INFO: task kworker/u4:7:1060 blocked for more than 143 seconds. Not tainted 6.7.0-rc3-syzkaller-00033-g3b47bc037bd4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:7 state:D stack:21680 pid:1060 tgid:1060 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:2) 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 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6a3/0xd60 kernel/locking/mutex.c:747 exfat_write_inode+0x69/0x120 fs/exfat/inode.c:96 write_inode fs/fs-writeback.c:1473 [inline] __writeback_single_inode+0x69b/0xfc0 fs/fs-writeback.c:1690 writeback_sb_inodes+0x8e3/0x1220 fs/fs-writeback.c:1916 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:1987 wb_writeback+0x461/0xc70 fs/fs-writeback.c:2094 wb_check_background_flush fs/fs-writeback.c:2164 [inline] wb_do_writeback fs/fs-writeback.c:2252 [inline] wb_workfn+0xc33/0xfb0 fs/fs-writeback.c:2279 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0x90f/0x1420 kernel/workqueue.c:2703 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2784 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 Showing all locks held in the system: 4 locks held by kworker/u4:0/11: #0: ffff888015266138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #0: ffff888015266138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2703 #1: ffffc90000107d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #1: ffffc90000107d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2703 #2: ffff88807edf40e0 (&type->s_umount_key#54){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:610 #3: ffff88801efe00e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x69/0x120 fs/exfat/inode.c:96 4 locks held by kworker/u4:1/12: #0: ffff888015266138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #0: ffff888015266138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2703 #1: ffffc90000117d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #1: ffffc90000117d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2703 #2: ffff88806d9120e0 (&type->s_umount_key#54){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:610 #3: ffff88806fa5a0e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x69/0x120 fs/exfat/inode.c:96 1 lock held by khungtaskd/30: #0: ffffffff8d92cf60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff8d92cf60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff8d92cf60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 4 locks held by kworker/u4:4/741: #0: ffff888015266138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #0: ffff888015266138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2703 #1: ffffc900035bfd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #1: ffffc900035bfd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2703 #2: ffff88806f90c0e0 (&type->s_umount_key#54){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:610 #3: ffff8880266380e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x69/0x120 fs/exfat/inode.c:96 2 locks held by kworker/u4:5/1043: 4 locks held by kworker/u4:7/1060: #0: ffff888015266138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #0: ffff888015266138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2703 #1: ffffc90004417d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #1: ffffc90004417d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2703 #2: ffff8880193320e0 (&type->s_umount_key#54){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:610 #3: ffff888029b6e0e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x69/0x120 fs/exfat/inode.c:96 4 locks held by kworker/u4:8/1095: #0: ffff888015266138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #0: ffff888015266138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2703 #1: ffffc90004597d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #1: ffffc90004597d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2703 #2: ffff88806d47a0e0 (&type->s_umount_key#54){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:610 #3: ffff888028aba0e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x69/0x120 fs/exfat/inode.c:96 4 locks held by kworker/u4:9/2405: #0: ffff888015266138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #0: ffff888015266138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2703 #1: ffffc90009677d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2605 [inline] #1: ffffc90009677d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2703 #2: ffff8880618720e0 (&type->s_umount_key#54){++++}-{3:3}, at: super_trylock_shared+0x22/0xf0 fs/super.c:610 #3: ffff88807024c0e0 (&sbi->s_lock){+.+.}-{3:3}, at: exfat_write_inode+0x69/0x120 fs/exfat/inode.c:96 1 lock held by udevd/4515: 2 locks held by getty/4812: #0: ffff88801b8380a0 (&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 6 locks held by syz-executor.2/5612: 6 locks held by syz-executor.0/5646: 6 locks held by syz-executor.4/5678: 6 locks held by syz-executor.1/5686: 6 locks held by syz-executor.3/5690: 6 locks held by syz-executor.5/5695: 1 lock held by syz-executor.2/5891: 1 lock held by syz-executor.4/7541: 1 lock held by syz-executor.1/7544: #0: ffff8880b983c358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 1 lock held by syz-executor.0/7546: 3 locks held by syz-executor.2/7547: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 30 Comm: khungtaskd Not tainted 6.7.0-rc3-syzkaller-00033-g3b47bc037bd4 #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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2461 Comm: kworker/u4:12 Not tainted 6.7.0-rc3-syzkaller-00033-g3b47bc037bd4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:kasan_quarantine_put+0x2f/0x230 mm/kasan/quarantine.c:215 Code: 57 41 56 41 55 41 54 53 50 49 89 fe e8 9a ee ff ff 48 85 c0 74 6b 48 89 c3 48 c7 04 24 00 00 00 00 9c 8f 04 24 4c 8b 3c 24 fa <41> f7 c7 00 02 00 00 74 05 e8 43 d1 aa ff e8 ce 76 2c 09 89 c0 48 RSP: 0018:ffffc900095c7aa0 EFLAGS: 00000082 RAX: ffff88801d705140 RBX: ffff88801d705140 RCX: 0000000000000000 RDX: ffff88801d705140 RSI: ffff88801d705140 RDI: ffff888142e64640 RBP: 0000000000000000 R08: 000000000000000b R09: ffffffff813db4e7 R10: 0000000000000002 R11: ffff888025953b80 R12: 0000000000000000 R13: ffffffff8a8f005c R14: ffff888142e64640 R15: 0000000000000282 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffeb468be08 CR3: 0000000061ce4000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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:435 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0x90f/0x1420 kernel/workqueue.c:2703 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2784 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