INFO: task syz-executor.2:5054 blocked for more than 143 seconds. Not tainted 6.4.0-rc4-syzkaller-00051-g48b1320a674e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:21120 pid:5054 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5343 [inline] __schedule+0x187b/0x4900 kernel/sched/core.c:6669 schedule+0xc3/0x180 kernel/sched/core.c:6745 wb_wait_for_completion+0x166/0x290 fs/fs-writeback.c:192 sync_inodes_sb+0x297/0xab0 fs/fs-writeback.c:2730 sync_filesystem+0x16f/0x220 fs/sync.c:64 generic_shutdown_super+0x6f/0x340 fs/super.c:473 kill_block_super+0x84/0xf0 fs/super.c:1407 deactivate_locked_super+0xa4/0x110 fs/super.c:331 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1177 task_work_run+0x24a/0x300 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xd9/0x100 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:286 [inline] syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:297 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fcbb388d5d7 RSP: 002b:00007fffb10103e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fcbb388d5d7 RDX: 00007fffb10104bb RSI: 000000000000000a RDI: 00007fffb10104b0 RBP: 00007fffb10104b0 R08: 00000000ffffffff R09: 00007fffb1010280 R10: 0000555556bbf893 R11: 0000000000000246 R12: 00007fcbb38e6cdc R13: 00007fffb1011570 R14: 0000555556bbf810 R15: 00007fffb10115b0 Showing all locks held in the system: 2 locks held by kworker/u4:1/12: #0: ffff888012ef4138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x77e/0x10e0 kernel/workqueue.c:2378 #1: ffffc90000117d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7c8/0x10e0 kernel/workqueue.c:2380 1 lock held by rcu_tasks_kthre/13: #0: ffffffff8cf276f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:518 1 lock held by rcu_tasks_trace/14: #0: ffffffff8cf27ab0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:518 1 lock held by khungtaskd/28: #0: ffffffff8cf27520 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/4753: #0: ffff88802cb1a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900015b02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ab/0x1db0 drivers/tty/n_tty.c:2176 2 locks held by syz-executor.2/5054: #0: ffff8880347f20e0 (&type->s_umount_key#73){++++}-{3:3}, at: deactivate_super+0xad/0xf0 fs/super.c:361 #1: ffff88801eee47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:364 [inline] #1: ffff88801eee47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x278/0xab0 fs/fs-writeback.c:2728 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.4.0-rc4-syzkaller-00051-g48b1320a674e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 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+0x187/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xec2/0xf00 kernel/hung_task.c:379 kthread+0x2b8/0x350 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 46 Comm: kworker/u4:3 Not tainted 6.4.0-rc4-syzkaller-00051-g48b1320a674e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 Workqueue: phy14 ieee80211_iface_work RIP: 0010:__stack_depot_save+0x145/0x650 lib/stackdepot.c:390 Code: c0 0e 29 c5 41 31 ee c1 c5 18 41 29 ee eb 06 44 89 ee 44 89 e7 48 8b 2d b1 40 7c 0d 8b 1d a7 40 7c 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 RSP: 0018:ffffc90000007828 EFLAGS: 00000202 RAX: 000000000148b78f RBX: 00000000000810f7 RCX: 00000000a86126c2 RDX: ffffc900000078e0 RSI: 0000000000000001 RDI: 0000000000000800 RBP: ffff88823b400000 R08: 000000000000000d R09: ffffc900000077f0 R10: ffffc90000007750 R11: dffffc0000000001 R12: ffff88807a60f500 R13: 0000000000000001 R14: 000000008e1810f7 R15: ffffc90000007880 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555740032270 CR3: 0000000027afa000 CR4: 00000000003506f0 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_save_free_info+0x2b/0x40 mm/kasan/generic.c:521 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook mm/slub.c:1807 [inline] slab_free mm/slub.c:3786 [inline] kmem_cache_free+0x297/0x520 mm/slub.c:3808 skb_kfree_head net/core/skbuff.c:903 [inline] skb_free_head net/core/skbuff.c:918 [inline] skb_release_data+0x637/0x850 net/core/skbuff.c:948 skb_release_all net/core/skbuff.c:1014 [inline] __kfree_skb net/core/skbuff.c:1028 [inline] consume_skb+0xb3/0x150 net/core/skbuff.c:1244 mac80211_hwsim_beacon_tx+0x3a5/0x750 drivers/net/wireless/virtual/mac80211_hwsim.c:2257 __iterate_interfaces+0x21e/0x4b0 net/mac80211/util.c:766 ieee80211_iterate_active_interfaces_atomic+0xb3/0x140 net/mac80211/util.c:802 mac80211_hwsim_beacon+0xd4/0x1e0 drivers/net/wireless/virtual/mac80211_hwsim.c:2283 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x59f/0xd10 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x19a/0x2c0 kernel/time/hrtimer.c:1766 __do_softirq+0x2ab/0x908 kernel/softirq.c:571 do_softirq+0x166/0x250 kernel/softirq.c:472 __local_bh_enable_ip+0x1b5/0x1f0 kernel/softirq.c:396 spin_unlock_bh include/linux/spinlock.h:395 [inline] cfg80211_bss_update+0x1170/0x20d0 net/wireless/scan.c:1808 cfg80211_inform_single_bss_frame_data net/wireless/scan.c:2482 [inline] cfg80211_inform_bss_frame_data+0xc5b/0x22c0 net/wireless/scan.c:2515 ieee80211_bss_info_update+0x801/0xf00 net/mac80211/scan.c:190 ieee80211_rx_bss_info net/mac80211/ibss.c:1120 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1609 [inline] ieee80211_ibss_rx_queued_mgmt+0x192f/0x2cf0 net/mac80211/ibss.c:1638 ieee80211_iface_process_skb net/mac80211/iface.c:1594 [inline] ieee80211_iface_work+0x7bd/0xd00 net/mac80211/iface.c:1648 process_one_work+0x8a0/0x10e0 kernel/workqueue.c:2405 worker_thread+0xa63/0x1210 kernel/workqueue.c:2552 kthread+0x2b8/0x350 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308