INFO: task syz-executor.4:3547 blocked for more than 143 seconds. Not tainted 5.15.123-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:19800 pid: 3547 ppid: 3531 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5026 [inline] __schedule+0x12c4/0x4590 kernel/sched/core.c:6372 schedule+0x11b/0x1f0 kernel/sched/core.c:6455 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 sync_inodes_sb+0x293/0xab0 fs/fs-writeback.c:2748 sync_filesystem+0x16b/0x220 fs/sync.c:64 generic_shutdown_super+0x6e/0x2c0 fs/super.c:448 kill_block_super+0x7a/0xe0 fs/super.c:1405 deactivate_locked_super+0xa0/0x110 fs/super.c:335 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143 task_work_run+0x129/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:175 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x5d/0x250 kernel/entry/common.c:301 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7fef9abc2e17 RSP: 002b:00007ffe0423f378 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fef9abc2e17 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffe0423f430 RBP: 00007ffe0423f430 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe042404f0 R13: 00007fef9ac0c3b9 R14: 0000000000053c4e R15: 000000000000000a INFO: task syz-executor.1:3550 blocked for more than 143 seconds. Not tainted 5.15.123-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:20664 pid: 3550 ppid: 1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5026 [inline] __schedule+0x12c4/0x4590 kernel/sched/core.c:6372 schedule+0x11b/0x1f0 kernel/sched/core.c:6455 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 sync_inodes_sb+0x293/0xab0 fs/fs-writeback.c:2748 sync_filesystem+0x16b/0x220 fs/sync.c:64 generic_shutdown_super+0x6e/0x2c0 fs/super.c:448 kill_block_super+0x7a/0xe0 fs/super.c:1405 deactivate_locked_super+0xa0/0x110 fs/super.c:335 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143 task_work_run+0x129/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:175 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x5d/0x250 kernel/entry/common.c:301 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7ff97d2f3e17 RSP: 002b:00007ffca607d688 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007ff97d2f3e17 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffca607d740 RBP: 00007ffca607d740 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffca607e800 R13: 00007ff97d33d3b9 R14: 0000000000053568 R15: 000000000000000a Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c91e920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by kworker/u4:5/1230: #0: ffff888014de4938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000551fd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by getty/3262: #0: ffff888023f74098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002bb62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1da0 drivers/tty/n_tty.c:2147 2 locks held by syz-executor.4/3547: #0: ffff888093bfe0e0 (&type->s_umount_key#32){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365 #1: ffff88801b4de7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff88801b4de7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xab0 fs/fs-writeback.c:2746 2 locks held by syz-executor.1/3550: #0: ffff8880157b60e0 (&type->s_umount_key#32){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365 #1: ffff888147b6e7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff888147b6e7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xab0 fs/fs-writeback.c:2746 5 locks held by kworker/u4:7/4829: #0: ffff888014de4938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000509fd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffff8880b9a396d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 #3: ffff8880b9a27848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x53d/0x810 kernel/sched/psi.c:891 #4: ffffffff91664908 (&obj_hash[i].lock){-.-.}-{2:2}, at: __debug_check_no_obj_freed lib/debugobjects.c:994 [inline] #4: ffffffff91664908 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_check_no_obj_freed+0xc2/0x610 lib/debugobjects.c:1037 3 locks held by kworker/u4:8/4954: #0: ffff8880b9a396d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 #1: ffff8880b9a27848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4e1/0x810 kernel/sched/psi.c:882 #2: ffff8880b9a396d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.123-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:295 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3654 Comm: kworker/u4:4 Not tainted 5.15.123-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023 Workqueue: phy8 ieee80211_iface_work RIP: 0010:__hlist_del include/linux/list.h:858 [inline] RIP: 0010:hlist_del include/linux/list.h:870 [inline] RIP: 0010:__alloc_object lib/debugobjects.c:216 [inline] RIP: 0010:alloc_object+0x128/0x6c0 lib/debugobjects.c:229 Code: 08 4c 89 f7 e8 99 3d be fd 49 89 2e 48 85 ed 74 27 48 83 c5 08 48 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 48 89 ef e8 6e 3d be fd 4c 89 75 00 49 be 00 00 00 00 00 fc RSP: 0018:ffffc900047ff1b0 EFLAGS: 00000046 RAX: 1ffff1100cac6416 RBX: ffff888096b66150 RCX: dffffc0000000000 RDX: ffffffff8a8c0640 RSI: ffffffff8ad86b60 RDI: ffffffff8ad86b20 RBP: ffff8880656320b0 R08: dffffc0000000000 R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 1ffff11012d6cc2a R13: ffff888096b66158 R14: ffff8880b9a36390 R15: 1ffff11012d6cc2b FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056395664f600 CR3: 0000000023241000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lookup_object_or_alloc lib/debugobjects.c:581 [inline] debug_object_activate+0x23b/0x860 lib/debugobjects.c:695 debug_rcu_head_queue kernel/rcu/rcu.h:176 [inline] kvfree_call_rcu+0xb6/0x8a0 kernel/rcu/tree.c:3574 cfg80211_update_known_bss+0x16b/0x9e0 cfg80211_bss_update+0x16d/0x20d0 net/wireless/scan.c:1767 cfg80211_inform_single_bss_frame_data net/wireless/scan.c:2484 [inline] cfg80211_inform_bss_frame_data+0xa13/0x20f0 net/wireless/scan.c:2517 ieee80211_bss_info_update+0x7a6/0xc80 net/mac80211/scan.c:190 ieee80211_rx_bss_info net/mac80211/ibss.c:1123 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1614 [inline] ieee80211_ibss_rx_queued_mgmt+0x175e/0x2af0 net/mac80211/ibss.c:1643 ieee80211_iface_process_skb net/mac80211/iface.c:1441 [inline] ieee80211_iface_work+0x78f/0xcc0 net/mac80211/iface.c:1495 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298