INFO: task kworker/u8:0:12 blocked for more than 163 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:0 state:D stack:23448 pid:12 tgid:12 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7026 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121 __flush_workqueue+0x3e2/0x1230 kernel/workqueue.c:4029 rxrpc_destroy_all_locals+0x40/0x180 net/rxrpc/local_object.c:475 rxrpc_exit_net+0x8b/0xc0 net/rxrpc/net_ns.c:115 ops_exit_list net/core/net_namespace.c:199 [inline] ops_undo_list+0x2ee/0xab0 net/core/net_namespace.c:252 cleanup_net+0x41b/0x8b0 net/core/net_namespace.c:695 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 3 locks held by kworker/u8:0/12: #0: ffff88801ba9f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238 #1: ffffc90000117d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239 #2: ffffffff900e6b30 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x8b0 net/core/net_namespace.c:669 1 lock held by khungtaskd/31: #0: ffffffff8e3c42e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3c42e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e3c42e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 2 locks held by getty/5593: #0: ffff8880310130a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by syz.1.109/6586: #0: ffffffff900e6b30 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x2d6/0x690 net/core/net_namespace.c:576 1 lock held by syz.0.175/6899: #0: ffffffff900e6b30 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x2d6/0x690 net/core/net_namespace.c:576 1 lock held by syz.5.260/7453: #0: ffffffff900e6b30 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x2d6/0x690 net/core/net_namespace.c:576 2 locks held by kworker/u10:7/7875: #0: ffff888146ab3948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238 #1: ffffc9000af77d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239 1 lock held by syz.4.366/7945: #0: ffffffff900e6b30 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x2d6/0x690 net/core/net_namespace.c:576 1 lock held by syz.7.449/8466: #0: ffffffff900e6b30 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x2d6/0x690 net/core/net_namespace.c:576 1 lock held by syz.3.523/8643: #0: ffffffff900e6b30 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x2d6/0x690 net/core/net_namespace.c:576 1 lock held by syz.6.542/8718: #0: ffffffff900e6b30 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x2d6/0x690 net/core/net_namespace.c:576 1 lock held by syz.8.572/8860: #0: ffff8880850ba488 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline] #0: ffff8880850ba488 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:661 1 lock held by syz.9.687/9472: #0: ffffffff900e6b30 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x2d6/0x690 net/core/net_namespace.c:576 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf3f/0x1170 kernel/hung_task.c:495 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9192 Comm: kworker/u10:33 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:56 [inline] RIP: 0010:stack_access_ok+0x53/0x200 arch/x86/kernel/unwind_orc.c:393 Code: 83 ec 08 80 3c 02 00 0f 85 94 01 00 00 4c 8d 6b 10 4c 8b 7b 08 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02 00 <0f> 85 52 01 00 00 48 89 da 48 8b 4b 10 48 b8 00 00 00 00 00 fc ff RSP: 0018:ffffc90000006f50 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffffc90000007000 RCX: ffffffff917d2374 RDX: 1ffff92000000e02 RSI: ffffc9002a787c20 RDI: ffffc90000007000 RBP: ffffc9002a787c20 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 000000000005f656 R12: 0000000000000008 R13: ffffc90000007010 R14: ffffc90000007008 R15: ffffc9002a780000 FS: 0000000000000000(0000) GS:ffff8881249e1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4d29bb3ad8 CR3: 00000000760c6000 CR4: 00000000003526f0 Call Trace: deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] unwind_next_frame+0x15c5/0x20a0 arch/x86/kernel/unwind_orc.c:648 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2530 [inline] slab_free mm/slub.c:6619 [inline] kfree+0x2b8/0x6d0 mm/slub.c:6826 ieee80211_inform_bss+0x77c/0x1140 net/mac80211/scan.c:160 rdev_inform_bss net/wireless/rdev-ops.h:418 [inline] cfg80211_inform_single_bss_data+0x8ea/0x1df0 net/wireless/scan.c:2385 cfg80211_inform_bss_data+0x22b/0x3be0 net/wireless/scan.c:3240 cfg80211_inform_bss_frame_data+0x26f/0x750 net/wireless/scan.c:3331 ieee80211_bss_info_update+0x310/0xab0 net/mac80211/scan.c:226 ieee80211_scan_rx+0x4cf/0xb30 net/mac80211/scan.c:355 __ieee80211_rx_handle_packet net/mac80211/rx.c:5194 [inline] ieee80211_rx_list+0x1b9b/0x2ab0 net/mac80211/rx.c:5447 ieee80211_rx_napi+0xdc/0x410 net/mac80211/rx.c:5470 ieee80211_rx include/net/mac80211.h:5214 [inline] ieee80211_handle_queued_frames+0xd5/0x130 net/mac80211/main.c:453 tasklet_action_common+0x284/0x400 kernel/softirq.c:925 handle_softirqs+0x219/0x8e0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:clear_page_erms+0xb/0x20 arch/x86/lib/clear_page_64.S:52 Code: 48 8d 7f 40 75 d9 90 e9 d3 4b 04 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa b9 00 10 00 00 31 c0 aa c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 90 RSP: 0018:ffffc9002a787470 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88808942d000 RCX: 00000000000007c0 RDX: fffffbfff1bb40aa RSI: fffffbfff1bb40a8 RDI: ffff88808942d840 RBP: ffffea0002250a00 R08: 0000000000001000 R09: 0000000000000000 R10: ffffed1011285000 R11: dffffc0000000000 R12: 00000000000d2820 R13: ffffea0002250c00 R14: 0000000000000003 R15: ffffea0002250b40 clear_page arch/x86/include/asm/page_64.h:54 [inline] clear_highpage_kasan_tagged include/linux/highmem.h:248 [inline] kernel_init_pages mm/page_alloc.c:1227 [inline] post_alloc_hook+0x135/0x230 mm/page_alloc.c:1848 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x10a3/0x3a30 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x25f/0x2470 mm/page_alloc.c:5183 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3046 [inline] allocate_slab mm/slub.c:3219 [inline] new_slab+0x24a/0x360 mm/slub.c:3273 ___slab_alloc+0xdc4/0x1ae0 mm/slub.c:4643 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4762 __slab_alloc_node mm/slub.c:4838 [inline] slab_alloc_node mm/slub.c:5260 [inline] __do_kmalloc_node mm/slub.c:5633 [inline] __kmalloc_node_track_caller_noprof+0x4db/0x8a0 mm/slub.c:5743 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:601 __alloc_skb+0x166/0x380 net/core/skbuff.c:670 alloc_skb include/linux/skbuff.h:1383 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:763 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] nsim_dev_trap_report_work+0x2b1/0xcf0 drivers/net/netdevsim/dev.c:866 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245