INFO: task syz.2.60:6442 blocked for more than 143 seconds. Not tainted 6.13.0-rc1-syzkaller-00005-gceb8bf2ceaa7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.60 state:D stack:25952 pid:6442 tgid:6436 ppid:5825 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905 rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694 inode_lock_nested include/linux/fs.h:853 [inline] do_rmdir+0x263/0x580 fs/namei.c:4441 __do_sys_rmdir fs/namei.c:4472 [inline] __se_sys_rmdir fs/namei.c:4470 [inline] __x64_sys_rmdir+0x47/0x50 fs/namei.c:4470 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5436d7ff19 RSP: 002b:00007f5437b4f058 EFLAGS: 00000246 ORIG_RAX: 0000000000000054 RAX: ffffffffffffffda RBX: 00007f5436f46160 RCX: 00007f5436d7ff19 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000140 RBP: 00007f5436df3986 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5436f46160 R15: 00007ffeff4232a8 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8e93cfb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #0: ffffffff8e93cfb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 3 locks held by kworker/u8:0/11: #0: ffff888030b44148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff888030b44148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc90000107d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000107d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fc9d0c8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4215 1 lock held by khungtaskd/31: #0: ffffffff8e937aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937aa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937aa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 3 locks held by kworker/u8:4/62: 3 locks held by kworker/u8:10/3568: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9000c6d7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000c6d7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fc9d0c8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 2 locks held by getty/5584: #0: ffff8880358020a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 1 lock held by syz.2.60/6441: 2 locks held by syz.2.60/6442: #0: ffff88805214e420 (sb_writers#28){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff888078618180 (&type->i_mutex_dir_key#16/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:853 [inline] #1: ffff888078618180 (&type->i_mutex_dir_key#16/1){+.+.}-{4:4}, at: do_rmdir+0x263/0x580 fs/namei.c:4441 2 locks held by syz-executor/7306: #0: ffff88802e9fc0e0 (&type->s_umount_key#30){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88802e9fc0e0 (&type->s_umount_key#30){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88802e9fc0e0 (&type->s_umount_key#30){++++}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8e9f8a88 (lock#3){+.+.}-{4:4}, at: __lru_add_drain_all+0x66/0x560 mm/swap.c:798 2 locks held by syz.6.178/7510: #0: ffffffff8fc9d0c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fc9d0c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 #1: ffffffff8e93cfb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #1: ffffffff8e93cfb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 1 lock held by syz-executor/7698: #0: ffffffff8fc9d0c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline] #0: ffffffff8fc9d0c8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x47e/0x1bd0 net/ipv4/devinet.c:987 1 lock held by rm/7902: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.13.0-rc1-syzkaller-00005-gceb8bf2ceaa7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xff6/0x1040 kernel/hung_task.c:397 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6441 Comm: syz.2.60 Not tainted 6.13.0-rc1-syzkaller-00005-gceb8bf2ceaa7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:check_preemption_disabled+0x4/0x120 lib/smp_processor_id.c:13 Code: 8c 48 c7 c6 80 90 5e 8c eb 1c 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 <41> 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 65 RSP: 0018:ffffc9000447ecc8 EFLAGS: 00000046 RAX: 1ffff1100551c15a RBX: 0000000000000246 RCX: ffffc9000447ed03 RDX: 0000000000000001 RSI: ffffffff8c0aa880 RDI: ffffffff8c5e90a0 RBP: ffffc9000447ee10 R08: ffffffff90181b77 R09: 1ffffffff203036e R10: dffffc0000000000 R11: fffffbfff203036f R12: 1ffff9200088fda8 R13: 0000000000000246 R14: ffffc9000447ed70 R15: dffffc0000000000 FS: 00007f5437b706c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005645153c99e0 CR3: 0000000024da2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:467 [inline] lock_release+0x5ec/0xa30 kernel/locking/lockdep.c:5872 rcu_lock_release include/linux/rcupdate.h:347 [inline] rcu_read_unlock include/linux/rcupdate.h:880 [inline] shrink_slab_memcg mm/shrinker.c:543 [inline] shrink_slab+0x856/0x14d0 mm/shrinker.c:628 shrink_node_memcgs mm/vmscan.c:5931 [inline] shrink_node+0x130f/0x2e10 mm/vmscan.c:5970 shrink_zones mm/vmscan.c:6215 [inline] do_try_to_free_pages+0x69d/0x1b20 mm/vmscan.c:6277 try_to_free_mem_cgroup_pages+0x4b8/0xaf0 mm/vmscan.c:6609 try_charge_memcg+0x8c7/0x1150 mm/memcontrol.c:2238 try_charge mm/memcontrol-v1.h:19 [inline] charge_memcg+0xa6/0x1e0 mm/memcontrol.c:4497 __mem_cgroup_charge+0x27/0x80 mm/memcontrol.c:4512 mem_cgroup_charge include/linux/memcontrol.h:646 [inline] filemap_add_folio+0xb3/0x650 mm/filemap.c:966 do_read_cache_folio+0x341/0x850 mm/filemap.c:3793 read_mapping_folio include/linux/pagemap.h:1011 [inline] dir_get_folio fs/sysv/dir.c:64 [inline] sysv_find_entry+0x16a/0x4b0 fs/sysv/dir.c:154 sysv_inode_by_name+0x98/0x2a0 fs/sysv/dir.c:370 sysv_lookup+0x6b/0xe0 fs/sysv/namei.c:38 __lookup_slow+0x28c/0x3f0 fs/namei.c:1791 lookup_slow+0x53/0x70 fs/namei.c:1808 walk_component+0x2e1/0x410 fs/namei.c:2112 lookup_last fs/namei.c:2610 [inline] path_lookupat+0x16f/0x450 fs/namei.c:2634 filename_lookup+0x2a3/0x670 fs/namei.c:2663 user_path_at+0x3a/0x60 fs/namei.c:3070 do_fchmodat fs/open.c:684 [inline] __do_sys_chmod fs/open.c:710 [inline] __se_sys_chmod fs/open.c:708 [inline] __x64_sys_chmod+0xd5/0x1a0 fs/open.c:708 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5436d7ff19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5437b70058 EFLAGS: 00000246 ORIG_RAX: 000000000000005a RAX: ffffffffffffffda RBX: 00007f5436f46080 RCX: 00007f5436d7ff19 RDX: 0000000000000000 RSI: 0000000000000140 RDI: 0000000020000180 RBP: 00007f5436df3986 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f5436f46080 R15: 00007ffeff4232a8