RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000009 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000a R13: 000000000000009b R14: 00000000004c2f07 R15: 0000000000000000 ====================================================== WARNING: possible circular locking dependency detected 4.14.172-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/11748 is trying to acquire lock: (console_owner){-.-.}, at: [] console_trylock_spinning kernel/printk/printk.c:1658 [inline] (console_owner){-.-.}, at: [] vprintk_emit kernel/printk/printk.c:1922 [inline] (console_owner){-.-.}, at: [] vprintk_emit+0x2f0/0x600 kernel/printk/printk.c:1888 but task is already holding lock: (&(&pool->lock)->rlock){-.-.}, at: [] spin_lock include/linux/spinlock.h:317 [inline] (&(&pool->lock)->rlock){-.-.}, at: [] start_flush_work kernel/workqueue.c:2831 [inline] (&(&pool->lock)->rlock){-.-.}, at: [] flush_work+0x134/0x780 kernel/workqueue.c:2890 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&(&pool->lock)->rlock){-.-.}: __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152 spin_lock include/linux/spinlock.h:317 [inline] __queue_work+0x1ba/0xf10 kernel/workqueue.c:1419 queue_work_on+0x159/0x1d0 kernel/workqueue.c:1488 queue_work include/linux/workqueue.h:491 [inline] schedule_work include/linux/workqueue.h:549 [inline] put_pwq kernel/workqueue.c:1092 [inline] put_pwq+0x129/0x180 kernel/workqueue.c:1077 put_pwq_unlocked.part.0+0x30/0x70 kernel/workqueue.c:1109 put_pwq_unlocked kernel/workqueue.c:1103 [inline] destroy_workqueue+0x570/0x660 kernel/workqueue.c:4171 do_floppy_init drivers/block/floppy.c:4732 [inline] floppy_async_init+0x1abb/0x1c06 drivers/block/floppy.c:4749 async_run_entry_fn+0x102/0x4c0 kernel/async.c:127 process_one_work+0x813/0x1540 kernel/workqueue.c:2114 worker_thread+0x5d1/0x1070 kernel/workqueue.c:2248 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 -> #3 (&pool->lock/1){..-.}: __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152 spin_lock include/linux/spinlock.h:317 [inline] __queue_work+0x1ba/0xf10 kernel/workqueue.c:1419 queue_work_on+0x159/0x1d0 kernel/workqueue.c:1488 pty_write+0x173/0x1c0 drivers/tty/pty.c:125 n_tty_write+0x8dd/0xe30 drivers/tty/n_tty.c:2356 do_tty_write drivers/tty/tty_io.c:959 [inline] tty_write+0x3f0/0x700 drivers/tty/tty_io.c:1043 __vfs_write+0xe4/0x630 fs/read_write.c:480 vfs_write+0x192/0x4e0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #2 (&(&port->lock)->rlock){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x8c/0xbf kernel/locking/spinlock.c:160 tty_port_tty_get+0x1d/0x80 drivers/tty/tty_port.c:288 tty_port_default_wakeup+0x11/0x40 drivers/tty/tty_port.c:46 serial8250_tx_chars+0x400/0x9e0 drivers/tty/serial/8250/8250_port.c:1810 serial8250_handle_irq.part.0+0x1f8/0x240 drivers/tty/serial/8250/8250_port.c:1883 serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1869 [inline] serial8250_default_handle_irq+0x96/0x110 drivers/tty/serial/8250/8250_port.c:1899 serial8250_interrupt+0xe4/0x1a0 drivers/tty/serial/8250/8250_core.c:129 __handle_irq_event_percpu+0x125/0x7e0 kernel/irq/handle.c:147 handle_irq_event_percpu+0x66/0x120 kernel/irq/handle.c:187 handle_irq_event+0xa2/0x12d kernel/irq/handle.c:204 handle_edge_irq+0x215/0x810 kernel/irq/chip.c:770 generic_handle_irq_desc include/linux/irqdesc.h:159 [inline] handle_irq+0x35/0x50 arch/x86/kernel/irq_64.c:87 do_IRQ+0x93/0x1d0 arch/x86/kernel/irq.c:230 ret_from_intr+0x0/0x1e arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irqrestore+0x91/0xe0 kernel/locking/spinlock.c:192 spin_unlock_irqrestore include/linux/spinlock.h:372 [inline] uart_write+0x28c/0x4e0 drivers/tty/serial/serial_core.c:625 process_output_block drivers/tty/n_tty.c:595 [inline] n_tty_write+0x375/0xe30 drivers/tty/n_tty.c:2333 do_tty_write drivers/tty/tty_io.c:959 [inline] tty_write+0x3f0/0x700 drivers/tty/tty_io.c:1043 redirected_tty_write+0x9c/0xb0 drivers/tty/tty_io.c:1064 __vfs_write+0xe4/0x630 fs/read_write.c:480 vfs_write+0x192/0x4e0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #1 (&port_lock_key){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x8c/0xbf kernel/locking/spinlock.c:160 serial8250_console_write+0x6c1/0x8e0 drivers/tty/serial/8250/8250_port.c:3236 call_console_drivers kernel/printk/printk.c:1725 [inline] console_unlock+0x9b2/0xec0 kernel/printk/printk.c:2397 vprintk_emit kernel/printk/printk.c:1923 [inline] vprintk_emit+0x1f8/0x600 kernel/printk/printk.c:1888 vprintk_func+0x58/0x152 kernel/printk/printk_safe.c:401 printk+0x9e/0xbc kernel/printk/printk.c:1996 register_console+0x5ec/0x9a0 kernel/printk/printk.c:2716 univ8250_console_init+0x2f/0x3a drivers/tty/serial/8250/8250_core.c:691 console_init+0x46/0x53 kernel/printk/printk.c:2797 start_kernel+0x437/0x676 init/main.c:634 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:240 -> #0 (console_owner){-.