INFO: task kworker/1:6:5893 blocked for more than 143 seconds. Not tainted 6.14.0-rc5-syzkaller-00016-g48a5eed9ad58 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:6 state:D stack:20304 pid:5893 tgid:5893 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events switchdev_deferred_process_work Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6857 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730 switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd30 kernel/workqueue.c:3400 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 3 locks held by kworker/u8:1/12: 1 lock held by khungtaskd/30: #0: ffffffff8eb38fa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb38fa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb38fa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 3 locks held by kworker/u8:3/53: 3 locks held by kworker/u8:4/68: 3 locks held by kworker/u8:5/1038: 2 locks held by syslogd/5188: 2 locks held by udevd/5206: 2 locks held by getty/5587: #0: ffff888035c520a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211 2 locks held by kworker/0:5/5891: 3 locks held by kworker/1:6/5893: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc9000434fc60 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000434fc60 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffffffff8fed56c8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 3 locks held by kworker/u8:7/5910: 4 locks held by kworker/1:7/5947: 3 locks held by kworker/u8:10/9163: 7 locks held by kworker/u8:12/9168: 2 locks held by kworker/u8:13/9169: #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc9000b5afc60 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000b5afc60 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 3 locks held by kworker/u8:16/9172: 3 locks held by kworker/u8:17/9173: 3 locks held by kworker/u8:18/9174: #0: ffff88814d3ca948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88814d3ca948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc90003f07c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003f07c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffffffff8fed56c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #2: ffffffff8fed56c8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x10e/0x16a0 net/ipv6/addrconf.c:4190 6 locks held by kworker/0:9/9739: 2 locks held by syz-executor/12955: 1 lock held by syz-executor/13245: #0: ffffffff8fed56c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fed56c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 4 locks held by kworker/1:8/14435: #0: ffff88801b081d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b081d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc9000b47fc60 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000b47fc60 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffffffff8fed56c8 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x99/0xfb0 net/wireless/reg.c:2480 #3: ffff88804fe48768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6061 [inline] #3: ffff88804fe48768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_leave_invalid_chans net/wireless/reg.c:2468 [inline] #3: ffff88804fe48768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_check_chans_work+0x164/0xfb0 net/wireless/reg.c:2483 1 lock held by syz-executor/15466: #0: ffffffff8fed56c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fed56c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 2 locks held by syz-executor/16012: 6 locks held by syz.9.1451/16243: 1 lock held by modprobe/16285: 3 locks held by kworker/0:10/16287: 4 locks held by syz-executor/16289: 2 locks held by kworker/1:11/16290: 2 locks held by dhcpcd-run-hook/16292: 2 locks held by syz-executor/16295: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc5-syzkaller-00016-g48a5eed9ad58 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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:236 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:399 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 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: 9168 Comm: kworker/u8:12 Not tainted 6.14.0-rc5-syzkaller-00016-g48a5eed9ad58 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: bat_events batadv_tt_purge RIP: 0010:preempt_count_add+0x34/0x190 kernel/sched/core.c:5852 Code: fb 48 c7 c0 80 09 65 9a 48 c1 e8 03 49 bf 00 00 00 00 00 fc ff df 42 0f b6 04 38 84 c0 0f 85 ed 00 00 00 83 3d dc a7 d5 18 00 <75> 07 65 8b 05 db 74 74 7e 65 01 1d d4 74 74 7e 48 c7 c0 80 09 65 RSP: 0018:ffffc90000006ab0 EFLAGS: 00000246 RAX: 0000000000000004 RBX: 0000000000000001 RCX: ffffffff9a650903 RDX: dffffc0000000000 RSI: ffffffff81ad4a18 RDI: 0000000000000001 RBP: ffffc90000006bd8 R08: 0000000000000000 R09: ffffc90000006c90 R10: ffffc90000006bf0 R11: ffffffff81ad4ae0 R12: dffffc0000000000 R13: ffffc90000006ba0 R14: ffffffff81ad4a18 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb3376d56e8 CR3: 000000000e938000 CR4: 00000000003526f0 DR0: 000000000000000c DR1: 0000000000000002 DR2: fffffffffffffffb DR3: 3e00000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0xb0/0x22d0 arch/x86/kernel/unwind_orc.c:479 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 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4171 skb_clone+0x20c/0x390 net/core/skbuff.c:1994 deliver_clone net/bridge/br_forward.c:125 [inline] br_flood+0x3df/0x680 net/bridge/br_forward.c:249 br_handle_frame_finish+0x18d2/0x2000 net/bridge/br_input.c:220 br_nf_hook_thresh+0x472/0x590 br_nf_pre_routing_finish_ipv6+0xaa0/0xdd0 NF_HOOK include/linux/netfilter.h:314 [inline] br_nf_pre_routing_ipv6+0x379/0x770 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:282 [inline] br_handle_frame+0x9f3/0x1530 net/bridge/br_input.c:433 __netif_receive_skb_core+0x13e7/0x4540 net/core/dev.c:5787 __netif_receive_skb_one_core net/core/dev.c:5891 [inline] __netif_receive_skb+0x12f/0x650 net/core/dev.c:6006 process_backlog+0x662/0x15b0 net/core/dev.c:6354 __napi_poll+0xcb/0x490 net/core/dev.c:7188 napi_poll net/core/dev.c:7257 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7379 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 do_softirq+0x11b/0x1e0 kernel/softirq.c:462 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:389 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_tt_local_purge+0x2a0/0x340 net/batman-adv/translation-table.c:1315 batadv_tt_purge+0x35/0xa40 net/batman-adv/translation-table.c:3509 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd30 kernel/workqueue.c:3400 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244