Hello, While running syzkaller fuzzer on 0f98f121e1670eaa2a2fbb675e07d6ba7f0e146f of linux-next, I've for the following splash. Note there are 2 separate bugs (but maybe related):
BUG: sleeping function called from invalid context at drivers/tty/vt/vt.c:2195 [ INFO: possible irq lock inversion dependency detected ] BUG: sleeping function called from invalid context at drivers/tty/vt/vt.c:2195 in_atomic(): 1, irqs_disabled(): 1, pid: 11832, name: syz-executor 3 locks held by syz-executor/11832: #0: (&tty->ldisc_sem){++++++}, at: [<ffffffff86e0f837>] ldsem_down_write+0x37/0x3c drivers/tty/tty_ldsem.c:393 #1: (&(&gsm->control_lock)->rlock){......}, at: [<ffffffff8324c896>] gsm_control_send+0x1b6/0x460 drivers/tty/n_gsm.c:1374 #2: (&(&gsm->tx_lock)->rlock){......}, at: [<ffffffff8324a87a>] gsm_data_queue+0x3a/0xb0 drivers/tty/n_gsm.c:786 irq event stamp: 21728 hardirqs last enabled at (21727): [< inline >] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:162 hardirqs last enabled at (21727): [<ffffffff86e10441>] _raw_spin_unlock_irqrestore+0x31/0xc0 kernel/locking/spinlock.c:191 hardirqs last disabled at (21728): [< inline >] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 hardirqs last disabled at (21728): [<ffffffff86e102e8>] _raw_spin_lock_irqsave+0x78/0xd0 kernel/locking/spinlock.c:159 softirqs last enabled at (21418): [<ffffffff86e13c7c>] __do_softirq+0x6cc/0xa3e kernel/softirq.c:299 softirqs last disabled at (21393): [< inline >] invoke_softirq kernel/softirq.c:350 softirqs last disabled at (21393): [<ffffffff8139b4cf>] irq_exit+0x18f/0x1d0 kernel/softirq.c:391 CPU: 1 PID: 11832 Comm: syz-executor Not tainted 4.8.0-rc3-next-20160825+ #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 ffffffff886b6fe0 ffff8800612e72d8 ffffffff82db38d9 ffffffff6b47a680 fffffbfff10d6dfc ffff88006b47a680 0000000000002e38 0000000000000000 0000000000000000 ffff88003d8f9280 ffff8800612e7300 ffffffff8140d58b Call Trace: [< inline >] __dump_stack lib/dump_stack.c:15 [<ffffffff82db38d9>] dump_stack+0x12e/0x185 lib/dump_stack.c:51 [<ffffffff8140d58b>] ___might_sleep+0x27b/0x3a0 kernel/sched/core.c:7644 [<ffffffff8140d740>] __might_sleep+0x90/0x1a0 [<ffffffff83285a75>] do_con_write.part.22+0xa5/0x1c30 drivers/tty/vt/vt.c:2195 [< inline >] do_con_write drivers/tty/vt/vt.c:2778 [<ffffffff83287732>] con_write+0xb2/0xc0 drivers/tty/vt/vt.c:2774 [<ffffffff83248e3e>] gsmld_output+0xce/0x1a0 drivers/tty/n_gsm.c:2217 [<ffffffff83247db3>] gsm_data_kick+0x1f3/0x6d0 drivers/tty/n_gsm.c:708 [<ffffffff8324a50f>] __gsm_data_queue.isra.5+0x5af/0x8e0 drivers/tty/n_gsm.c:770 [<ffffffff8324a89f>] gsm_data_queue+0x5f/0xb0 drivers/tty/n_gsm.c:787 [<ffffffff8324c223>] gsm_control_transmit+0x193/0x220 drivers/tty/n_gsm.c:1315 [<ffffffff8324ca68>] gsm_control_send+0x388/0x460 drivers/tty/n_gsm.c:1385 [<ffffffff832502dd>] gsm_cleanup_mux+0x1cd/0x630 