INFO: task syz-executor.1:4844 blocked for more than 143 seconds. Not tainted 5.15.167-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:21944 pid: 4844 ppid: 3883 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 __writeback_inodes_sb_nr+0x2ce/0x370 fs/fs-writeback.c:2684 try_to_writeback_inodes_sb+0x94/0xb0 fs/fs-writeback.c:2732 ext4_nonda_switch fs/ext4/inode.c:2944 [inline] ext4_da_write_begin+0x228/0xb60 fs/ext4/inode.c:2971 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785 ext4_buffered_write_iter+0x227/0x360 fs/ext4/file.c:268 ext4_file_write_iter+0x87c/0x1990 __kernel_write+0x5b1/0xa60 fs/read_write.c:539 __dump_emit+0x264/0x3a0 fs/coredump.c:875 dump_user_range+0x91/0x320 fs/coredump.c:949 elf_core_dump+0x3c7d/0x4570 fs/binfmt_elf.c:2285 do_coredump+0x1852/0x31e0 fs/coredump.c:826 get_signal+0xc06/0x14e0 kernel/signal.c:2883 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320 exc_page_fault+0x342/0x700 arch/x86/mm/fault.c:1504 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568 RIP: 0033:0x0 RSP: 002b:0000000020000588 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f21f5c40050 RCX: 00007f21f5b11da9 RDX: 00000000200005c0 RSI: 0000000020000580 RDI: 0000000024080000 RBP: 00007f21f5b5e47a R08: 0000000020000640 R09: 0000000020000640 R10: 0000000020000600 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000006e R14: 00007f21f5c40050 R15: 00007fffa420fa98 Showing all locks held in the system: 6 locks held by kworker/u4:0/9: #0: ffff8880171d5938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90000ce7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8da261d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:561 #3: ffffffff8da31d88 (rtnl_mutex){+.+.}-{3:3}, at: wg_netns_pre_exit+0x1b/0x1d0 drivers/net/wireguard/device.c:404 #4: ffff88806677d3e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_netns_pre_exit+0xb6/0x1d0 drivers/net/wireguard/device.c:409 #5: ffffffff8c924228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #5: ffffffff8c924228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845 1 lock held by khungtaskd/27: #0: ffffffff8c91fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 3 locks held by kworker/u4:5/2654: #0: ffff888017079138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000b10fd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8da31d88 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 2 locks held by getty/3323: #0: ffff888029c53098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc9000208e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 2 locks held by kworker/1:6/4034: #0: ffff888017072138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003397d20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 3 locks held by kworker/u4:6/4214: 3 locks held by syz-executor.1/4844: #0: ffff888029e72460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff8880746921d8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline] #1: ffff8880746921d8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xa0/0x360 fs/ext4/file.c:262 #2: ffff888029e720e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x1d/0xb0 fs/fs-writeback.c:2729 1 lock held by syz-executor.3/7668: 1 lock held by syz-executor.3/7872: 1 lock held by syz-executor.1/7888: 1 lock held by syz-executor.3/8056: 1 lock held by syz-executor.1/8058: 1 lock held by syz-executor.1/8063: 1 lock held by syz-executor.4/8098: 1 lock held by syz-executor.3/8105: 1 lock held by syz-executor.1/8114: 1 lock held by syz-executor.0/8116: 1 lock held by syz-executor.0/8125: 1 lock held by syz-executor.3/8132: 1 lock held by syz-executor.4/8135: #0: ffff888029e74bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2688 1 lock held by syz-executor.4/8191: 1 lock held by syz-executor.3/8201: 1 lock held by syz-executor.1/8216: 3 locks held by syz-executor.0/8263: 1 lock held by syz-executor.1/8274: 1 lock held by syz-executor.3/8278: 1 lock held by syz-executor.3/8289: 1 lock held by syz-executor.4/8292: 1 lock held by syz-executor.1/9090: 1 lock held by syz-executor.3/9720: 1 lock held by syz-executor.4/9982: #0: ffff888029e74bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2688 1 lock held by syz-executor.3/10152: 3 locks held by syz-executor.1/10156: 1 lock held by syz-executor.2/10160: 1 lock held by syz-executor.3/10165: 3 locks held by syz-executor.1/10167: 1 lock held by syz-executor.4/10168: 1 lock held by syz-executor.4/10170: 2 locks held by syz-executor.0/10191: 1 lock held by syz-executor.2/10193: 2 locks held by syz-executor.0/10194: 1 lock held by syz-executor.2/10198: #0: ffff888029e74bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2688 1 lock held by syz-executor.4/10202: 1 lock held by syz-executor.4/10206: #0: ffff888029e74bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2688 