====================================================== WARNING: possible circular locking dependency detected 6.1.0-rc7-syzkaller #0 Not tainted ------------------------------------------------------ kworker/3:3/3119 is trying to acquire lock: ffff88802c93a9d8 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x367/0x13b0 kernel/workqueue.c:1474 but task is already holding lock: ffff88801ea03528 (&tty->write_wait){-...}-{2:2}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:136 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&tty->write_wait){-...}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:136 tty_port_default_wakeup+0x2a/0x40 drivers/tty/tty_port.c:71 serial8250_tx_chars+0x503/0xdb0 drivers/tty/serial/8250/8250_port.c:1859 __start_tx drivers/tty/serial/8250/8250_port.c:1575 [inline] serial8250_start_tx+0x6d5/0x850 drivers/tty/serial/8250/8250_port.c:1681 __uart_start.isra.0+0x16b/0x1b0 drivers/tty/serial/serial_core.c:141 uart_write+0x2ff/0x570 drivers/tty/serial/serial_core.c:601 process_output_block drivers/tty/n_tty.c:586 [inline] n_tty_write+0x4ce/0xfd0 drivers/tty/n_tty.c:2350 do_tty_write drivers/tty/tty_io.c:1018 [inline] file_tty_write.constprop.0+0x452/0x890 drivers/tty/tty_io.c:1089 redirected_tty_write+0xa5/0xc0 drivers/tty/tty_io.c:1110 call_write_iter include/linux/fs.h:2199 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x9ed/0xdd0 fs/read_write.c:584 ksys_write+0x12b/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #3 (&port_lock_key){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 serial8250_console_write+0x4ba/0x1010 drivers/tty/serial/8250/8250_port.c:3395 call_console_driver kernel/printk/printk.c:1942 [inline] console_emit_next_record.constprop.0+0x3de/0x840 kernel/printk/printk.c:2731 console_flush_all kernel/printk/printk.c:2793 [inline] console_unlock+0x3c2/0x600 kernel/printk/printk.c:2860 vprintk_emit+0x1bd/0x600 kernel/printk/printk.c:2268 vprintk+0x84/0xa0 kernel/printk/printk_safe.c:50 _printk+0xbe/0xf1 kernel/printk/printk.c:2289 register_console kernel/printk/printk.c:3208 [inline] register_console+0x45e/0x820 kernel/printk/printk.c:3103 univ8250_console_init+0x3e/0x4a drivers/tty/serial/8250/8250_core.c:687 console_init+0x3bb/0x582 kernel/printk/printk.c:3298 start_kernel+0x303/0x498 init/main.c:1073 secondary_startup_64_no_verify+0xce/0xdb -> #2 (console_owner){....}-{0:0}: console_lock_spinning_enable kernel/printk/printk.c:1805 [inline] console_emit_next_record.constprop.0+0x2dd/0x840 kernel/printk/printk.c:2728 console_flush_all kernel/printk/printk.c:2793 [inline] console_unlock+0x3c2/0x600 kernel/printk/printk.c:2860 vprintk_emit+0x1bd/0x600 kernel/printk/printk.c:2268 vprintk+0x84/0xa0 kernel/printk/printk_safe.c:50 _printk+0xbe/0xf1 kernel/printk/printk.c:2289 build_zonelists.cold+0xe5/0x11f mm/page_alloc.c:6506 __build_all_zonelists+0x122/0x180 mm/page_alloc.c:6619 build_all_zonelists_init+0x35/0x12f mm/page_alloc.c:6644 build_all_zonelists+0x123/0x140 mm/page_alloc.c:6677 start_kernel+0xbd/0x498 init/main.c:967 secondary_startup_64_no_verify+0xce/0xdb -> #1 (zonelist_update_seq.seqcount){...-}-{0:0}: seqcount_lockdep_reader_access include/linux/seqlock.h:102 [inline] read_seqbegin include/linux/seqlock.h:836 [inline] zonelist_iter_begin mm/page_alloc.c:4730 [inline] __alloc_pages_slowpath.constprop.0+0x1ae/0x23d0 mm/page_alloc.c:5052 __alloc_pages+0x4aa/0x5b0 mm/page_alloc.c:5571 __alloc_pages_node include/linux/gfp.h:223 [inline] kmem_getpages mm/slab.c:1363 [inline] cache_grow_begin+0x75/0x360 mm/slab.c:2570 cache_alloc_refill+0x27f/0x380 mm/slab.c:2943 ____cache_alloc mm/slab.c:3019 [inline] ____cache_alloc mm/slab.c:3002 [inline] __do_cache_alloc mm/slab.c:3202 [inline] slab_alloc_node mm/slab.c:3250 [inline] slab_alloc mm/slab.c:3265 [inline] __kmem_cache_alloc_lru mm/slab.c:3442 [inline] kmem_cache_alloc+0x364/0x460 mm/slab.c:3461 kmem_cache_zalloc include/linux/slab.h:679 [inline] fill_pool+0x264/0x5c0 lib/debugobjects.c:168 __debug_object_init+0x7a/0xd10 lib/debugobjects.c:562 debug_object_init lib/debugobjects.c:617 [inline] debug_object_activate+0x330/0x3e0 lib/debugobjects.c:703 debug_work_activate kernel/workqueue.c:510 [inline] __queue_work+0x682/0x13b0 kernel/workqueue.c:1516 queue_work_on+0xf2/0x110 kernel/workqueue.c:1545 queue_work include/linux/workqueue.h:503 [inline] schedule_work include/linux/workqueue.h:564 [inline] wireless_send_event+0x6de/0xc40 net/wireless/wext-core.c:635 __cfg80211_ibss_joined+0x41d/0x540 net/wireless/ibss.c:56 cfg80211_process_wdev_events+0x391/0x5e0 net/wireless/util.c:986 cfg80211_process_rdev_events+0x9f/0x130 net/wireless/util.c:1012 cfg80211_event_work+0x2b/0x40 net/wireless/core.c:328 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 -> #0 (&pool->lock){-.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 __queue_work+0x367/0x13b0 kernel/workqueue.c:1474 queue_work_on+0xf2/0x110 kernel/workqueue.c:1545 queue_work include/linux/workqueue.h:503 [inline] schedule_work include/linux/workqueue.h:564 [inline] p9_pollwake+0xc1/0x1d0 net/9p/trans_fd.c:540 __wake_up_common+0x147/0x650 kernel/sched/wait.c:107 __wake_up_common_lock+0xd0/0x130 kernel/sched/wait.c:137 tty_write_unlock drivers/tty/tty_io.c:939 [inline] do_tty_write drivers/tty/tty_io.c:1043 [inline] file_tty_write.constprop.0+0x504/0x890 drivers/tty/tty_io.c:1089 __kernel_write_iter+0x262/0x730 fs/read_write.c:517 __kernel_write fs/read_write.c:537 [inline] kernel_write fs/read_write.c:558 [inline] kernel_write+0x1c1/0x630 fs/read_write.c:548 p9_fd_write net/9p/trans_fd.c:434 [inline] p9_write_work+0x25a/0xc60 net/9p/trans_fd.c:485 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 other info that might help us debug this: Chain exists of: &pool->lock --> &port_lock_key --> &tty->write_wait Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&tty->write_wait); lock(&port_lock_key); lock(&tty->write_wait); lock(&pool->lock); *** DEADLOCK *** 5 locks held by kworker/3:3/3119: #0: ffff888012061d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888012061d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888012061d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888012061d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888012061d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888012061d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x86d/0x1710 kernel/workqueue.c:2260 #1: ffffc90003987da8 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1710 kernel/workqueue.c:2264 #2: ffff88801ea03098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:244 #3: ffff88801ea03528 (&tty->write_wait){-...}-{2:2}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:136 #4: ffffffff8c58cdc0 (rcu_read_lock){....}-{1:2}, at: __queue_work+0xca/0x13b0 kernel/workqueue.c:1437 stack backtrace: CPU: 3 PID: 3119 Comm: kworker/3:3 Not tainted 6.1.0-rc7-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Workqueue: events p9_write_work Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 __queue_work+0x367/0x13b0 kernel/workqueue.c:1474 queue_work_on+0xf2/0x110 kernel/workqueue.c:1545 queue_work include/linux/workqueue.h:503 [inline] schedule_work include/linux/workqueue.h:564 [inline] p9_pollwake+0xc1/0x1d0 net/9p/trans_fd.c:540 __wake_up_common+0x147/0x650 kernel/sched/wait.c:107 __wake_up_common_lock+0xd0/0x130 kernel/sched/wait.c:137 tty_write_unlock drivers/tty/tty_io.c:939 [inline] do_tty_write drivers/tty/tty_io.c:1043 [inline] file_tty_write.constprop.0+0x504/0x890 drivers/tty/tty_io.c:1089 __kernel_write_iter+0x262/0x730 fs/read_write.c:517 __kernel_write fs/read_write.c:537 [inline] kernel_write fs/read_write.c:558 [inline] kernel_write+0x1c1/0x630 fs/read_write.c:548 p9_fd_write net/9p/trans_fd.c:434 [inline] p9_write_work+0x25a/0xc60 net/9p/trans_fd.c:485 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306