drivers/tty/n_gsm.c:2055 [< inline >] gsmld_detach_gsm drivers/tty/n_gsm.c:2267 [<ffffffff83251c63>] gsmld_close+0xc3/0x190 drivers/tty/n_gsm.c:2335 [<ffffffff83239a19>] tty_ldisc_close.isra.2+0x99/0xe0 drivers/tty/tty_ldisc.c:487 [<ffffffff83239aab>] tty_ldisc_kill+0x4b/0xc0 drivers/tty/tty_ldisc.c:619 [<ffffffff8323afb3>] tty_ldisc_release+0x1b3/0x260 drivers/tty/tty_ldisc.c:787 [<ffffffff83222e41>] tty_release+0xad1/0x1310 drivers/tty/tty_io.c:1904 [<ffffffff81868bbc>] __fput+0x28c/0x780 fs/file_table.c:208 [<ffffffff81869135>] ____fput+0x15/0x20 fs/file_table.c:244 [<ffffffff813ebf63>] task_work_run+0xf3/0x170 [< inline >] exit_task_work include/linux/task_work.h:21 [<ffffffff81394218>] do_exit+0x868/0x2e70 kernel/exit.c:828 [<ffffffff81396998>] do_group_exit+0x108/0x330 kernel/exit.c:958 [<ffffffff813ba4aa>] get_signal+0x62a/0x15d0 kernel/signal.c:2307 [<ffffffff81202333>] do_signal+0x83/0x1f60 arch/x86/kernel/signal.c:805 [<ffffffff81006345>] exit_to_usermode_loop+0x1a5/0x210 arch/x86/entry/common.c:163 [< inline >] prepare_exit_to_usermode arch/x86/entry/common.c:198 [<ffffffff8100869f>] syscall_return_slowpath+0x2bf/0x340 arch/x86/entry/common.c:267 [<ffffffff86e1079c>] entry_SYSCALL_64_fastpath+0xbf/0xc1 ========================================================= [ INFO: possible irq lock inversion dependency detected ] 4.8.0-rc3-next-20160825+ #8 Tainted: G W --------------------------------------------------------- swapper/1/0 just changed the state of lock: (&(&gsm->control_lock)->rlock){..-...}, at: [<ffffffff8324c2d6>] gsm_control_retransmit+0x26/0x220 drivers/tty/n_gsm.c:1334 but this lock took another, SOFTIRQ-unsafe lock in the past: (console_lock){+.+.+.} other info that might help us debug this: Chain exists of: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(console_lock); local_irq_disable(); lock(&(&gsm->control_lock)->rlock); lock(&(&gsm->tx_lock)->rlock); <Interrupt> lock(&(&gsm->control_lock)->rlock); *** DEADLOCK *** 1 lock held by swapper/1/0: #0: (((&gsm->t2_timer))){+.-...}, at: [< inline >] lockdep_copy_map include/linux/lockdep.h:165 #0: (((&gsm->t2_timer))){+.-...}, at: [<ffffffff814fbe01>] call_timer_fn+0xd1/0x6d0 kernel/time/timer.c:1288 the shortest dependencies between 2nd lock and 1st lock: -> (console_lock){+.+.+.} ops: 4563 { HARDIRQ-ON-W at: [< inline >] mark_irqflags kernel/locking/lockdep.c:2934 [<ffffffff8149bf29>] __lock_acquire+0xd99/0x3410 kernel/locking/lockdep.c:3292 [<ffffffff8149f1eb>] lock_acquire+0x1db/0x450 kernel/locking/lockdep.c:3746 [<ffffffff814b3724>] console_lock+0x54/0x80 kernel/printk/printk.c:2224 [<ffffffff89705f5c>] con_init+0x17/0x5ac drivers/tty/vt/vt.c:2966 [<ffffffff8970456a>] console_init+0x4d/0x5d drivers/tty/tty_io.c:3585 [<ffffffff89642610>] start_kernel+0x3a3/0x660 init/main.c:587 [<ffffffff896412f4>] x86_64_start_reservations+0x38/0x3a arch/x86/kernel/head64.c:195 [<ffffffff8964144e>] x86_64_start_kernel+0x158/0x167 arch/x86/kernel/head64.c:176 SOFTIRQ-ON-W at: [< inline >] mark_irqflags kernel/locking/lockdep.c:2938 [<ffffffff8149bf8e>] __lock_acquire+0xdfe/0x3410 kernel/locking/lockdep.c:3292 [<ffffffff8149f1eb>] lock_acquire+0x1db/0x450 kernel/locking/lockdep.c:3746 [<ffffffff814b3724>] console_lock+0x54/0x80 kernel/printk/printk.c:2224 [<ffffffff89705f5c>] con_init+0x17/0x5ac drivers/tty/vt/vt.c:2966 [<ffffffff8970456a>] console_init+0x4d/0x5d drivers/tty/tty_io.c:3585 [<ffffffff89642610>] start_kernel+0x3a3/0x660 init/main.c:587 [<ffffffff896412f4>] x86_64_start_reservations+0x38/0x3a arch/x86/kernel/head64.c:195 [<ffffffff8964144e>] x86_64_start_kernel+0x158/0x167 arch/x86/kernel/head64.c:176 RECLAIM_FS-ON-W at: [<ffffffff8149a2e8>] mark_held_locks+0xc8/0x120 kernel/locking/lockdep.c:2657 [< inline >] __lockdep_trace_alloc kernel/locking/lockdep.c:2879 [<ffffffff814a0a77>] lockdep_trace_alloc+0x1f7/0x350 kernel/locking/lockdep.c:2894 [< inline >] slab_pre_alloc_hook mm/slab.h:392 [< inline >] slab_alloc mm/slab.c:3402 [<ffffffff81805701>] kmem_cache_alloc_trace+0x31/0x7a0 mm/slab.c:3642 [< inline >] kmalloc include/linux/slab.h:490 [< inline >] kzalloc include/linux/slab.h:636 [<ffffffff83832232>] device_create_groups_vargs+0x82/0x250 drivers/base/core.c:1691 [< inline >] device_create_vargs drivers/base/core.c:1749 [<ffffffff83832517>] device_create+0xb7/0xe0 drivers/base/core.c:1785 [<ffffffff896f3928>] fb_console_init+0x5b/0x1fd drivers/video/console/fbcon.c:3606 [<ffffffff81002310>] do_one_initcall+0xa0/0x2b0 init/main.c:778 [< inline >] do_initcall_level init/main.c:844 [< inline >] do_initcalls init/main.c:852 [< inline >] do_basic_setup init/main.c:870 [<ffffffff89642d43>] kernel_init_freeable+0x476/0x52f init/main.c:1017 [<ffffffff86df6283>] kernel_init+0x13/0x160 init/main.c:943 [<ffffffff86e1098a>] ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 INITIAL USE at: [<ffffffff8149b98b>] __lock_acquire+0x7fb/0x3410 kernel/locking/lockdep.c:3296 [<ffffffff8149f1eb>] lock_acquire+0x1db/0x450 kernel/locking/lockdep.c:3746 [<ffffffff814b3724>] console_lock+0x54/0x80 kernel/printk/printk.c:2224 [<ffffffff814b9d26>] register_console+0x3b6/0xb80 kernel/printk/printk.c:2725 [<ffffffff81378e98>] early_console_register+0xce/0xd3 arch/x86/kernel/early_printk.c:331 [<ffffffff8968298a>] setup_early_printk+0x14a/0x614 arch/x86/kernel/early_printk.c:350 [<ffffffff89641ab6>] do_early_param+0xc4/0x12a init/main.c:422 [< inline >] parse_one kernel/params.c:156 [<ffffffff813efcaf>] parse_args+0x64f/0xb70 kernel/params.c:243 [<ffffffff89642203>] parse_early_options+0x2d/0x35 init/main.c:432 [<ffffffff89642246>] parse_early_param+0x3b/0x4c init/main.c:447 [<ffffffff896657e3>] setup_arch+0x68a/0x17a9 