1 lock held by syz-executor.1/10210: 1 lock held by syz-executor.3/10215: 3 locks held by syz-executor.3/10217: 1 lock held by syz-executor.1/10220: 1 lock held by syz-executor.2/10229: 1 lock held by syz-executor.2/10239: 1 lock held by syz-executor.4/10248: 2 locks held by syz-executor.3/10249: 1 lock held by syz-executor.1/10251: 1 lock held by syz-executor.0/10253: 1 lock held by syz-executor.3/10258: #0: ffff888029e74bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2688 1 lock held by syz-executor.4/10261: 2 locks held by syz-executor.2/10281: 2 locks held by syz-executor.0/10283: 1 lock held by syz-executor.1/10289: 2 locks held by syz-executor.4/10292: 1 lock held by syz-executor.2/10295: 3 locks held by syz-executor.4/10300: 1 lock held by syz-executor.1/10304: 1 lock held by syz-executor.3/10308: 1 lock held by syz-executor.2/10321: 1 lock held by syz-executor.2/10324: #0: ffff888029e74bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2688 1 lock held by syz-executor.1/10333: 1 lock held by syz-executor.4/10342: #0: ffff888029e74bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2688 1 lock held by syz-executor.0/10354: 1 lock held by syz-executor.3/10346: 1 lock held by syz-executor.2/10357: 3 locks held by syz-executor.2/10362: 1 lock held by syz-executor.0/10370: 1 lock held by syz-executor.1/10371: 1 lock held by syz-executor.3/10375: 3 locks held by syz-executor.0/10385: 1 lock held by syz-executor.4/10387: 3 locks held by syz-executor.4/10389: 1 lock held by syz-executor.0/10419: 1 lock held by syz-executor.3/10424: 1 lock held by syz-executor.0/10457: 1 lock held by syz-executor.2/10487: 1 lock held by syz-executor.0/10559: 2 locks held by syz-executor.3/10781: 1 lock held by syz-executor.4/10820: 2 locks held by syz-executor.2/10840: 1 lock held by syz-executor.3/10855: 1 lock held by syz-executor.2/10976: 1 lock held by syz-executor.4/10989: 1 lock held by syz-executor.4/10991: 1 lock held by syz-executor.2/11005: 1 lock held by syz-executor.2/11023: 1 lock held by syz-executor.4/11058: 1 lock held by syz-executor.2/11203: 2 locks held by syz-executor.2/11227: 1 lock held by syz-executor.0/11320: 1 lock held by syz-executor.2/11348: 1 lock held by syz-executor.1/11353: 1 lock held by syz-executor.3/11743: 4 locks held by syz-executor.0/11748: 1 lock held by syz-executor.1/11753: 1 lock held by syz-executor.4/11765: 1 lock held by syz-executor.3/11770: 2 locks held by syz-executor.0/11775: 1 lock held by syz-executor.4/11788: 2 locks held by syz-executor.3/11835: 2 locks held by syz-executor.3/11856: 1 lock held by syz-executor.3/11910: 4 locks held by syz-executor.0/12121: 3 locks held by syz-executor.0/12215: 4 locks held by syz-executor.0/12223: 2 locks held by syz-executor.1/12445: 4 locks held by syz-executor.0/12507: 3 locks held by syz-executor.0/12515: 4 locks held by syz-executor.1/12560: 3 locks held by syz-executor.0/12565: 2 locks held by syz-executor.2/12809: 4 locks held by syz-executor.0/12831: 2 locks held by syz-executor.3/13022: 5 locks held by syz-executor.1/13139: 2 locks held by syz-executor.2/13140: 4 locks held by syz-executor.1/13147: 3 locks held by syz-executor.2/13226: 2 locks held by syz-executor.2/13325: 2 locks held by syz-executor.1/13433: 4 locks held by syz-executor.2/13454: 4 locks held by syz-executor.2/13456: 4 locks held by syz-executor.0/13458: 4 locks held by syz-executor.0/13460: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.167-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:295 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7697 Comm: kworker/u4:8 Not tainted 5.15.167-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: 0x0 (bat_events) RIP: 0010:pick_next_task_fair+0x73/0x9c0 kernel/sched/fair.c:7508 Code: 89 fd 48 c1 ed 03 48 89 4c 24 18 0f b6 04 19 84 c0 0f 85 3f 02 00 00 48 8b 44 24 08 83 38 00 0f 84 f9 01 00 00 48 83 3c 24 00 <0f> 84 16 05 00 00 48 b8 00 00 00 00 00 fc ff df 80 7c 05 00 00 74 RSP: 0018:ffffc90003aa7b58 EFLAGS: 00000082 RAX: ffff8880b913a3d0 RBX: dffffc0000000000 RCX: 1ffff1101722747a RDX: ffffc90003aa7d20 RSI: ffff88801e51d940 RDI: ffff8880b913a300 RBP: 1ffff11003ca3b38 R08: dffffc0000000000 R09: fffffbfff1bd2c16 R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc90003aa7d20 R13: ffff8880b913a3c0 R14: 0000000000000000 R15: ffff88801e51d9c0 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056048156a680 CR3: 000000007e89c000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __pick_next_task kernel/sched/core.c:5647 [inline] pick_next_task kernel/sched/core.c:5755 [inline] __schedule+0x86d/0x45b0 kernel/sched/core.c:6337 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 worker_thread+0xf56/0x1280 kernel/workqueue.c:2478 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287