-.}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3994 console_trylock_spinning kernel/printk/printk.c:1679 [inline] vprintk_emit kernel/printk/printk.c:1922 [inline] vprintk_emit+0x32d/0x600 kernel/printk/printk.c:1888 vprintk_func+0x58/0x152 kernel/printk/printk_safe.c:401 printk+0x9e/0xbc kernel/printk/printk.c:1996 fail_dump lib/fault-inject.c:44 [inline] should_fail.cold+0xdf/0x14b lib/fault-inject.c:149 should_failslab+0xd6/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] kmem_cache_alloc+0x44/0x770 mm/slab.c:3550 kmem_cache_zalloc include/linux/slab.h:651 [inline] fill_pool lib/debugobjects.c:110 [inline] __debug_object_init+0x5b7/0x830 lib/debugobjects.c:341 __init_work kernel/workqueue.c:504 [inline] insert_wq_barrier kernel/workqueue.c:2498 [inline] start_flush_work kernel/workqueue.c:2846 [inline] flush_work+0x1f7/0x780 kernel/workqueue.c:2890 __cancel_work_timer+0x2d0/0x460 kernel/workqueue.c:2962 uhid_dev_destroy+0x6e/0x100 drivers/hid/uhid.c:568 uhid_char_release+0x4c/0xa0 drivers/hid/uhid.c:645 __fput+0x25f/0x790 fs/file_table.c:210 task_work_run+0x113/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1d6/0x220 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x42/0xb7 other info that might help us debug this: Chain exists of: console_owner --> &pool->lock/1 --> &(&pool->lock)->rlock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&(&pool->lock)->rlock); lock(&pool->lock/1); lock(&(&pool->lock)->rlock); lock(console_owner); *** DEADLOCK *** 1 lock held by syz-executor.0/11748: #0: (&(&pool->lock)->rlock){-.-.}, at: [] spin_lock include/linux/spinlock.h:317 [inline] #0: (&(&pool->lock)->rlock){-.-.}, at: [] start_flush_work kernel/workqueue.c:2831 [inline] #0: (&(&pool->lock)->rlock){-.-.}, at: [] flush_work+0x134/0x780 kernel/workqueue.c:2890 stack backtrace: CPU: 1 PID: 11748 Comm: syz-executor.0 Not tainted 4.14.172-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x13e/0x194 lib/dump_stack.c:58 print_circular_bug.isra.0.cold+0x1c4/0x282 kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1901 [inline] check_prevs_add kernel/locking/lockdep.c:2018 [inline] validate_chain kernel/locking/lockdep.c:2460 [inline] __lock_acquire+0x2cb3/0x4620 kernel/locking/lockdep.c:3487 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3994 console_trylock_spinning kernel/printk/printk.c:1679 [inline] vprintk_emit kernel/printk/printk.c:1922 [inline] vprintk_emit+0x32d/0x600 kernel/printk/printk.c:1888 vprintk_func+0x58/0x152 kernel/printk/printk_safe.c:401 printk+0x9e/0xbc kernel/printk/printk.c:1996 fail_dump lib/fault-inject.c:44 [inline] should_fail.cold+0xdf/0x14b lib/fault-inject.c:149 should_failslab+0xd6/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] kmem_cache_alloc+0x44/0x770 mm/slab.c:3550 kmem_cache_zalloc include/linux/slab.h:651 [inline] fill_pool lib/debugobjects.c:110 [inline] __debug_object_init+0x5b7/0x830 lib/debugobjects.c:341 __init_work kernel/workqueue.c:504 [inline] insert_wq_barrier kernel/workqueue.c:2498 [inline] start_flush_work kernel/workqueue.c:2846 [inline] flush_work+0x1f7/0x780 kernel/workqueue.c:2890 __cancel_work_timer+0x2d0/0x460 kernel/workqueue.c:2962 uhid_dev_destroy+0x6e/0x100 drivers/hid/uhid.c:568 uhid_char_release+0x4c/0xa0 drivers/hid/uhid.c:645 __fput+0x25f/0x790 fs/file_table.c:210 task_work_run+0x113/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1d6/0x220 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45c479 RSP: 002b:00007fe423e3ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000021 RAX: 0000000000000008 RBX: 00007fe423e3f6d4 RCX: 000000000045c479 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000009 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000a R13: 000000000000009b R14: 00000000004c2f07 R15: 0000000000000000 hid-generic: probe of 0000:0000:0000.016C failed with error -22 hid-generic 0000:0000:0000.016D: unknown main item tag 0x0 ceph: No mds server is up or the cluster is laggy hid-generic 0000:0000:0000.016D: hidraw0: HID v0.00 Device [syz0] on syz0 libceph: mon1 [::6]:6789 socket closed (con state CONNECTING) hid-generic 0000:0000:0000.016E: unknown main item tag 0x0 hid-generic 