arch/x86/kernel/setup.c:986 [<ffffffff8964230b>] start_kernel+0x9e/0x660 init/main.c:505 [<ffffffff896412f4>] x86_64_start_reservations+0x38/0x3a arch/x86/kernel/head64.c:195 [<ffffffff8964144e>] x86_64_start_kernel+0x158/0x167 arch/x86/kernel/head64.c:176 } ... key at: [<ffffffff887384a0>] console_lock_dep_map+0x0/0x40 ... acquired at: [<ffffffff8149f1eb>] lock_acquire+0x1db/0x450 kernel/locking/lockdep.c:3746 [<ffffffff814b3724>] console_lock+0x54/0x80 kernel/printk/printk.c:2224 [<ffffffff83285a7f>] do_con_write.part.22+0xaf/0x1c30 drivers/tty/vt/vt.c:2197 [< inline >] do_con_write drivers/tty/vt/vt.c:2778 [<ffffffff83287732>] con_write+0xb2/0xc0 drivers/tty/vt/vt.c:2774 [<ffffffff83248e3e>] gsmld_output+0xce/0x1a0 drivers/tty/n_gsm.c:2217 [<ffffffff83247db3>] gsm_data_kick+0x1f3/0x6d0 drivers/tty/n_gsm.c:708 [<ffffffff8324a50f>] __gsm_data_queue.isra.5+0x5af/0x8e0 drivers/tty/n_gsm.c:770 [<ffffffff8324a89f>] gsm_data_queue+0x5f/0xb0 drivers/tty/n_gsm.c:787 [<ffffffff8324c223>] gsm_control_transmit+0x193/0x220 drivers/tty/n_gsm.c:1315 [<ffffffff8324ca68>] gsm_control_send+0x388/0x460 drivers/tty/n_gsm.c:1385 [<ffffffff832502dd>] gsm_cleanup_mux+0x1cd/0x630 drivers/tty/n_gsm.c:2055 [< inline >] gsmld_detach_gsm drivers/tty/n_gsm.c:2267 [<ffffffff83251c63>] gsmld_close+0xc3/0x190 drivers/tty/n_gsm.c:2335 [<ffffffff83239a19>] tty_ldisc_close.isra.2+0x99/0xe0 drivers/tty/tty_ldisc.c:487 [<ffffffff83239aab>] tty_ldisc_kill+0x4b/0xc0 drivers/tty/tty_ldisc.c:619 [<ffffffff8323afb3>] tty_ldisc_release+0x1b3/0x260 drivers/tty/tty_ldisc.c:787 [<ffffffff83222e41>] tty_release+0xad1/0x1310 drivers/tty/tty_io.c:1904 [<ffffffff81868bbc>] __fput+0x28c/0x780 fs/file_table.c:208 [<ffffffff81869135>] ____fput+0x15/0x20 fs/file_table.c:244 [<ffffffff813ebf63>] task_work_run+0xf3/0x170 [< inline >] exit_task_work include/linux/task_work.h:21 [<ffffffff81394218>] do_exit+0x868/0x2e70 kernel/exit.c:828 [<ffffffff81396998>] do_group_exit+0x108/0x330 kernel/exit.c:958 [<ffffffff813ba4aa>] get_signal+0x62a/0x15d0 kernel/signal.c:2307 [<ffffffff81202333>] do_signal+0x83/0x1f60 arch/x86/kernel/signal.c:805 [<ffffffff81006345>] exit_to_usermode_loop+0x1a5/0x210 arch/x86/entry/common.c:163 [< inline >] prepare_exit_to_usermode arch/x86/entry/common.c:198 [<ffffffff8100869f>] syscall_return_slowpath+0x2bf/0x340 arch/x86/entry/common.c:267 [<ffffffff86e1079c>] entry_SYSCALL_64_fastpath+0xbf/0xc1 -> (&(&gsm->tx_lock)->rlock){......