INFO: task syz-executor341:5064 blocked for more than 143 seconds. Not tainted 6.6.0-rc3-syzkaller-00055-g9ed22ae6be81 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor341 state:D stack:23720 pid:5064 ppid:5062 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x196c/0x4af0 kernel/sched/core.c:6695 schedule+0xc3/0x180 kernel/sched/core.c:6771 schedule_timeout+0xb0/0x300 kernel/time/timer.c:2143 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x354/0x620 kernel/sched/completion.c:148 __flush_work+0x950/0xac0 kernel/workqueue.c:3407 nilfs_segctor_destroy fs/nilfs2/segment.c:2766 [inline] nilfs_detach_log_writer+0x47d/0xbe0 fs/nilfs2/segment.c:2850 nilfs_put_super+0x4d/0x160 fs/nilfs2/super.c:499 generic_shutdown_super+0x13a/0x2c0 fs/super.c:693 kill_block_super+0x41/0x70 fs/super.c:1646 deactivate_locked_super+0xa4/0x110 fs/super.c:481 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1254 task_work_run+0x24a/0x300 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:171 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:296 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f82c16c2487 RSP: 002b:00007ffc98a2d238 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f82c16c2487 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffc98a2d2f0 RBP: 00007ffc98a2d2f0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000202 R12: 00007ffc98a2e360 R13: 0000555556e7d6c0 R14: 431bde82d7b634db R15: 00007ffc98a2e380 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d32c420 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:303 [inline] #0: ffffffff8d32c420 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:749 [inline] #0: ffffffff8d32c420 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6613 3 locks held by kworker/0:2/779: #0: ffff888012870d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #0: ffff888012870d38 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1400 kernel/workqueue.c:2703 #1: ffffc9000407fd20 ((work_completion)(&sci->sc_iput_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #1: ffffc9000407fd20 ((work_completion)(&sci->sc_iput_work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1400 kernel/workqueue.c:2703 #2: ffff88807e5f4600 (sb_internal#2){.+.+}-{0:0}, at: nilfs_evict_inode+0x167/0x500 fs/nilfs2/inode.c:929 2 locks held by getty/4781: #0: ffff88814afb50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b1/0x1dc0 drivers/tty/n_tty.c:2206 1 lock held by syz-executor341/5064: #0: ffff88807e5f40e0 (&type->s_umount_key#46){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807e5f40e0 (&type->s_umount_key#46){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807e5f40e0 (&type->s_umount_key#46){+.+.}-{3:3}, at: deactivate_super+0xad/0xf0 fs/super.c:513 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.6.0-rc3-syzkaller-00055-g9ed22ae6be81 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x498/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x310 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfa9/0xff0 kernel/hung_task.c:379 kthread+0x2d3/0x370 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4473 Comm: klogd Not tainted 6.6.0-rc3-syzkaller-00055-g9ed22ae6be81 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 RIP: 0010:find_stack lib/stackdepot.c:351 [inline] RIP: 0010:__stack_depot_save+0x15a/0x650 lib/stackdepot.c:390 Code: 48 8b 2d b1 b5 a8 0d 8b 1d a7 b5 a8 0d 44 21 f3 4c 8b 64 dd 00 45 89 c5 eb 04 4d 8b 24 24 4d 85 e4 74 2c 45 39 74 24 08 75 f0 <45> 39 44 24 0c 75 e9 31 c0 49 8b 0c c7 49 3b 4c c4 18 75 dc 48 ff RSP: 0018:ffffc9000e7c7458 EFLAGS: 00000246 RAX: 00000000d39f01f5 RBX: 00000000000e7676 RCX: 00000000a37e82e7 RDX: ffffc9000e7c7504 RSI: 0000000000000001 RDI: 0000000000400cc0 RBP: ffff88823b400000 R08: 000000000000000c R09: 1ffffffff1d34f1d R10: dffffc0000000000 R11: fffffbfff1d34f1e R12: ffff88807ec63b50 R13: 000000000000000c R14: 0000000082de7676 R15: ffffc9000e7c74b0 FS: 00007facd2320380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055ee4e721630 CR3: 000000007e1b1000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x61/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x66/0x70 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x67/0x3d0 mm/slab.h:762 slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x148/0x330 mm/slub.c:3523 __alloc_skb+0x181/0x420 net/core/skbuff.c:640 alloc_skb include/linux/skbuff.h:1286 [inline] alloc_skb_with_frags+0xc3/0x780 net/core/skbuff.c:6313 sock_alloc_send_pskb+0x919/0xa50 net/core/sock.c:2795 unix_dgram_sendmsg+0x659/0x2070 net/unix/af_unix.c:1953 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg net/socket.c:753 [inline] __sys_sendto+0x484/0x640 net/socket.c:2177 __do_sys_sendto net/socket.c:2189 [inline] __se_sys_sendto net/socket.c:2185 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2185 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7facd24829b5 Code: 8b 44 24 08 48 83 c4 28 48 98 c3 48 98 c3 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 26 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 7a 48 8b 15 44 c4 0c 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffe2b17acd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007facd24829b5 RDX: 000000000000008b RSI: 0000562554dcad80 RDI: 0000000000000003 RBP: 0000562554dc6910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000013 R13: 00007facd2610212 R14: 00007ffe2b17add8 R15: 0000000000000000 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.683 msecs