_write_node_pages+0x147/0x6d0 fs/f2fs/node.c:2126 do_writepages+0x359/0x870 mm/page-writeback.c:2612 __writeback_single_inode+0x165/0x10b0 fs/fs-writeback.c:1650 writeback_sb_inodes+0x905/0x1260 fs/fs-writeback.c:1941 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2012 wb_writeback+0x46b/0xce0 fs/fs-writeback.c:2119 wb_check_background_flush fs/fs-writeback.c:2189 [inline] wb_do_writeback fs/fs-writeback.c:2277 [inline] wb_workfn+0xc58/0x1090 fs/fs-writeback.c:2304 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: 4 locks held by kworker/u8:0/10: #0: ffff888015ecb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline] #0: ffff888015ecb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3335 #1: ffffc900000f7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline] #1: ffffc900000f7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x17c0 kernel/workqueue.c:3335 #2: ffffffff8f586910 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:591 #3: ffffffff8f593008 (rtnl_mutex){+.+.}-{3:3}, at: mpls_net_exit+0x7d/0x2a0 net/mpls/af_mpls.c:2725 1 lock held by khungtaskd/29: #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 4 locks held by kworker/u8:4/60: #0: ffff8880b953e658 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 #1: ffff8880b9528948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:988 #2: ffff888056a48768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:5953 [inline] #2: ffff888056a48768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: cfg80211_wiphy_work+0x35/0x260 net/wireless/core.c:424 #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: ieee80211_sta_active_ibss+0xc7/0x330 net/mac80211/ibss.c:642 3 locks held by kworker/u8:7/2473: 3 locks held by kworker/1:2/3000: #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline] #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3335 #1: ffffc9000af27d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline] #1: ffffc9000af27d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x17c0 kernel/workqueue.c:3335 #2: ffffffff8f593008 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 1 lock held by dhcpcd/4739: #0: ffffffff8f593008 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1bc0 net/ipv4/devinet.c:1096 2 locks held by getty/4824: #0: ffff88802a77c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f0e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201 4 locks held by kworker/u8:9/6019: #0: ffff88801aed6948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline] #0: ffff88801aed6948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3335 #1: ffffc90003067d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline] #1: ffffc90003067d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x17c0 kernel/workqueue.c:3335 #2: ffff88807ab0c0e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:561 #3: ffff888056a6d2a0 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2173 [inline] #3: ffff888056a6d2a0 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_issue_checkpoint+0x2d6/0x4e0 fs/f2fs/checkpoint.c:1870 5 locks held by syz-executor.3/12250: 1 lock held by syz-executor.3/13681: #0: ffff88807ab0c0e0 (&type->s_umount_key#56){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807ab0c0e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_lock+0x196/0x400 fs/super.c:120 2 locks held by syz-executor.2/14406: #0: ffffffff8f593008 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f593008 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x10d0 net/core/rtnetlink.c:6592 #1: ffffffff8e33a0b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #1: ffffffff8e33a0b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x463/0x820 kernel/rcu/tree_exp.h:939 2 locks held by syz-executor.3/14462: 2 locks held by syz-executor.0/14500: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.9.0-rc4-syzkaller-00266-g977b1ef51866 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xfde/0x1020 kernel/hung_task.c:380 kthread+0x2f0/0x390 kernel/kthread.c:388 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4525 Comm: udevd Not tainted 6.9.0-rc4-syzkaller-00266-g977b1ef51866 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:validate_chain+0xa/0x58e0 kernel/locking/lockdep.c:3825 Code: 00 48 89 d9 e9 54 ff ff ff e8 f2 d0 03 0a 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 48 83 e4 e0 48 81 ec c0 02 00 00 49 89 ce 89 RSP: 0018:ffffc90003687598 EFLAGS: 00000086 RAX: 1ffffffff257c5c1 RBX: ffffffff92be2e08 RCX: 58cce5e7c8d5ebdc RDX: 0000000000000001 RSI: ffff88806ad446d8 RDI: ffff88806ad43c00 RBP: ffffc900036875a0 R08: ffffffff92efb507 R09: 1ffffffff25df6a0 R10: dffffc0000000000 R11: fffffbfff25df6a1 R12: ffff88806ad43c00 R13: ffff88806ad43c00 R14: 0000000000000001 R15: ffff88806ad43c00 FS: 00007f7822aa3c80(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055b5f92c3000 CR3: 000000006a5d6000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 rcu_lock_acquire include/linux/rcupdate.h:329 [inline] rcu_read_lock include/linux/rcupdate.h:781 [inline] net_generic+0x3c/0x240 include/net/netns/generic.h:45 netlink_deliver_tap+0x1f/0x1b0 net/netlink/af_netlink.c:333 __netlink_sendskb net/netlink/af_netlink.c:1279 [inline] netlink_sendskb+0x68/0x140 net/netlink/af_netlink.c:1288 netlink_unicast+0x39d/0x980 net/netlink/af_netlink.c:1376 netlink_sendmsg+0x8e1/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7822724a4b Code: ff 89 ef 48 89 04 24 e8 22 56 f9 ff 48 8b 04 24 48 83 c4 20 5d c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6d 48 8b 15 ae c3 0c 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffc83d571f8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000055b5f9230df0 RCX: 00007f7822724a4b RDX: 0000000000000000 RSI: 00007ffc83d57208 RDI: 0000000000000004 RBP: 000055b5f9241f10 R08: 0000000000000001 R09: 3b50c5c200dc0c70 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000072 R14: 0000000000000000 R15: 0000000000000000