} ops: 1 { INITIAL USE at: [<ffffffff8149b98b>] __lock_acquire+0x7fb/0x3410 kernel/locking/lockdep.c:3296 [<ffffffff8149f1eb>] lock_acquire+0x1db/0x450 kernel/locking/lockdep.c:3746 [< inline >] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:112 [<ffffffff86e1030f>] _raw_spin_lock_irqsave+0x9f/0xd0 kernel/locking/spinlock.c:159 [<ffffffff8324a87a>] gsm_data_queue+0x3a/0xb0 drivers/tty/n_gsm.c:786 [<ffffffff8324c223>] gsm_control_transmit+0x193/0x220 drivers/tty/n_gsm.c:1315 [<ffffffff8324ca68>] gsm_control_send+0x388/0x460 drivers/tty/n_gsm.c:1385 [<ffffffff832502dd>] gsm_cleanup_mux+0x1cd/0x630 drivers/tty/n_gsm.c:2055 [< inline >] gsmld_detach_gsm drivers/tty/n_gsm.c:2267 [<ffffffff83251c63>] gsmld_close+0xc3/0x190 drivers/tty/n_gsm.c:2335 [<ffffffff83239a19>] tty_ldisc_close.isra.2+0x99/0xe0 drivers/tty/tty_ldisc.c:487 [<ffffffff83239aab>] tty_ldisc_kill+0x4b/0xc0 drivers/tty/tty_ldisc.c:619 [<ffffffff8323afb3>] tty_ldisc_release+0x1b3/0x260 drivers/tty/tty_ldisc.c:787 [<ffffffff83222e41>] tty_release+0xad1/0x1310 drivers/tty/tty_io.c:1904 [<ffffffff81868bbc>] __fput+0x28c/0x780 fs/file_table.c:208 [<ffffffff81869135>] ____fput+0x15/0x20 fs/file_table.c:244 [<ffffffff813ebf63>] task_work_run+0xf3/0x170 [< inline >] exit_task_work include/linux/task_work.h:21 [<ffffffff81394218>] do_exit+0x868/0x2e70 kernel/exit.c:828 [<ffffffff81396998>] do_group_exit+0x108/0x330 kernel/exit.c:958 [<ffffffff813ba4aa>] get_signal+0x62a/0x15d0 kernel/signal.c:2307 [<ffffffff81202333>] do_signal+0x83/0x1f60 arch/x86/kernel/signal.c:805 [<ffffffff81006345>] exit_to_usermode_loop+0x1a5/0x210 arch/x86/entry/common.c:163 [< inline >] prepare_exit_to_usermode arch/x86/entry/common.c:198 [<ffffffff8100869f>] syscall_return_slowpath+0x2bf/0x340 arch/x86/entry/common.c:267 [<ffffffff86e1079c>] entry_SYSCALL_64_fastpath+0xbf/0xc1 } ... key at: [<ffffffff8aef5fa0>] __key.52019+0x0/0x40 ... acquired at: [<ffffffff8149f1eb>] lock_acquire+0x1db/0x450 kernel/locking/lockdep.c:3746 [< inline >] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:112 [<ffffffff86e1030f>] _raw_spin_lock_irqsave+0x9f/0xd0 kernel/locking/spinlock.c:159 [<ffffffff8324a87a>] gsm_data_queue+0x3a/0xb0 drivers/tty/n_gsm.c:786 [<ffffffff8324c223>] gsm_control_transmit+0x193/0x220 drivers/tty/n_gsm.c:1315 [<ffffffff8324ca68>] gsm_control_send+0x388/0x460 drivers/tty/n_gsm.c:1385 [<ffffffff832502dd>] gsm_cleanup_mux+0x1cd/0x630 drivers/tty/n_gsm.c:2055 [< inline >] gsmld_detach_gsm drivers/tty/n_gsm.c:2267 [<ffffffff83251c63>] gsmld_close+0xc3/0x190 drivers/tty/n_gsm.c:2335 [<ffffffff83239a19>] tty_ldisc_close.isra.2+0x99/0xe0 drivers/tty/tty_ldisc.c:487 [<ffffffff83239aab>] tty_ldisc_kill+0x4b/0xc0 drivers/tty/tty_ldisc.c:619 [<ffffffff8323afb3>] tty_ldisc_release+0x1b3/0x260 drivers/tty/tty_ldisc.c:787 [<ffffffff83222e41>] tty_release+0xad1/0x1310 drivers/tty/tty_io.c:1904 [<ffffffff81868bbc>] __fput+0x28c/0x780 fs/file_table.c:208 [<ffffffff81869135>] ____fput+0x15/0x20 fs/file_table.c:244 [<ffffffff813ebf63>] task_work_run+0xf3/0x170 [< inline >] exit_task_work include/linux/task_work.h:21 [<ffffffff81394218>] do_exit+0x868/0x2e70 kernel/exit.c:828 [<ffffffff81396998>] do_group_exit+0x108/0x330 kernel/exit.c:958 [<ffffffff813ba4aa>] get_signal+0x62a/0x15d0 