0000:0000:0000.016E: unknown main item tag 0x0 hid-generic 0000:0000:0000.016E: unknown main item tag 0x0 hid-generic 0000:0000:0000.016E: hidraw0: HID v0.00 Device [syz0] on syz0 ceph: No mds server is up or the cluster is laggy hid-generic 0000:0000:0000.016F: unknown main item tag 0x0 hid-generic 0000:0000:0000.016F: unknown main item tag 0x0 hid-generic 0000:0000:0000.0170: unknown main item tag 0x0 hid-generic 0000:0000:0000.0170: unknown main item tag 0x0 hid-generic 0000:0000:0000.016F: unknown main item tag 0x0 hid-generic 0000:0000:0000.0170: unknown main item tag 0x0 hid-generic 0000:0000:0000.0170: hidraw0: HID v0.00 Device [syz0] on syz0 hid-generic 0000:0000:0000.016F: hidraw1: HID v0.00 Device [syz0] on syz0 libceph: resolve '0Ô' (ret=-3): failed hid-generic 0000:0000:0000.0171: unknown main item tag 0x0 libceph: parse_ips bad ip '[d::],0Ô:6' hid-generic 0000:0000:0000.0171: unknown main item tag 0x0 hid-generic 0000:0000:0000.0172: unknown main item tag 0x0 libceph: resolve '0Ô' (ret=-3): failed hid-generic 0000:0000:0000.0172: unknown main item tag 0x0 libceph: parse_ips bad ip '[d::],0Ô:6' hid-generic 0000:0000:0000.0171: unknown main item tag 0x0 hid-generic 0000:0000:0000.0172: unknown main item tag 0x0 hid-generic 0000:0000:0000.0171: hidraw1: HID v0.00 Device [syz0] on syz0 libceph: connect [d::]:6789 error -101 libceph: mon0 [d::]:6789 connect error hid-generic 0000:0000:0000.0172: hidraw2: HID v0.00 Device [syz0] on syz0 ceph: No mds server is up or the cluster is laggy libceph: connect [d::]:6789 error -101 libceph: mon0 [d::]:6789 connect error ceph: No mds server is up or the cluster is laggy libceph: connect [d::]:6789 error -101 libceph: mon0 [d::]:6789 connect error ceph: No mds server is up or the cluster is laggy libceph: mon1 [::6]:6789 socket closed (con state CONNECTING) libceph: connect [d::]:6789 error -101 libceph: mon0 [d::]:6789 connect error libceph: connect [d::]:6789 error -101 libceph: mon0 [d::]:6789 connect error kauditd_printk_skb: 12663 callbacks suppressed audit: type=1326 audit(1583032743.071:2178439): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=11814 comm="syz-executor.4" exe="/root/syz-executor.4" sig=0 arch=c000003e syscall=1 compat=0 ip=0x415f51 code=0x50000 audit: type=1326 audit(1583032743.051:2178337): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=11814 comm="syz-executor.4" exe="/root/syz-executor.4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x45c479 code=0x50000 audit: type=1326 audit(1583032743.081:2178440): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=11814 comm="syz-executor.4" exe="/root/syz-executor.4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x45c479 code=0x50000 audit: type=1326 audit(1583032743.081:2178441): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=11814 comm="syz-executor.4" exe="/root/syz-executor.4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x45c479 code=0x50000 audit: type=1326 audit(1583032743.081:2178442): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=11814 comm="syz-executor.4" exe="/root/syz-executor.4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x45c479 code=0x50000 audit: type=1326 audit(1583032743.081:2178443): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=11814 comm="syz-executor.4" exe="/root/syz-executor.4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x45c479 code=0x50000 audit: type=1326 audit(1583032743.081:2178444): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=11814 comm="syz-executor.4" exe="/root/syz-executor.4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x45c479 code=0x50000 audit: type=1326 audit(1583032743.081:2178445): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=11814 comm="syz-executor.4" exe="/root/syz-executor.4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x45c479 code=0x50000 audit: type=1326 audit(1583032743.081:2178446): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=11814 comm="syz-executor.4" exe="/root/syz-executor.4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x45c479 code=0x50000 audit: type=1326 audit(1583032743.081:2178447): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=11814 comm="syz-executor.4" exe="/root/syz-executor.4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x45c479 code=0x50000 libceph: connect [d::]:6789 error -101 libceph: mon0 [d::]:6789 connect error libceph: mon1 [::6]:6789 socket closed (con state CONNECTING) libceph: connect [d::]:6789 error -101 libceph: mon0 [d::]:6789 connect error