INFO: task syz.7.1981:15911 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.1981 state:D stack:28064 pid:15911 tgid:15910 ppid:13675 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340 rwsem_down_read_slowpath+0x6d9/0x940 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1570 __super_lock fs/super.c:60 [inline] super_lock+0x2d6/0x3d0 fs/super.c:122 __iterate_supers+0x126/0x250 fs/super.c:926 ksys_sync fs/sync.c:102 [inline] __ia32_sys_sync+0xa0/0x120 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7bebb9ce59 RSP: 002b:00007f7be9df6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f7bebe15fa0 RCX: 00007f7bebb9ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f7bebe15fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7bebe16038 R14: 00007f7bebe15fa0 R15: 00007ffe25910688 INFO: task syz.1.2020:16066 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.2020 state:D stack:27224 pid:16066 tgid:16062 ppid:9518 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340 rwsem_down_read_slowpath+0x6d9/0x940 kernel/locking/rwsem.c:1114 __down_read_common kernel/locking/rwsem.c:1291 [inline] __down_read kernel/locking/rwsem.c:1304 [inline] down_read+0x99/0x2e0 kernel/locking/rwsem.c:1570 __super_lock fs/super.c:60 [inline] super_lock+0x2d6/0x3d0 fs/super.c:122 __iterate_supers+0x126/0x250 fs/super.c:926 ksys_sync fs/sync.c:102 [inline] __ia32_sys_sync+0xa0/0x120 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0b7079ce59 RSP: 002b:00007f0b7162d028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f0b70a15fa0 RCX: 00007f0b7079ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f0b70a15fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0b70a16038 R14: 00007f0b70a15fa0 R15: 00007ffe6b33a028 Showing all locks held in the system: 5 locks held by kworker/0:1/10: 3 locks held by kworker/u8:1/13: #0: ffff888031238140 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #0: ffff888031238140 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397 #1: ffffc90000127c40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline] #1: ffffc90000127c40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397 #2: ffffffff8fdc8ec0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8fdc8ec0 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4746 1 lock held by khungtaskd/31: #0: ffffffff8e95cd20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e95cd20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e95cd20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 5 locks held by kworker/u8:3/48: 2 locks held by kworker/u8:6/810: #0: ffff88801d3be940 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #0: ffff88801d3be940 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397 #1: ffffc90004aefc40 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline] #1: ffffc90004aefc40 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397 2 locks held by getty/5384: #0: ffff888035be90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5634: 3 locks held by kworker/0:5/14114: #0: ffff88813fe43140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #0: ffff88813fe43140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397 #1: ffffc9000395fc40 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline] #1: ffffc9000395fc40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397 #2: ffffffff8fdc8ec0 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 2 locks held by dhcpcd/15576: #0: ffff8880342c9940 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #0: ffff8880342c9940 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release net/socket.c:721 [inline] #0: ffff8880342c9940 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1514 #1: ffffffff8e963028 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8e963028 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 1 lock held by syz.7.1981/15911: #0: ffff8880537520d8 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff8880537520d8 (&type->s_umount_key#51){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz.1.2020/16066: #0: ffff8880537520d8 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff8880537520d8 (&type->s_umount_key#51){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz.6.2466/18001: #0: ffff8880537520d8 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff8880537520d8 (&type->s_umount_key#51){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz.9.2454/18056: #0: ffff88807b6c0cd0 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x3b/0x100 net/netfilter/nf_tables_api.c:11490 2 locks held by syz.9.2454/18057: #0: ffffffff9a93c380 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:96 [inline] #0: ffffffff9a93c380 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnetlink_rcv_batch net/netfilter/nfnetlink.c:392 [inline] #0: ffffffff9a93c380 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:647 [inline] #0: ffffffff9a93c380 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnetlink_rcv+0x634/0x27b0 net/netfilter/nfnetlink.c:665 #1: ffff88807b6c0cd0 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x3b/0x100 net/netfilter/nf_tables_api.c:11490 3 locks held by syz.9.2454/18059: #0: ffffffff90322ae0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff90322ae0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff90322ae0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8fdc8ec0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8fdc8ec0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8fdc8ec0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4109 #2: ffff88807b6c0cd0 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_netdev_event+0xad/0x160 net/netfilter/nft_chain_filter.c:416 2 locks held by cmp/18079: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 18069 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:assert_clock_updated kernel/sched/sched.h:1769 [inline] RIP: 0010:rq_clock kernel/sched/sched.h:1775 [inline] RIP: 0010:sched_info_arrive kernel/sched/stats.h:277 [inline] RIP: 0010:sched_info_switch kernel/sched/stats.h:339 [inline] RIP: 0010:prepare_task_switch kernel/sched/core.c:5175 [inline] RIP: 0010:context_switch kernel/sched/core.c:5333 [inline] RIP: 0010:__schedule+0xf04/0x5740 kernel/sched/core.c:7189 Code: 4c 89 e7 e8 3e b3 88 f6 49 8b 3c 24 48 83 c7 60 be ff ff ff ff e8 bc 1a ff ff 85 c0 0f 84 cb 0e 00 00 48 8b 84 24 c8 00 00 00 <42> 0f b6 04 30 84 c0 0f 85 e1 13 00 00 48 8b 44 24 60 83 38 01 0f RSP: 0018:ffffc9000d317420 EFLAGS: 00000002 RAX: 1ffff110170e7784 RBX: 1ffff110069d60ab RCX: 0000000080000002 RDX: ffff8880b873bf08 RSI: ffffffff8e217295 RDI: ffffffff8c28b9e0 RBP: ffffc9000d317640 R08: ffffffff903036f7 R09: 1ffffffff20606de R10: dffffc0000000000 R11: fffffbfff20606df R12: ffff8880b873bf08 R13: ffff888035b30558 R14: dffffc0000000000 R15: ffff888034eb0558 FS: 00007fef5d7c5c80(0000) GS:ffff8881253a0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056314a1e2048 CR3: 000000005a627000 CR4: 0000000000350ef0 Call Trace: preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7370 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 flush_tlb_mm_range+0xdd5/0x10b0 arch/x86/mm/tlb.c:1461 dup_mmap+0x17b0/0x1da0 mm/mmap.c:1905 dup_mm kernel/fork.c:1534 [inline] copy_mm+0x13b/0x4a0 kernel/fork.c:1586 copy_process+0x1f1c/0x4440 kernel/fork.c:2264 kernel_clone+0x2d7/0x940 kernel/fork.c:2722 __do_sys_clone kernel/fork.c:2863 [inline] __se_sys_clone kernel/fork.c:2847 [inline] __x64_sys_clone+0x1b6/0x230 kernel/fork.c:2847 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fef5d95f636 Code: 89 df e8 6d e8 f6 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 52 89 c5 85 c0 75 31 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffd52cd0130 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007ffd52cd0138 RCX: 00007fef5d95f636 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 000056314a1d1e60 R08: 0000000000000000 R09: 000056314a1d1c30 R10: 00007fef5d7c5f50 R11: 0000000000000246 R12: 000056314a1d5b40 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000