INFO: task syz.2.21:5412 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-05591-g2a17bb8c204f #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.21 state:D stack:23864 pid:5412 tgid:5404 ppid:5246 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common kernel/locking/rwsem.c:1306 [inline] __down_write kernel/locking/rwsem.c:1315 [inline] down_write+0x1d7/0x220 kernel/locking/rwsem.c:1580 __super_lock fs/super.c:56 [inline] __super_lock_excl fs/super.c:71 [inline] deactivate_super+0xb5/0xf0 fs/super.c:505 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373 task_work_run+0x251/0x310 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa2f/0x27f0 kernel/exit.c:882 do_group_exit+0x207/0x2c0 kernel/exit.c:1031 get_signal+0x176f/0x1810 kernel/signal.c:2936 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:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f48ce17def9 RSP: 002b:00007f48cf028038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: fffffffffffffe00 RBX: 00007f48ce336058 RCX: 00007f48ce17def9 RDX: 0000000000000028 RSI: 00000000200000c0 RDI: 0000000000000004 RBP: 00007f48ce1f0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f48ce336058 R15: 00007ffde17b0dd8 INFO: task syz.2.106:5913 blocked for more than 144 seconds. Not tainted 6.11.0-syzkaller-05591-g2a17bb8c204f #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.106 state:D stack:24992 pid:5913 tgid:5912 ppid:5584 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 wb_wait_for_completion+0x166/0x290 fs/fs-writeback.c:216 sync_inodes_sb+0x293/0xb40 fs/fs-writeback.c:2799 iterate_supers+0xc8/0x190 fs/super.c:934 ksys_sync+0xbd/0x1c0 fs/sync.c:102 __do_sys_sync+0xe/0x20 fs/sync.c:113 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: 0033:0x7fb10837def9 RSP: 002b:00007fb109214038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007fb108535f80 RCX: 00007fb10837def9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fb1083f0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb108535f80 R15: 00007fff615d0898 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8e93e0f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #0: ffffffff8e93e0f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 4 locks held by kworker/u8:0/11: #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: ffffc90000107d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000107d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcb8210 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fcc4d08 (rtnl_mutex){+.+.}-{3:3}, at: wg_destruct+0x25/0x2e0 drivers/net/wireguard/device.c:246 1 lock held by khungtaskd/30: #0: ffffffff8e938b60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e938b60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e938b60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6701 3 locks held by kworker/u8:4/62: #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: ffffc900015d7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900015d7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcc4d08 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 2 locks held by kworker/u8:6/1295: 3 locks held by kworker/u8:10/2567: 2 locks held by getty/4993: #0: ffff88802e0140a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000312b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 1 lock held by syz.2.21/5412: #0: ffff8880602880e0 (&type->s_umount_key#68){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff8880602880e0 (&type->s_umount_key#68){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff8880602880e0 (&type->s_umount_key#68){++++}-{3:3}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 3 locks held by segctord/5409: #0: ffff8880b883e998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:560 #1: ffff8880b8828948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:989 #2: ffff8880607f19b8 (&sci->sc_wait_request){....}-{2:2}, at: nilfs_segctor_wakeup+0x36/0x350 fs/nilfs2/segment.c:2247 2 locks held by syz.2.106/5913: #0: ffff8880602880e0 (&type->s_umount_key#68){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880602880e0 (&type->s_umount_key#68){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff888142b9e7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:388 [inline] #1: ffff888142b9e7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xb40 fs/fs-writeback.c:2797 2 locks held by syz-executor/7346: #0: ffffffff8fcc4d08 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcc4d08 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 #1: ffffffff8e93e0f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #1: ffffffff8e93e0f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 3 locks held by kworker/u8:18/7545: #0: ffff88802d8b0948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88802d8b0948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90004537d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90004537d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcc4d08 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4196 1 lock held by syz-executor/7671: #0: ffffffff8fcc4d08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcc4d08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 4 locks held by syz-executor/7741: #0: ffff88803292c420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2930 [inline] #0: ffff88803292c420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679 #1: ffff88807d289488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff8880276251e8 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f561ca8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x1b4/0x890 drivers/net/netdevsim/bus.c:166 7 locks held by syz-executor/7745: #0: ffff88803292c420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2930 [inline] #0: ffff88803292c420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679 #1: ffff88805f943088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff8880276252d8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f561ca8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff888062fde0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #4: ffff888062fde0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #4: ffff888062fde0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1292 #5: ffff88807c2bb250 (&devlink->lock_key#23){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672 #6: ffffffff8fcc4d08 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:773 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-05591-g2a17bb8c204f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 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: 2567 Comm: kworker/u8:10 Not tainted 6.11.0-syzkaller-05591-g2a17bb8c204f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: events_unbound kfree_rcu_monitor RIP: 0010:should_resched arch/x86/include/asm/preempt.h:103 [inline] RIP: 0010:unwind_next_frame+0x18e6/0x22d0 arch/x86/kernel/unwind_orc.c:672 Code: 00 00 80 3d 45 30 ef 0c 01 75 40 80 3d c2 82 d8 11 00 75 37 c6 05 b9 82 d8 11 01 e9 21 fa ff ff bf 01 00 00 00 e8 0a c4 21 00 <65> 8b 0d ab 87 c2 7e b0 01 85 c9 75 73 e8 18 67 bf ff eb 6c 80 3d RSP: 0018:ffffc90009c374d0 EFLAGS: 00000297 RAX: 0000000080000001 RBX: ffffc90009c375b0 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffffc90009c30000 RDI: 0000000000000001 RBP: ffffc90009c375a0 R08: ffffc90009c37f20 R09: ffffc90009c375f0 R10: dffffc0000000000 R11: fffff52001386ec0 R12: dffffc0000000000 R13: ffffc90009c375a0 R14: ffffc90009c30000 R15: ffffc90009c37f30 FS: 0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f27ba507ab8 CR3: 0000000032468000 CR4: 0000000000350ef0 Call Trace: arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2343 [inline] slab_free_freelist_hook mm/slub.c:2372 [inline] slab_free_bulk mm/slub.c:4604 [inline] kmem_cache_free_bulk+0x2ea/0x530 mm/slub.c:4848 kfree_bulk include/linux/slab.h:767 [inline] kvfree_rcu_bulk+0x24b/0x4e0 kernel/rcu/tree.c:3385 kvfree_rcu_drain_ready kernel/rcu/tree.c:3559 [inline] kfree_rcu_monitor+0x8f5/0x990 kernel/rcu/tree.c:3631 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