INFO: task syz.4.1357:10385 blocked for more than 143 seconds. Not tainted 6.12.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.1357 state:D stack:23808 pid:10385 tgid:10385 ppid:8985 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x18af/0x4bd0 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6782 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6839 rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1d7/0x220 kernel/locking/rwsem.c:1578 mmap_write_lock include/linux/mmap_lock.h:106 [inline] exit_mmap+0x2bd/0xc40 mm/mmap.c:1882 __mmput+0x115/0x390 kernel/fork.c:1347 exit_mm+0x220/0x310 kernel/exit.c:571 do_exit+0x9b2/0x28e0 kernel/exit.c:926 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 __do_sys_exit_group kernel/exit.c:1099 [inline] __se_sys_exit_group kernel/exit.c:1097 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1097 x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232 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: 0033:0x7f9eac97dff9 RSP: 002b:00007ffef6a38e98 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9eac97dff9 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffef6a38eec R08: 00007ffef6a38f7f R09: 000000000004adcf R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000032 R13: 000000000004adcf R14: 000000000004ad89 R15: 00007ffef6a38f40 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8e93d3b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93d3b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 3 locks held by kworker/u8:0/11: #0: ffff88801ac81148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac81148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000107d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000107d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 3 locks held by kworker/u8:1/12: #0: ffff88814b783148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88814b783148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000117d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000117d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4196 1 lock held by khungtaskd/30: #0: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 2 locks held by getty/4980: #0: ffff88802ece50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 5 locks held by kworker/u8:10/7631: #0: ffff88801bae5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801bae5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90009e5fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] ffffc90009e5fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcc6350 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe9/0xaa0 net/core/dev.c:11934 #4: ffffffff8e93d3b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #4: ffffffff8e93d3b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 3 locks held by syz.1.1164/9802: 1 lock held by syz.5.1347/10367: #0: ffff88801ac71e18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:106 [inline] #0: ffff88801ac71e18 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x2bd/0xc40 mm/mmap.c:1882 1 lock held by syz.3.1356/10384: #0: ffff88801ac71498 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:106 [inline] #0: ffff88801ac71498 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x2bd/0xc40 mm/mmap.c:1882 1 lock held by syz.4.1357/10385: #0: ffff88807b3eb118 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:106 [inline] #0: ffff88807b3eb118 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x2bd/0xc40 mm/mmap.c:1882 1 lock held by syz-executor/12036: #0: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6672 1 lock held by syz-executor/12145: #0: ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] ffffffff8fcd2e48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6672 10 locks held by syz.0.1987/12388: #0: ffff8880b863ea98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:598 #1: ffff8880b8628948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x387/0x7a0 kernel/sched/psi.c:975 #2: ffffffff9a6213b8 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_deactivate+0x158/0x390 lib/debugobjects.c:763 #3: ffff88804b19b958 (&new_ns->poll){....}-{2:2}, at: __wake_up_common_lock+0x25/0x1e0 kernel/sched/wait.c:105 #4: ffffe8ffffc8e108 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x387/0x7a0 kernel/sched/psi.c:975 #5: ffff88801ac98018 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x759/0xf50 #6: ffff888027386418 (&p->pi_lock){-.-.}-{2:2}, at: class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline] #6: ffff888027386418 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xbe/0x14b0 kernel/sched/core.c:4165 #7: ffff8880b863ea98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:598 #8: ffff8880b8628948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_change+0xed/0x270 kernel/sched/psi.c:912 #9: ffff88801ac98018 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x759/0xf50 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 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+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/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 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.12.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: btrfs-endio-write btrfs_work_helper RIP: 0010:alloc_lock_chain kernel/locking/lockdep.c:3716 [inline] RIP: 0010:add_chain_cache kernel/locking/lockdep.c:3742 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3851 [inline] RIP: 0010:validate_chain+0x333/0x5920 kernel/locking/lockdep.c:3872 Code: 0f 87 5c 02 00 00 48 63 d8 48 89 d8 48 c1 e8 06 48 8d 3c c5 c0 16 e1 93 be 08 00 00 00 e8 a5 9e 8d 00 48 0f ab 1d ed 05 70 12 <48> c1 e3 05 48 c7 c6 60 9d 2c 94 48 01 de 0f 84 24 02 00 00 48 89 RSP: 0018:ffffc90000bd61c0 EFLAGS: 00000056 RAX: 0000000000000701 RBX: 000000000001c6c6 RCX: ffffffff817110cb RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffff93e14f98 RBP: ffffc90000bd64c0 R08: ffffffff93e14f9f R09: 1ffffffff27c29f3 R10: dffffc0000000000 R11: fffffbfff27c29f4 R12: dffffc0000000000 R13: ffff8880216e2a18 R14: 905a31c11c6fa304 R15: ffff8880216e2a18 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020009000 CR3: 000000007db12000 CR4: 0000000000350ef0 Call Trace: __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] __filemap_add_folio+0x8a8/0x1b90 mm/filemap.c:880 filemap_add_folio+0x157/0x650 mm/filemap.c:972 attach_eb_folio_to_filemap fs/btrfs/extent_io.c:2866 [inline] alloc_extent_buffer+0x64c/0x2740 fs/btrfs/extent_io.c:3002 btrfs_init_new_buffer fs/btrfs/extent-tree.c:5042 [inline] btrfs_alloc_tree_block+0x28e/0x1440 fs/btrfs/extent-tree.c:5155 btrfs_force_cow_block+0x526/0x1da0 fs/btrfs/ctree.c:573 btrfs_cow_block+0x35e/0xa40 fs/btrfs/ctree.c:754 btrfs_search_slot+0xbdd/0x30d0 fs/btrfs/ctree.c:2116 btrfs_lookup_file_extent+0x14c/0x210 fs/btrfs/file-item.c:267 btrfs_drop_extents+0x453/0x33e0 fs/btrfs/file.c:251 insert_reserved_file_extent+0x384/0xd20 fs/btrfs/inode.c:2935 insert_ordered_extent_file_extent+0x466/0x650 fs/btrfs/inode.c:3040 btrfs_finish_one_ordered+0x89e/0x17b0 fs/btrfs/inode.c:3153 btrfs_work_helper+0x392/0xc50 fs/btrfs/async-thread.c:314 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244