INFO: task kworker/0:6:1649 blocked for more than 143 seconds. Not tainted 5.19.0-rc1-syzkaller-00340-ge10b02ee5b6c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:6 state:D stack:26112 pid: 1649 ppid: 2 flags:0x00004000 Workqueue: events linkwatch_event Call Trace: context_switch kernel/sched/core.c:5116 [inline] __schedule+0xa00/0x4b30 kernel/sched/core.c:6428 schedule+0xd2/0x1f0 kernel/sched/core.c:6500 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6559 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0xa70/0x1350 kernel/locking/mutex.c:747 linkwatch_event+0xb/0x60 net/core/link_watch.c:263 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302 Showing all locks held in the system: 1 lock held by ksoftirqd/0/15: 1 lock held by khungtaskd/29: #0: ffffffff8bd867e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6491 2 locks held by kworker/u4:4/93: 1 lock held by hwrng/756: #0: ffffffff8c832c08 (reading_mutex){+.+.}-{3:3}, at: hwrng_fillfn+0x141/0x370 drivers/char/hw_random/core.c:503 2 locks held by getty/3290: #0: ffff88814a9dc098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc90002d162e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xe50/0x13c0 drivers/tty/n_tty.c:2124 3 locks held by kworker/1:2/16492: #0: ffff888011865d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888011865d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888011865d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888011865d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888011865d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888011865d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260 #1: ffffc9000e5d7da8 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264 #2: ffffffff8d58f2a8 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x83/0xe20 net/wireless/reg.c:2461 3 locks held by kworker/0:1/19967: #0: ffff8880260c6538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880260c6538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff8880260c6538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff8880260c6538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff8880260c6538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff8880260c6538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260 #1: ffffc900047afda8 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264 #2: ffffffff8d58f2a8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xe/0x20 net/ipv6/addrconf.c:4620 2 locks held by kworker/u4:1/27616: 5 locks held by kworker/u4:5/29254: #0: ffff8880119bd938 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880119bd938 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff8880119bd938 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff8880119bd938 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff8880119bd938 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff8880119bd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260 #1: ffffc9000fcefda8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264 #2: ffffffff8d57ab10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb00 net/core/net_namespace.c:556 #3: ffffffff8d58f2a8 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0x8e/0x590 net/core/dev.c:11332 #4: ffffffff8bd909a8 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x44/0x630 kernel/rcu/tree.c:4105 3 locks held by kworker/0:4/30439: #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260 #1: ffffc900048afda8 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264 #2: ffffffff8d58f2a8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:75 3 locks held by kworker/1:5/32653: #0: ffff8880260c6538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880260c6538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff8880260c6538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff8880260c6538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff8880260c6538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff8880260c6538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260 #1: ffffc9000d13fda8 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264 #2: ffffffff8d58f2a8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xe/0x20 net/ipv6/addrconf.c:4620 3 locks held by kworker/0:6/1649: #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260 #1: ffffc90003e8fda8 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264 #2: ffffffff8d58f2a8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:263 2 locks held by syz-executor.0/2663: #0: ffffffff8d57ab10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2f5/0x760 net/core/net_namespace.c:467 #1: ffffffff8d58f2a8 (rtnl_mutex){+.+.}-{3:3}, at: cangw_pernet_exit_batch+0x11/0xa0 net/can/gw.c:1250 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 5.19.0-rc1-syzkaller-00340-ge10b02ee5b6c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xc22/0xf90 kernel/hung_task.c:378 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 5.19.0-rc1-syzkaller-00340-ge10b02ee5b6c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:write_comp_data+0x85/0x90 kernel/kcov.c:255 Code: 00 00 4a 8d 34 dd 28 00 00 00 48 39 f2 72 1b 48 83 c7 01 48 89 38 4c 89 44 30 e0 4c 89 4c 30 e8 4c 89 54 30 f0 4a 89 4c d8 20 66 2e 0f 1f 84 00 00 00 00 00 48 8b 0c 24 40 0f b6 d6 40 0f b6 RSP: 0018:ffffc900001473c0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff81c781e5 RDX: ffff888011a83b00 RSI: 0000000000000100 RDI: 0000000000000006 RDX: ffff888011a83b00 RSI: 0000000000000100 RDI: 0000000000000006 RBP: ffff88823bde3000 R08: 0000000000000006 R09: ffff88823bde3000 R10: ffff88823bde25fe R11: 0000000000000001 R12: ffff88823bde25fe R13: ffff88823bde2000 R14: 00000000ffffffaf R15: ffff88823bde20b8 FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561d1487d680 CR3: 000000000ba8e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: for_each_canary mm/kfence/core.c:349 [inline] kfence_guarded_alloc mm/kfence/core.c:435 [inline] __kfence_alloc+0xf35/0x1540 mm/kfence/core.c:1039 kfence_alloc include/linux/kfence.h:128 [inline] slab_alloc_node mm/slub.c:3132 [inline] slab_alloc mm/slub.c:3222 [inline] __kmem_cache_alloc_lru mm/slub.c:3229 [inline] kmem_cache_alloc+0x389/0x3b0 mm/slub.c:3239 __skb_ext_alloc+0x19/0x80 net/core/skbuff.c:6317 skb_ext_add+0x5b0/0x790 net/core/skbuff.c:6412 nf_bridge_alloc include/net/netfilter/br_netfilter.h:12 [inline] br_nf_pre_routing_ipv6+0x10a/0x7b0 net/bridge/br_netfilter_ipv6.c:224 br_nf_pre_routing+0x14ad/0x1f00 net/bridge/br_netfilter_hooks.c:505 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_bridge_pre net/bridge/br_input.c:255 [inline] br_handle_frame+0x8df/0x1280 net/bridge/br_input.c:399 __netif_receive_skb_core+0xa13/0x3920 net/core/dev.c:5372 __netif_receive_skb_one_core+0xae/0x180 net/core/dev.c:5476 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5592 process_backlog+0x3a0/0x7c0 net/core/dev.c:5920 __napi_poll+0xb3/0x6e0 net/core/dev.c:6504 napi_poll net/core/dev.c:6571 [inline] net_rx_action+0x9c1/0xd90 net/core/dev.c:6682 __do_softirq+0x29b/0x9c2 kernel/softirq.c:571 run_ksoftirqd kernel/softirq.c:934 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:926 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 4a 8d 34 dd 28 00 00 lea 0x28(,%r11,8),%rsi 9: 00 a: 48 39 f2 cmp %rsi,%rdx d: 72 1b jb 0x2a f: 48 83 c7 01 add $0x1,%rdi 13: 48 89 38 mov %rdi,(%rax) 16: 4c 89 44 30 e0 mov %r8,-0x20(%rax,%rsi,1) 1b: 4c 89 4c 30 e8 mov %r9,-0x18(%rax,%rsi,1) 20: 4c 89 54 30 f0 mov %r10,-0x10(%rax,%rsi,1) 25: 4a 89 4c d8 20 mov %rcx,0x20(%rax,%r11,8) * 2a: c3 retq <-- trapping instruction 2b: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1) 32: 00 00 00 35: 48 8b 0c 24 mov (%rsp),%rcx 39: 40 0f b6 d6 movzbl %sil,%edx 3d: 40 rex 3e: 0f .byte 0xf 3f: b6 .byte 0xb6