INFO: task syz.4.298:8636 blocked for more than 143 seconds. Not tainted 6.13.0-rc3-syzkaller-00017-gf44d154d6e3d #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.298 state:D stack:23488 pid:8636 tgid:8588 ppid:5827 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905 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 do_remount fs/namespace.c:3044 [inline] path_mount+0xbdb/0xfa0 fs/namespace.c:3826 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4057 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034 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: 0033:0x7f17da985d19 RSP: 002b:00007f17db793038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f17dab76160 RCX: 00007f17da985d19 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000000 RBP: 00007f17daa01a20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000002012024 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f17dab76160 R15: 00007fffc934dc58 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 3 locks held by kworker/u8:1/12: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc90000117d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000117d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fca0508 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:281 1 lock held by khungtaskd/30: #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 2 locks held by kworker/0:3/1212: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc90003f9fd00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90003f9fd00 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 1 lock held by dhcpcd/5489: #0: ffffffff8fca0508 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline] #0: ffffffff8fca0508 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_deladdr+0x1a1/0x7b0 net/ipv4/devinet.c:679 2 locks held by getty/5575: #0: ffff8880358420a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000330b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:6/5899: 4 locks held by kworker/u8:10/6809: #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9000440fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000440fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fc94050 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x16a/0xd50 net/core/net_namespace.c:602 #3: ffffffff8fca0508 (rtnl_mutex){+.+.}-{4:4}, at: cangw_pernet_exit_batch+0x20/0x90 net/can/gw.c:1257 1 lock held by dhcpcd/8307: #0: ffff888079aab208 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline] #0: ffff888079aab208 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: __sock_release net/socket.c:639 [inline] #0: ffff888079aab208 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1408 5 locks held by syz.4.298/8589: #0: ffff88823bfea420 (sb_writers#25){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff8880579fb5c8 (&sb->s_type->i_mutex_key#31){++++}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline] #1: ffff8880579fb5c8 (&sb->s_type->i_mutex_key#31){++++}-{4:4}, at: do_truncate+0x20c/0x310 fs/open.c:63 #2: ffff888060600a38 (&c->snapshot_create_lock){.+.+}-{4:4}, at: bch2_truncate+0x166/0x2d0 fs/bcachefs/io_misc.c:292 #3: ffff888060604398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #3: ffff888060604398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #3: ffff888060604398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7e1/0xd30 fs/bcachefs/btree_iter.c:3228 #4: ffff8880606266d0 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x682/0x14e0 fs/bcachefs/btree_update_interior.c:1197 3 locks held by syz.4.298/8619: #0: ffff88823bfea0e0 (&type->s_umount_key#56){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88823bfea0e0 (&type->s_umount_key#56){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff888060604398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #1: ffff888060604398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #1: ffff888060604398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7e1/0xd30 fs/bcachefs/btree_iter.c:3228 #2: ffff8880606266d0 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x682/0x14e0 fs/bcachefs/btree_update_interior.c:1197 1 lock held by syz.4.298/8636: #0: ffff88823bfea0e0 (&type->s_umount_key#56){++++}-{4:4}, at: do_remount fs/namespace.c:3044 [inline] #0: ffff88823bfea0e0 (&type->s_umount_key#56){++++}-{4:4}, at: path_mount+0xbdb/0xfa0 fs/namespace.c:3826 2 locks held by syz-executor/10272: #0: ffff88802b020d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:480 [inline] #0: ffff88802b020d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2697 #1: ffff88802b020078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x5c8/0x11c0 net/bluetooth/hci_sync.c:5200 1 lock held by syz.4.621/11235: #0: ffff88823bfea0e0 (&type->s_umount_key#56){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88823bfea0e0 (&type->s_umount_key#56){++++}-{4:4}, at: super_lock+0x196/0x400 fs/super.c:120 1 lock held by syz-executor/11583: #0: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 1 lock held by syz-executor/11624: #0: ffffffff8fc94050 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512 2 locks held by dhcpcd/11737: #0: ffff8880574f9408 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline] #0: ffff8880574f9408 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: __sock_release net/socket.c:639 [inline] #0: ffff8880574f9408 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1408 #1: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #1: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc3-syzkaller-00017-gf44d154d6e3d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 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:234 [inline] watchdog+0xff6/0x1040 kernel/hung_task.c:397 kthread+0x2f0/0x390 kernel/kthread.c:389 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 11502 Comm: syz-executor Not tainted 6.13.0-rc3-syzkaller-00017-gf44d154d6e3d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 RIP: 0010:check_preemption_disabled+0x60/0x120 lib/smp_processor_id.c:19 Code: 00 48 3b 44 24 08 0f 85 ce 00 00 00 89 d8 48 83 c4 10 5b 41 5c 41 5e 41 5f c3 cc cc cc cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 04 24 00 02 00 00 74 c5 49 89 f6 49 89 ff 65 4c 8b 24 25 80 d4 RSP: 0018:ffffc900054a7608 EFLAGS: 00000046 RAX: 0000000080000000 RBX: 0000000000000000 RCX: ffff88802c54a8d8 RDX: dffffc0000000000 RSI: ffffffff8c0aa960 RDI: ffffffff8c5ed820 RBP: ffffc900054a77a0 R08: ffffffff94270887 R09: 1ffffffff284e110 R10: dffffc0000000000 R11: fffffbfff284e111 R12: 1ffff92000a94ed0 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055b53826bcf0 CR3: 000000002f0de000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:467 [inline] lock_acquire+0x1fd/0x550 kernel/locking/lockdep.c:5851 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ext_get+0x3d/0x2a0 mm/page_ext.c:525 __reset_page_owner+0x30/0x430 mm/page_owner.c:290 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_page+0xd2c/0x1000 mm/page_alloc.c:2657 vfree+0x186/0x2e0 mm/vmalloc.c:3382 kcov_put kernel/kcov.c:439 [inline] kcov_close+0x28/0x50 kernel/kcov.c:535 __fput+0x23c/0xa50 fs/file_table.c:450 task_work_run+0x24f/0x310 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xa2f/0x28e0 kernel/exit.c:938 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 get_signal+0x16b2/0x1750 kernel/signal.c:3017 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5112987bac Code: Unable to access opcode bytes at 0x7f5112987b82. RSP: 002b:00007ffee76d5f90 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: 0000000000000028 RBX: 00007f51136a4620 RCX: 00007f5112987bac RDX: 0000000000000028 RSI: 00007f51136a4670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffee76d5fe4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f51136a4670 R15: 0000000000000000