INFO: task syz.3.138:9057 blocked for mor[ 850.860276][ T38] INFO: task syz.3.138:9057 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.138 state:D stack:22520 pid:9057 tgid:9056 ppid:8574 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 io_schedule+0x81/0xe0 kernel/sched/core.c:7903 TXN_SLEEP_DROP_LOCK fs/jfs/jfs_txnmgr.c:125 [inline] txBegin+0x26e/0xb10 fs/jfs/jfs_txnmgr.c:374 jfs_set_acl+0xf5/0x320 fs/jfs/acl.c:106 set_posix_acl fs/posix_acl.c:954 [inline] vfs_remove_acl+0x495/0x700 fs/posix_acl.c:1241 ovl_do_remove_acl fs/overlayfs/overlayfs.h:355 [inline] ovl_workdir_create+0x594/0x8b0 fs/overlayfs/super.c:354 ovl_make_workdir fs/overlayfs/super.c:669 [inline] ovl_get_workdir+0x32f/0x17c0 fs/overlayfs/super.c:827 ovl_fill_super+0x1365/0x35b0 fs/overlayfs/super.c:1406 vfs_get_super fs/super.c:1325 [inline] get_tree_nodev+0xbb/0x150 fs/super.c:1344 vfs_get_tree+0x92/0x2b0 fs/super.c:1815 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3808 do_mount fs/namespace.c:4136 [inline] __do_sys_mount fs/namespace.c:4347 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4324 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6decc2eec9 RSP: 002b:00007f6deae96038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f6dece85fa0 RCX: 00007f6decc2eec9 RDX: 0000200000000b80 RSI: 0000200000000000 RDI: 0000000000000000 RBP: 00007f6deccb1f91 R08: 0000200000000180 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6dece86038 R14: 00007f6dece85fa0 R15: 00007ffd01a68bc8 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 8 locks held by kworker/u8:2/43: 7 locks held by kworker/u8:4/71: #0: ffff888061ddd938 ((wq_completion)btrfs-endio-write){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888061ddd938 ((wq_completion)btrfs-endio-write){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000152fbc0 ((work_completion)(&work->normal_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000152fbc0 ((work_completion)(&work->normal_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffff888066f8af98 (btrfs_ordered_extent){++++}-{0:0}, at: btrfs_finish_one_ordered+0x30e/0x1fd0 fs/btrfs/inode.c:3103 #3: ffff888021706778 (sb_internal#6){.+.+}-{0:0}, at: btrfs_finish_one_ordered+0x573/0x1fd0 fs/btrfs/inode.c:3140 #4: ffff888066f8ae80 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x41b/0xca0 fs/btrfs/transaction.c:296 #5: ffff888066f8aea8 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x41b/0xca0 fs/btrfs/transaction.c:296 #6: ffff888025b93a98 (btrfs-tree-01){++++}-{4:4}, at: btrfs_tree_lock_nested+0x31/0x230 fs/btrfs/locking.c:188 5 locks held by kworker/u8:6/154: #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90003ad7bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90003ad7bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecc6a20 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658 #3: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: wg_netns_pre_exit+0x1c/0x1d0 drivers/net/wireguard/device.c:417 #4: ffff88804a2117b8 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_netns_pre_exit+0xb0/0x1d0 drivers/net/wireguard/device.c:422 3 locks held by kworker/u8:7/1018: #0: ffff88814cf81938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88814cf81938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90004d2fbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90004d2fbc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194 3 locks held by kworker/u8:11/1461: #0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90005b4fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90005b4fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 2 locks held by getty/5597: #0: ffff88823bf288a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222 2 locks held by kworker/1:6/5931: #0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90004fcfbc0 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90004fcfbc0 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 2 locks held by kworker/u8:1/8548: 3 locks held by syz.3.138/9057: #0: ffff888038d380d0 (&type->s_umount_key#50/1){+.+.}-{4:4}, at: alloc_super+0x204/0x990 fs/super.c:345 #1: ffff888036dc6488 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #2: ffff88803e380f88 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: inode_lock include/linux/fs.h:870 [inline] #2: ffff88803e380f88 (&type->i_mutex_dir_key#14){++++}-{4:4}, at: vfs_remove_acl+0xf9/0x700 fs/posix_acl.c:1222 2 locks held by syz-executor/10446: #0: ffffffff8e43b9e0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e43b9e0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e43b9e0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056 1 lock held by syz-executor/10513: #0: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056 1 lock held by syz-executor/10569: #0: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056 3 locks held by syz.2.348/10647: #0: ffff88807163ebc8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x19f/0x3d0 mm/mmap_lock.c:147 #1: ffff888021706600 (sb_pagefaults#2){.+.+}-{0:0}, at: do_page_mkwrite+0x150/0x310 mm/memory.c:3361 #2: ffff88805f9c04a8 (&ei->i_mmap_lock){++++}-{4:4}, at: btrfs_page_mkwrite+0x608/0x1a80 fs/btrfs/file.c:1920 8 locks held by syz.2.348/10648: 1 lock held by udevadm/10680: 2 locks held by sed/10682: 1 lock held by syz-executor/10683: #0: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:978 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:148 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: 10680 Comm: udevadm Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:do_dentry_open+0xaf5/0x1350 fs/open.c:973 Code: 8b 34 24 45 89 2e 48 8b 44 24 08 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 0f 85 bf 06 00 00 45 8b 2e 44 89 ee 83 e6 02 <31> ff e8 a4 74 95 ff 44 89 e8 83 e0 02 75 0e e8 e7 6f 95 ff 4c 8b RSP: 0018:ffffc90004107848 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff88803ca6f800 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88803ca6f888 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff81fe2570 R12: 1ffff1100794df11 R13: 00000000044a801d R14: ffff88803ca6f880 R15: ffffffff8b14fcd8 FS: 00007f3246974880(0000) GS:ffff8881268bc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb5b2d7f724 CR3: 000000003c9e6000 CR4: 00000000003526f0 Call Trace: vfs_open+0x3b/0x350 fs/open.c:1095 do_open fs/namei.c:3887 [inline] path_openat+0x2ef1/0x3840 fs/namei.c:4046 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1461 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3246a62407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007fff1c233ce0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f3246974880 RCX: 00007f3246a62407 RDX: 0000000000080000 RSI: 00007fff1c233e50 RDI: ffffffffffffff9c RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000055634b4e8ee0 R13: 000055634b4e8ee0 R14: 0000000000000001 R15: 000055636c2cde60