Hello, syzbot found the following issue on: HEAD commit: d1d2220c Add linux-next specific files for 20200924 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=14cd5cd3900000 kernel config: https://syzkaller.appspot.com/x/.config?x=254e028a642027c dashboard link: https://syzkaller.appspot.com/bug?extid=28abd693db9e92c160d8 compiler: gcc (GCC) 10.1.0-syz 20200507 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13ba3881900000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+28abd693db9e92c160d8@xxxxxxxxxxxxxxxxxxxxxxxxx ============================================ WARNING: possible recursive locking detected 5.9.0-rc6-next-20200924-syzkaller #0 Not tainted -------------------------------------------- kworker/0:1/12 is trying to acquire lock: ffff88808d998130 (&runtime->sleep){..-.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline] ffff88808d998130 (&runtime->sleep){..-.}-{2:2}, at: io_poll_double_wake+0x156/0x510 fs/io_uring.c:4855 but task is already holding lock: ffff888093f4c130 (&runtime->sleep){..-.}-{2:2}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:122 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&runtime->sleep); lock(&runtime->sleep); *** DEADLOCK *** May be due to missing lock nesting notation 6 locks held by kworker/0:1/12: #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2240 #1: ffffc90000d2fda8 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x854/0x15a0 kernel/workqueue.c:2244 #2: ffffffff8b6c5648 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:250 #3: ffffffff8a553d40 (rcu_read_lock){....}-{1:2}, at: ib_device_get_by_netdev+0x0/0x4f0 drivers/infiniband/core/device.c:2550 #4: ffff888214d31908 (&group->lock){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0x9f/0xd0 sound/core/pcm_native.c:170 #5: ffff888093f4c130 (&runtime->sleep){..-.}-{2:2}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:122 stack backtrace: CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.9.0-rc6-next-20200924-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events linkwatch_event Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x198/0x1fb lib/dump_stack.c:118 print_deadlock_bug kernel/locking/lockdep.c:2714 [inline] check_deadlock kernel/locking/lockdep.c:2755 [inline] validate_chain kernel/locking/lockdep.c:3546 [inline] __lock_acquire.cold+0x12e/0x3ad kernel/locking/lockdep.c:4796 lock_acquire+0x1f2/0xaa0 kernel/locking/lockdep.c:5398 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] io_poll_double_wake+0x156/0x510 fs/io_uring.c:4855 __wake_up_common+0x147/0x650 kernel/sched/wait.c:93 __wake_up_common_lock+0xd0/0x130 kernel/sched/wait.c:123 snd_pcm_update_state+0x46a/0x540 sound/core/pcm_lib.c:203 snd_pcm_update_hw_ptr0+0xa71/0x1a50 sound/core/pcm_lib.c:464 snd_pcm_period_elapsed+0x160/0x250 sound/core/pcm_lib.c:1805 dummy_hrtimer_callback+0x94/0x1b0 sound/drivers/dummy.c:378 __run_hrtimer kernel/time/hrtimer.c:1524 [inline] __hrtimer_run_queues+0x693/0xea0 kernel/time/hrtimer.c:1588 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1605 __do_softirq+0x203/0xab6 kernel/softirq.c:298 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:786 </IRQ> __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0x9d/0xd0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0x235/0x280 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:653 [inline] RIP: 0010:lock_acquire+0x27b/0xaa0 kernel/locking/lockdep.c:5401 Code: 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 d2 06 00 00 48 83 3d 89 bc e1 08 00 0f 84 2d 05 00 00 48 8b 3c 24 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 RSP: 0018:ffffc90000d2f8c8 EFLAGS: 00000282 RAX: 1ffffffff1479e35 RBX: 1ffff920001a5f1c RCX: 00000000f1571e19 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000282 RBP: ffff8880a969a300 R08: 0000000000000000 R09: ffffffff8d71a9e7 R10: fffffbfff1ae353c R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: ffffffff8a553d40 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:253 [inline] rcu_read_lock include/linux/rcupdate.h:642 [inline] ib_device_get_by_netdev+0x9a/0x4f0 drivers/infiniband/core/device.c:2248 rxe_get_dev_from_net drivers/infiniband/sw/rxe/rxe.h:76 [inline] rxe_notify+0x8b/0x1c0 drivers/infiniband/sw/rxe/rxe_net.c:566 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2034 netdev_state_change net/core/dev.c:1464 [inline] netdev_state_change+0x100/0x130 net/core/dev.c:1457 linkwatch_do_dev+0x13f/0x180 net/core/link_watch.c:167 __linkwatch_run_queue+0x1ea/0x630 net/core/link_watch.c:212 linkwatch_event+0x4a/0x60 net/core/link_watch.c:251 process_one_work+0x933/0x15a0 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 --- This report is generated by a bot. 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