INFO: task syz-executor.4:5096 blocked for more than 143 seconds. Not tainted 6.7.0-rc4-syzkaller-00358-gf2e8a57ee903 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:18896 pid:5096 tgid:5096 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5376 [inline] __schedule+0x1961/0x4ab0 kernel/sched/core.c:6688 __schedule_loop kernel/sched/core.c:6763 [inline] schedule+0x149/0x260 kernel/sched/core.c:6778 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6835 rwsem_down_write_slowpath+0xeea/0x13b0 kernel/locking/rwsem.c:1178 __down_write_common+0x1aa/0x200 kernel/locking/rwsem.c:1306 __super_lock fs/super.c:56 [inline] __super_lock_excl fs/super.c:71 [inline] deactivate_super+0xad/0xf0 fs/super.c:516 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1256 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+0xb1/0x150 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x69/0x2a0 kernel/entry/common.c:296 do_syscall_64+0x52/0x110 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7fb79107ded7 RSP: 002b:00007ffcd1cda298 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fb79107ded7 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffcd1cda350 RBP: 00007ffcd1cda350 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffcd1cdb410 R13: 00007fb7910c73b9 R14: 000000000005b9da R15: 000000000000000a Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d92d060 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff8d92d060 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff8d92d060 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 4 locks held by kworker/u4:5/749: 2 locks held by getty/4813: #0: ffff8880267a10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 1 lock held by syz-executor.4/5096: #0: ffff88801c5080e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88801c5080e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88801c5080e0 (&type->s_umount_key#76){++++}-{3:3}, at: deactivate_super+0xad/0xf0 fs/super.c:516 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.7.0-rc4-syzkaller-00358-gf2e8a57ee903 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 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+0xfaf/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:242 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 2803 Comm: kworker/u4:8 Not tainted 6.7.0-rc4-syzkaller-00358-gf2e8a57ee903 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:check_kcov_mode kernel/kcov.c:175 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x30/0x60 kernel/kcov.c:207 Code: 04 24 65 48 8b 0d 00 3c 75 7e 65 8b 15 01 3c 75 7e f7 c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 fc 15 00 00 00 74 2c <8b> 91 d8 15 00 00 83 fa 02 75 21 48 8b 91 e0 15 00 00 48 8b 32 48 RSP: 0018:ffffc9000a717690 EFLAGS: 00000246 RAX: ffffffff813dacf1 RBX: ffffc9000a717708 RCX: ffff888026ec1dc0 RDX: 0000000080000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffffff813dace8 R09: ffffffff813dc790 R10: 0000000000000003 R11: ffff888026ec1dc0 R12: ffff888026ec1dc0 R13: ffffffff817bebf0 R14: dffffc0000000000 R15: 1ffff920014e2ee1 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055dd71023600 CR3: 000000000d730000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_get_return_address+0x71/0xc0 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0x11f/0x1a0 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x117/0x1c0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook mm/slub.c:1826 [inline] slab_free mm/slub.c:3809 [inline] kmem_cache_free+0x299/0x470 mm/slub.c:3831 kfree_skb include/linux/skbuff.h:1234 [inline] ieee80211_iface_work+0x26c/0xd90 net/mac80211/iface.c:1645 cfg80211_wiphy_work+0x21e/0x250 net/wireless/core.c:437 process_one_work kernel/workqueue.c:2627 [inline] process_scheduled_works+0x90f/0x1420 kernel/workqueue.c:2700 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2781 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:242