INFO: task syz.8.709:13621 blocked for more than 143 seconds. Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.709 state:D stack:24520 pid:13621 tgid:13613 ppid:12300 task_flags:0x400140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b33/0x51f0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_read_slowpath kernel/locking/rwsem.c:1084 [inline] __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x6ff/0xa50 kernel/locking/rwsem.c:1526 __super_lock fs/super.c:58 [inline] super_lock+0x27c/0x400 fs/super.c:120 user_get_super+0xd2/0x180 fs/super.c:1000 quotactl_block fs/quota/quota.c:890 [inline] __do_sys_quotactl fs/quota/quota.c:955 [inline] __se_sys_quotactl+0x527/0xa40 fs/quota/quota.c:917 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc6c438e169 RSP: 002b:00007fc6c52c7038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 00007fc6c45b5fa0 RCX: 00007fc6c438e169 RDX: 0000000000000000 RSI: 0000200000000040 RDI: ffffffff80000800 RBP: 00007fc6c4410a68 R08: 0000000000000000 R09: 0000000000000000 R10: 0000200000000100 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc6c45b5fa0 R15: 00007fffa8d87c38 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 4 locks held by kworker/u8:2/36: 3 locks held by kworker/u8:3/53: #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+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000be7c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000be7c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 4 locks held by udevd/5202: #0: ffff88802908fb08 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb4/0xda0 fs/seq_file.c:182 #1: ffff88807ee68888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154 #2: ffff888049bc84b8 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x72/0x3b0 fs/kernfs/file.c:155 #3: ffff888059c070e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #3: ffff888059c070e8 (&dev->mutex){....}-{4:4}, at: uevent_show+0x17d/0x340 drivers/base/core.c:2730 2 locks held by dhcpcd/5495: #0: ffffffff900cfd08 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x6d1/0x900 net/socket.c:1273 #1: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0x118/0xa20 net/8021q/vlan.c:554 2 locks held by getty/5586: #0: ffff88803190b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 4 locks held by kworker/u8:9/6525: 2 locks held by syz-executor/9454: 2 locks held by syz-executor/9646: 3 locks held by syz-executor/10699: 2 locks held by syz-executor/13367: 1 lock held by syz.8.709/13621: #0: ffff888030cf00e0 (&type->s_umount_key#79){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888030cf00e0 (&type->s_umount_key#79){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz.2.799/14566: #0: ffff88803ea7a0e0 (&type->s_umount_key#79){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88803ea7a0e0 (&type->s_umount_key#79){++++}-{4:4}, at: super_lock+0x19b/0x400 fs/super.c:120 7 locks held by syz-executor/15763: #0: ffff8880360e4420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #0: ffff8880360e4420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 #1: ffff888037cab088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e2/0x510 fs/kernfs/file.c:325 #2: ffff8881443d0c38 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x206/0x510 fs/kernfs/file.c:326 #3: ffffffff8f984c28 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x1b6/0x8c0 drivers/net/netdevsim/bus.c:166 #4: ffff888059c070e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #4: ffff888059c070e8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x90/0x530 drivers/base/dd.c:1005 #5: ffff8880883f9250 (&devlink->lock_key#30){+.+.}-{4:4}, at: nsim_drv_probe+0xc9/0xbc0 drivers/net/netdevsim/dev.c:1537 #6: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:948 [inline] #6: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: nsim_create+0x7f4/0xf00 drivers/net/netdevsim/netdev.c:1028 1 lock held by syz-executor/15932: #0: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xd68/0x1fe0 net/core/rtnetlink.c:4064 2 locks held by syz-executor/16040: #0: ffffffff900de750 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:514 #1: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x87/0x270 net/ipv4/nexthop.c:3918 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0 PREEMPT(full) 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+0x4ab/0x4e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:437 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 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: 4315 Comm: kworker/u8:8 Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_acquire+0x2a4/0xd80 kernel/locking/lockdep.c:5173 Code: 54 cd 18 65 8b 15 88 dc c6 11 31 f6 85 d2 40 0f 95 c6 31 d2 83 bd d4 0a 00 00 00 0f 95 c2 8d 34 72 c1 e6 0d 09 c6 8b 54 24 28 e2 0f 0f b7 d2 09 f2 41 83 e4 03 41 c1 e4 10 44 89 c6 83 e6 01 RSP: 0018:ffffc9000d227928 EFLAGS: 00000002 RAX: 0000000000000007 RBX: 0000000000000000 RCX: 000000000000000a RDX: 0000000000000000 RSI: 0000000000000007 RDI: 0000000000000002 RBP: ffff8880338c9e00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002 R13: ffff8880338ca8f0 R14: 0000000000000000 R15: ffffffff8ed3df20 FS: 0000000000000000(0000) GS:ffff8881250cf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5a51c7e8eb CR3: 000000000eb38000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] batadv_nc_process_nc_paths+0xd6/0x3a0 net/batman-adv/network-coding.c:687 batadv_nc_worker+0x42a/0x610 net/batman-adv/network-coding.c:728 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245