INFO: task syz.4.105:6176 blocked for more than 143 seconds. Not tainted 6.11.0-rc5-syzkaller-00310-ge8784b0aef62 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.105 state:D stack:21976 pid:6176 tgid:6176 ppid:5824 flags:0x00000004 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 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752 eventpoll_release_file+0xcb/0x1c0 fs/eventpoll.c:1106 eventpoll_release include/linux/eventpoll.h:53 [inline] __fput+0x6e0/0x8a0 fs/file_table.c:413 task_work_run+0x251/0x310 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb4e1779eb9 RSP: 002b:00007ffe8922e308 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fb4e1917a80 RCX: 00007fb4e1779eb9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fb4e1917a80 R08: 0000000000000006 R09: 00007ffe8922e5ff R10: 00000000003ffcec R11: 0000000000000246 R12: 0000000000037fa7 R13: 00007ffe8922e410 R14: 0000000000000032 R15: ffffffffffffffff Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 3 locks held by kworker/u8:4/63: #0: ffff88803024e148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88803024e148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc900015e7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc900015e7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4194 5 locks held by kworker/u8:5/136: 7 locks held by kworker/u8:7/1117: #0: ffff88801bae5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88801bae5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90004287d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90004287d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc7f0d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:594 #3: ffff8880302040e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #3: ffff8880302040e8 (&dev->mutex){....}-{3:3}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff8880302040e8 (&dev->mutex){....}-{3:3}, at: devlink_pernet_pre_exit+0x13b/0x440 net/devlink/core.c:506 #4: ffff888030205250 (&devlink->lock_key#26){+.+.}-{3:3}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff888030205250 (&devlink->lock_key#26){+.+.}-{3:3}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff888030205250 (&devlink->lock_key#26){+.+.}-{3:3}, at: devlink_pernet_pre_exit+0x14d/0x440 net/devlink/core.c:506 #5: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:773 #6: ffffffff8e93d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:296 [inline] #6: ffffffff8e93d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:958 3 locks held by kworker/u8:10/2564: #0: ffff88801ac81148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88801ac81148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90009757d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90009757d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 2 locks held by dhcpcd/4899: #0: ffff88805da56678 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0x119/0x790 net/netlink/af_netlink.c:2404 #1: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_dumpit+0x99/0x200 net/core/rtnetlink.c:6506 2 locks held by getty/4989: #0: ffff88823bd248a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 1 lock held by syz.4.26/5434: 1 lock held by syz.4.105/6176: #0: ffff888032fbbc68 (&ep->mtx){+.+.}-{3:3}, at: eventpoll_release_file+0xcb/0x1c0 fs/eventpoll.c:1106 2 locks held by syz.4.105/6178: 1 lock held by syz-executor/6808: #0: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz-executor/6822: #0: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz-executor/6825: #0: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz-executor/6892: #0: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 7 locks held by syz-executor/6895: #0: ffff88802f720420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2882 [inline] #0: ffff88802f720420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x227/0xc90 fs/read_write.c:586 #1: ffff8880330f7888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff888028299f08 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8f5262a8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff88805fa3b0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #4: ffff88805fa3b0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #4: ffff88805fa3b0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1292 #5: ffff88805fa3e250 (&devlink->lock_key#25){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672 #6: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:773 2 locks held by syz-executor/6943: #0: ffffffff8fc7f0d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c6/0x7b0 net/core/net_namespace.c:504 #1: ffffffff8fc8bc88 (rtnl_mutex){+.+.}-{3:3}, at: wg_netns_pre_exit+0x1f/0x1e0 drivers/net/wireguard/device.c:414 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc5-syzkaller-00310-ge8784b0aef62 #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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 2544 Comm: kworker/u8:9 Not tainted 6.11.0-rc5-syzkaller-00310-ge8784b0aef62 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:unwind_next_frame+0x1ac1/0x2a00 Code: 8b 2c 24 48 8b 74 24 10 0f 85 3e 0e 00 00 48 0f bf 03 48 01 c6 48 8d 55 40 48 89 ef e8 98 12 00 00 84 c0 74 28 e8 1f 4a 52 00 93 02 00 00 80 3d bb f7 c0 0e 01 0f 85 75 06 00 00 e8 08 4a 52 RSP: 0018:ffffc900095b74e8 EFLAGS: 00000293 RAX: ffffffff81414211 RBX: ffffffff911ddb10 RCX: ffff88802fdb8000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffc900095b7aa8 RBP: ffffc900095b75c0 R08: ffffffff8141554b R09: ffffffff814140bf R10: 0000000000000003 R11: ffff88802fdb8000 R12: ffffc900095b7ab0 R13: dffffc0000000000 R14: ffffc900095b7610 R15: 1ffff920012b6eb8 FS: 0000000000000000(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020008040 CR3: 000000000e734000 CR4: 0000000000350ef0 Call Trace: arch_stack_walk+0x151/0x1b0 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+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2252 [inline] slab_free mm/slub.c:4473 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4548 skb_kfree_head net/core/skbuff.c:1082 [inline] skb_free_head net/core/skbuff.c:1096 [inline] skb_release_data+0x64d/0x880 net/core/skbuff.c:1123 skb_release_all net/core/skbuff.c:1188 [inline] __kfree_skb net/core/skbuff.c:1202 [inline] sk_skb_reason_drop+0x1a5/0x3d0 net/core/skbuff.c:1240 kfree_skb_reason include/linux/skbuff.h:1260 [inline] kfree_skb include/linux/skbuff.h:1269 [inline] ieee80211_iface_work+0x272/0xf20 net/mac80211/iface.c:1644 cfg80211_wiphy_work+0x2dd/0x490 net/wireless/core.c:440 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2e/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd10 kernel/workqueue.c:3389 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