kernel/signal.c:2307 [<ffffffff81202333>] do_signal+0x83/0x1f60 arch/x86/kernel/signal.c:805 [<ffffffff81006345>] exit_to_usermode_loop+0x1a5/0x210 arch/x86/entry/common.c:163 [< inline >] prepare_exit_to_usermode arch/x86/entry/common.c:198 [<ffffffff8100869f>] syscall_return_slowpath+0x2bf/0x340 arch/x86/entry/common.c:267 [<ffffffff86e1079c>] entry_SYSCALL_64_fastpath+0xbf/0xc1 -> (&(&gsm->control_lock)->rlock){..-...} ops: 2 { IN-SOFTIRQ-W at: [< inline >] mark_irqflags kernel/locking/lockdep.c:2920 [<ffffffff8149bd74>] __lock_acquire+0xbe4/0x3410 kernel/locking/lockdep.c:3292 [<ffffffff8149f1eb>] lock_acquire+0x1db/0x450 kernel/locking/lockdep.c:3746 [< inline >] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:112 [<ffffffff86e1030f>] _raw_spin_lock_irqsave+0x9f/0xd0 kernel/locking/spinlock.c:159 [<ffffffff8324c2d6>] gsm_control_retransmit+0x26/0x220 drivers/tty/n_gsm.c:1334 [<ffffffff814fbe9e>] call_timer_fn+0x16e/0x6d0 kernel/time/timer.c:1298 [< inline >] expire_timers kernel/time/timer.c:1338 [< inline >] __run_timers kernel/time/timer.c:1627 [<ffffffff814fca46>] run_timer_softirq+0x646/0x1590 kernel/time/timer.c:1640 [<ffffffff86e1380c>] __do_softirq+0x25c/0xa3e kernel/softirq.c:273 [< inline >] invoke_softirq kernel/softirq.c:350 [<ffffffff8139b4cf>] irq_exit+0x18f/0x1d0 kernel/softirq.c:391 [< inline >] exiting_irq arch/x86/include/asm/apic.h:659 [<ffffffff86e1305b>] smp_apic_timer_interrupt+0x7b/0xa0 arch/x86/kernel/apic/apic.c:958 [<ffffffff86e1210c>] apic_timer_interrupt+0x8c/0xa0 arch/x86/entry/entry_64.S:487 [< inline >] arch_safe_halt arch/x86/include/asm/paravirt.h:107 [<ffffffff8121dcf2>] default_idle+0x52/0x370 arch/x86/kernel/process.c:308 [<ffffffff8121f36a>] arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:299 [<ffffffff8147bfd8>] default_idle_call+0x48/0xa0 kernel/sched/idle.c:93 [< inline >] cpuidle_idle_call kernel/sched/idle.c:151 [< inline >] cpu_idle_loop kernel/sched/idle.c:244 [<ffffffff8147c5c2>] cpu_startup_entry+0x592/0x7b0 kernel/sched/idle.c:293 [<ffffffff81269c2a>] start_secondary+0x2fa/0x410 arch/x86/kernel/smpboot.c:263 INITIAL USE at: [<ffffffff8149b98b>] __lock_acquire+0x7fb/0x3410 kernel/locking/lockdep.c:3296 [<ffffffff8149f1eb>] lock_acquire+0x1db/0x450 kernel/locking/lockdep.c:3746 [< inline >] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:112 [<ffffffff86e1030f>] _raw_spin_lock_irqsave+0x9f/0xd0 kernel/locking/spinlock.c:159 [<ffffffff8324c896>] gsm_control_send+0x1b6/0x460 drivers/tty/n_gsm.c:1374 [<ffffffff832502dd>] gsm_cleanup_mux+0x1cd/0x630 drivers/tty/n_gsm.c:2055 [< inline >] gsmld_detach_gsm drivers/tty/n_gsm.c:2267 [<ffffffff83251c63>] gsmld_close+0xc3/0x190 drivers/tty/n_gsm.c:2335 [<ffffffff83239a19>] tty_ldisc_close.isra.2+0x99/0xe0 drivers/tty/tty_ldisc.c:487 [<ffffffff83239aab>] tty_ldisc_kill+0x4b/0xc0 