INFO: task syz-executor.0:15189 blocked for more than 143 seconds. Not tainted 5.15.152-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:22680 pid:15189 ppid: 10691 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 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:2933 [inline] ext4_da_write_begin+0x228/0xb60 fs/ext4/inode.c:2960 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:2875 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:172 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208 irqentry_exit_to_user_mode+0x5/0x40 kernel/entry/common.c:314 exc_general_protection+0x358/0x4f0 arch/x86/kernel/traps.c:562 asm_exc_general_protection+0x22/0x30 arch/x86/include/asm/idtentry.h:562 RIP: 0033:0x7f3154619db1 RSP: 002b:00000000200004b0 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f3154747f80 RCX: 00007f3154619da9 RDX: 00000000200004c0 RSI: 00000000200004b0 RDI: 0000000000080000 RBP: 00007f315466647a R08: 0000000020000540 R09: 0000000020000540 R10: 0000000020000500 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000000b R14: 00007f3154747f80 R15: 00007ffc00004ae8 Showing all locks held in the system: 3 locks held by kworker/u4:0/9: 2 locks held by kworker/0:1/13: #0: ffff888011c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90000d27d20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 1 lock held by khungtaskd/27: #0: ffffffff8c91f720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 5 locks held by kworker/u4:4/1433: #0: ffff888011dcd138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90005bffd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8d9cfe50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:558 #3: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock_unregistering net/core/dev.c:11576 [inline] #3: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0x1ac/0x3f0 net/core/dev.c:11614 #4: ffffffff8c923ce8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #4: ffffffff8c923ce8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845 1 lock held by dhcpcd/3175: #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5626 2 locks held by getty/3258: #0: ffff8880248ec098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002bab2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 3 locks held by kworker/1:3/3528: #0: ffff888011c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900030d7d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 3 locks held by kworker/1:5/3562: #0: ffff888011c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900046a7d20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74 4 locks held by kworker/u4:5/3657: 3 locks held by kworker/u4:8/6346: 3 locks held by syz-executor.0/15189: #0: ffff888024b4c460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff8880597a7198 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline] #1: ffff8880597a7198 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xa0/0x360 fs/ext4/file.c:262 #2: ffff888024b4c0e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x1d/0xb0 fs/fs-writeback.c:2729 2 locks held by syz-executor.1/15550: 1 lock held by syz-executor.0/15554: 2 locks held by syz-executor.4/15559: 3 locks held by syz-executor.1/15566: 1 lock held by syz-executor.3/15580: 2 locks held by syz-executor.3/15594: 1 lock held by syz-executor.1/15595: 1 lock held by syz-executor.0/15603: 3 locks held by syz-executor.4/15612: 1 lock held by syz-executor.0/15616: 2 locks held by syz-executor.1/15621: 1 lock held by syz-executor.4/15631: 3 locks held by syz-executor.3/15639: 3 locks held by syz-executor.4/15648: 1 lock held by syz-executor.1/15650: 3 locks held by syz-executor.0/15657: 2 locks held by syz-executor.3/15661: 2 locks held by syz-executor.4/15667: 1 lock held by syz-executor.3/15676: 2 locks held by syz-executor.1/15677: 1 lock held by syz-executor.0/15684: 1 lock held by syz-executor.4/15889: 1 lock held by syz-executor.0/16088: 6 locks held by syz-executor.2/16822: #0: ffff88807f106460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x29a/0xe50 fs/read_write.c:590 #1: ffff88802050b088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:287 #2: ffff88801a978578 (kn->active#234){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:288 #3: ffffffff8d357a88 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x1b0/0x910 drivers/net/netdevsim/bus.c:295 #4: ffff888077dbb178 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #4: ffff888077dbb178 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:954 #5: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:310 [inline] #5: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: nsim_create+0x2ec/0x3e0 drivers/net/netdevsim/netdev.c:365 4 locks held by syz-executor.4/16824: #0: ffff88807f106460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x29a/0xe50 fs/read_write.c:590 #1: ffff88801b71b488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:287 #2: ffff88801a978660 (kn->active#233){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:288 #3: ffffffff8d357a88 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xf1/0x470 drivers/net/netdevsim/bus.c:344 1 lock held by syz-executor.0/17228: 1 lock held by syz-executor.1/17258: #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5626 1 lock held by syz-executor.0/17276: 1 lock held by syz-executor.0/17385: 1 lock held by syz-executor.3/17391: 2 locks held by syz-executor.3/17414: 1 lock held by syz-executor.0/17445: 1 lock held by syz-executor.0/17448: #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:699 [inline] #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3435 2 locks held by syz-executor.3/17470: 2 locks held by syz-executor.3/17475: 1 lock held by syz-executor.2/17486: #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5626 1 lock held by syz-executor.4/17487: #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d9dba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5626 4 locks held by syz-executor.3/17510: 4 locks held by syz-executor.3/17536: 3 locks held by syz-executor.3/17540: 4 locks held by syz-executor.3/17547: 2 locks held by syz-executor.3/17552: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.152-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb 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:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 144 Comm: kworker/u4:1 Not tainted 5.15.152-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:batadv_nc_purge_paths+0xf4/0x3b0 net/batman-adv/network-coding.c:447 Code: 48 8b 4c 24 18 48 8b 44 24 10 48 89 cf 48 c1 e7 06 48 03 38 48 89 7c 24 50 e8 c8 b6 2b 00 48 89 e8 48 c1 e8 03 42 80 3c 28 00 <74> 08 48 89 ef e8 32 68 d0 f7 4c 8b 75 00 4d 85 f6 0f 84 f4 01 00 RSP: 0018:ffffc9000153fb60 EFLAGS: 00000246 RAX: 1ffff1100fd58200 RBX: ffffffff89f990c0 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc9000153fae0 RBP: ffff88807eac1000 R08: dffffc0000000000 R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000000000400 R13: dffffc0000000000 R14: ffff8880236ad140 R15: ffff8880236ad150 FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc41109f800 CR3: 000000001d570000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: batadv_nc_worker+0x2cf/0x5b0 net/batman-adv/network-coding.c:724 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298