INFO: task syz.9.64:5302 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.9.64 state:D stack:21960 pid:5302 ppid:5077 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 io_schedule+0x7c/0xd0 kernel/sched/core.c:8797 __lock_metapage fs/jfs/jfs_metapage.c:50 [inline] lock_metapage+0x1e8/0x310 fs/jfs/jfs_metapage.c:64 __get_metapage+0x4c6/0xfa0 fs/jfs/jfs_metapage.c:639 xtSplitPage+0x238/0x1c10 fs/jfs/jfs_xtree.c:974 xtSplitUp+0x293/0x1c20 fs/jfs/jfs_xtree.c:771 xtInsert+0x455/0xbb0 fs/jfs/jfs_xtree.c:593 extAlloc+0x9f6/0xf30 fs/jfs/jfs_extent.c:145 jfs_get_block+0x343/0xab0 fs/jfs/inode.c:254 __block_write_begin_int+0x54b/0x1a70 fs/buffer.c:1991 __block_write_begin fs/buffer.c:2041 [inline] block_write_begin+0x96/0x1e0 fs/buffer.c:2102 jfs_write_begin+0x31/0x70 fs/jfs/inode.c:310 generic_perform_write+0x2f7/0x5a0 mm/filemap.c:3862 __generic_file_write_iter+0x148/0x2a0 mm/filemap.c:3960 generic_file_write_iter+0xab/0x2e0 mm/filemap.c:3989 __kernel_write_iter+0x26d/0x630 fs/read_write.c:517 dump_emit_page fs/coredump.c:950 [inline] dump_user_range+0x3ea/0x7f0 fs/coredump.c:977 elf_core_dump+0x2f77/0x3490 fs/binfmt_elf.c:2354 do_coredump+0x15ff/0x22b0 fs/coredump.c:824 get_signal+0x10aa/0x1350 kernel/signal.c:2857 arch_do_signal_or_restart+0xb7/0x1240 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:316 exc_page_fault+0x88/0x100 arch/x86/mm/fault.c:1490 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f89ec98f751 RSP: 002b:00000000fffffe60 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f89ecbe5fa0 RCX: 00007f89ec98f749 RDX: 0000000000000000 RSI: 00000000fffffe60 RDI: 0000000000040000 RBP: 00007f89eca13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f89ecbe5fa0 R14: 00007f89ecbe5fa0 R15: 0000000000000006 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8c92bab0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8c92c2d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8c92b120 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8c92b120 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8c92b120 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 3 locks held by kworker/u4:3/46: 5 locks held by kworker/u4:4/56: #0: ffff888017616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc90001577d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffffffff8db2e6d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:594 #3: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe5/0xa50 net/core/dev.c:11489 #4: ffffffff8c930df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #4: ffffffff8c930df8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x455/0x830 kernel/rcu/tree_exp.h:962 2 locks held by dhcpcd/3930: #0: ffffffff8db214e8 (vlan_ioctl_mutex){+.+.}-{3:3}, at: sock_ioctl+0x273/0x6e0 net/socket.c:1283 #1: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: vlan_ioctl_handler+0xd2/0x5f0 net/8021q/vlan.c:580 2 locks held by getty/4027: #0: ffff88814d1d0098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198 3 locks held by kworker/u4:5/4321: 2 locks held by kworker/0:3/4345: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc90004357d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 4 locks held by kworker/u4:8/4575: #0: ffff88801be6d138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc900038a7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffff88805beb40e0 (&type->s_umount_key#53){++++}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:415 #3: ffff888070199448 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x1c7/0x520 fs/jfs/inode.c:108 3 locks held by kworker/0:15/5281: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc90004847d00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:104 3 locks held by syz-executor/5299: #0: ffff88805beb4460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:402 #1: ffff888055c0bd00 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline] #1: ffff888055c0bd00 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: do_unlinkat+0x178/0x560 fs/namei.c:4381 #2: ffff888070199800 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #2: ffff888070199800 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: vfs_unlink+0xee/0x600 fs/namei.c:4319 4 locks held by syz.9.64/5302: #0: ffff888024d22460 (sb_writers#13){.+.+}-{0:0}, at: do_coredump+0x15de/0x22b0 fs/coredump.c:823 #1: ffff888057872a80 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #1: ffff888057872a80 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: generic_file_write_iter+0x7f/0x2e0 mm/filemap.c:3986 #2: ffff888057872638 (&jfs_ip->rdwrlock#2){+.+.}-{3:3}, at: jfs_get_block+0x13e/0xab0 fs/jfs/inode.c:219 #3: ffff8880578726c8 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: extAlloc+0x10b/0xf30 fs/jfs/jfs_extent.c:81 4 locks held by syz.4.89/5554: #0: ffff88805beb4460 (sb_writers#13){.+.+}-{0:0}, at: do_coredump+0x15de/0x22b0 fs/coredump.c:823 #1: ffff888070199800 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #1: ffff888070199800 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: generic_file_write_iter+0x7f/0x2e0 mm/filemap.c:3986 #2: ffff8880701993b8 (&jfs_ip->rdwrlock#2){+.+.}-{3:3}, at: jfs_get_block+0x13e/0xab0 fs/jfs/inode.c:219 #3: ffff888070199448 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: extAlloc+0x10b/0xf30 fs/jfs/jfs_extent.c:81 3 locks held by kworker/u4:10/5738: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc9000527fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263 1 lock held by udevd/5827: 1 lock held by syz-executor/6516: #0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6147 1 lock held by syz-executor/6556: #0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6147 1 lock held by syz-executor/6572: #0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8db3b3a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6147 2 locks held by syz.4.254/6619: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xeee/0xf30 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 6621 Comm: syz.9.255 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0033:0x7f406e4509eb Code: cd 48 01 c1 49 39 4f 08 72 4c 8d 4d ff 85 ed 74 33 66 0f 1f 44 00 00 48 39 f0 72 1b 4d 8b 07 49 89 c1 49 29 f1 47 0f b6 0c 08 <45> 84 c9 74 08 45 88 0c 00 49 8b 47 10 48 83 c0 01 49 89 47 10 83 RSP: 002b:00007ffe9045c4f0 EFLAGS: 00000206 RAX: 00000000002bea2e RBX: 00007ffe9045c590 RCX: 0000000000000085 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00007ffe9045c630 RBP: 0000000000000102 R08: 00007f40657ff000 R09: 0000000000000000 R10: 0000000000000000 R11: 00007ffe9045c5a0 R12: 0000000000000001 R13: 00007f406e62fc40 R14: 0000000000000000 R15: 00007ffe9045c630 FS: 000055558d0cb500 GS: 0000000000000000