drivers/tty/tty_ldisc.c:619 [<ffffffff8323afb3>] tty_ldisc_release+0x1b3/0x260 drivers/tty/tty_ldisc.c:787 [<ffffffff83222e41>] tty_release+0xad1/0x1310 drivers/tty/tty_io.c:1904 [<ffffffff81868bbc>] __fput+0x28c/0x780 fs/file_table.c:208 [<ffffffff81869135>] ____fput+0x15/0x20 fs/file_table.c:244 [<ffffffff813ebf63>] task_work_run+0xf3/0x170 [< inline >] exit_task_work include/linux/task_work.h:21 [<ffffffff81394218>] do_exit+0x868/0x2e70 kernel/exit.c:828 [<ffffffff81396998>] do_group_exit+0x108/0x330 kernel/exit.c:958 [<ffffffff813ba4aa>] get_signal+0x62a/0x15d0 kernel/signal.c:2307 [<ffffffff81202333>] do_signal+0x83/0x1f60 arch/x86/kernel/signal.c:805 [<ffffffff81006345>] exit_to_usermode_loop+0x1a5/0x210 arch/x86/entry/common.c:163 [< inline >] prepare_exit_to_usermode arch/x86/entry/common.c:198 [<ffffffff8100869f>] syscall_return_slowpath+0x2bf/0x340 arch/x86/entry/common.c:267 [<ffffffff86e1079c>] entry_SYSCALL_64_fastpath+0xbf/0xc1 } ... key at: [<ffffffff8aef5fe0>] __key.52018+0x0/0x40 ... acquired at: [< inline >] print_irq_inversion_bug kernel/locking/lockdep.c:149 [<ffffffff81497e0b>] check_usage_forwards+0x2bb/0x2e0 kernel/locking/lockdep.c:2494 [< inline >] mark_lock_irq kernel/locking/lockdep.c:2607 [<ffffffff81499c82>] mark_lock+0x8e2/0xe80 kernel/locking/lockdep.c:3062 [< inline >] mark_irqflags kernel/locking/lockdep.c:2920 [<ffffffff8149bd74>] __lock_acquire+0xbe4/0x3410 kernel/locking/lockdep.c:3292 [<ffffffff8149f1eb>] lock_acquire+0x1db/0x450 kernel/locking/lockdep.c:3746 [< inline >] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:112 [<ffffffff86e1030f>] _raw_spin_lock_irqsave+0x9f/0xd0 kernel/locking/spinlock.c:159 [<ffffffff8324c2d6>] gsm_control_retransmit+0x26/0x220 drivers/tty/n_gsm.c:1334 [<ffffffff814fbe9e>] call_timer_fn+0x16e/0x6d0 kernel/time/timer.c:1298 [< inline >] expire_timers kernel/time/timer.c:1338 [< inline >] __run_timers kernel/time/timer.c:1627 [<ffffffff814fca46>] run_timer_softirq+0x646/0x1590 kernel/time/timer.c:1640 [<ffffffff86e1380c>] __do_softirq+0x25c/0xa3e kernel/softirq.c:273 [< inline >] invoke_softirq kernel/softirq.c:350 [<ffffffff8139b4cf>] irq_exit+0x18f/0x1d0 kernel/softirq.c:391 [< inline >] exiting_irq arch/x86/include/asm/apic.h:659 [<ffffffff86e1305b>] smp_apic_timer_interrupt+0x7b/0xa0 arch/x86/kernel/apic/apic.c:958 [<ffffffff86e1210c>] apic_timer_interrupt+0x8c/0xa0 arch/x86/entry/entry_64.S:487 [< inline >] arch_safe_halt arch/x86/include/asm/paravirt.h:107 [<ffffffff8121dcf2>] default_idle+0x52/0x370 arch/x86/kernel/process.c:308 [<ffffffff8121f36a>] arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:299 [<ffffffff8147bfd8>] default_idle_call+0x48/0xa0 kernel/sched/idle.c:93 [< inline >] cpuidle_idle_call kernel/sched/idle.c:151 [< inline >] cpu_idle_loop kernel/sched/idle.c:244 [<ffffffff8147c5c2>] cpu_startup_entry+0x592/0x7b0 kernel/sched/idle.c:293 [<ffffffff81269c2a>] start_secondary+0x2fa/0x410 arch/x86/kernel/smpboot.c:263 stack backtrace: CPU: 1 PID: 0 Comm: swapper/1 Tainted: G W 4.8.0-rc3-next-20160825+ #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 ffffffff886b6fe0 ffff88003ed078c8 ffffffff82db38d9 ffffffff00000000 fffffbfff10d6dfc ffffffff8a425720 ffff88003ed079a0 ffffffff8a0e0800 ffff88003ed079b0 ffffffff8a03b8c0 ffff88003ed07920 ffffffff816d0428 Call Trace: <IRQ> [< inline >] __dump_stack lib/dump_stack.c:15 <IRQ> [<ffffffff82db38d9>] dump_stack+0x12e/0x185 lib/dump_stack.c:51 [<ffffffff816d0428>] print_irq_inversion_bug.part.41+0x348/0x357 kernel/locking/lockdep.c:2469 [< inline >] print_irq_inversion_bug kernel/locking/lockdep.c:149 [<ffffffff81497e0b>] check_usage_forwards+0x2bb/0x2e0 kernel/locking/lockdep.c:2494 [< inline >] mark_lock_irq kernel/locking/lockdep.c:2607 [<ffffffff81499c82>] mark_lock+0x8e2/0xe80 kernel/locking/lockdep.c:3062 [< inline >] mark_irqflags kernel/locking/lockdep.c:2920 [<ffffffff8149bd74>] __lock_acquire+0xbe4/0x3410 kernel/locking/lockdep.c:3292 [<ffffffff8149f1eb>] lock_acquire+0x1db/0x450 kernel/locking/lockdep.c:3746 [< inline >] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:112 [<ffffffff86e1030f>] _raw_spin_lock_irqsave+0x9f/0xd0 kernel/locking/spinlock.c:159 [<ffffffff8324c2d6>] gsm_control_retransmit+0x26/0x220 drivers/tty/n_gsm.c:1334 [<ffffffff814fbe9e>] call_timer_fn+0x16e/0x6d0 kernel/time/timer.c:1298 [< inline >] expire_timers kernel/time/timer.c:1338 [< inline >] __run_timers kernel/time/timer.c:1627 [<ffffffff814fca46>] run_timer_softirq+0x646/0x1590 kernel/time/timer.c:1640 [<ffffffff86e1380c>] __do_softirq+0x25c/0xa3e kernel/softirq.c:273 [< inline >] invoke_softirq kernel/softirq.c:350 [<ffffffff8139b4cf>] irq_exit+0x18f/0x1d0 kernel/softirq.c:391 [< inline >] exiting_irq arch/x86/include/asm/apic.h:659 [<ffffffff86e1305b>] smp_apic_timer_interrupt+0x7b/0xa0 arch/x86/kernel/apic/apic.c:958 [<ffffffff86e1210c>] apic_timer_interrupt+0x8c/0xa0 arch/x86/entry/entry_64.S:487 <EOI> [<ffffffff8128f716>] ? native_safe_halt+0x6/0x10 [< inline >] arch_safe_halt arch/x86/include/asm/paravirt.h:107 [<ffffffff8121dcf2>] default_idle+0x52/0x370 arch/x86/kernel/process.c:308 [<ffffffff8121f36a>] arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:299 [<ffffffff8147bfd8>] default_idle_call+0x48/0xa0 kernel/sched/idle.c:93 [< inline >] cpuidle_idle_call kernel/sched/idle.c:151 [< inline >] cpu_idle_loop kernel/sched/idle.c:244 [<ffffffff8147c5c2>] cpu_startup_entry+0x592/0x7b0 kernel/sched/idle.c:293 [<ffffffff81269c2a>] start_secondary+0x2fa/0x410 arch/x86/kernel/smpboot.c:263 sr 1:0:0:0: [sr0] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE sr 1:0:0:0: [sr0] tag#0 Sense Key : Not Ready [current] sr 1:0:0:0: [sr0] tag#0 Add. Sense: Medium not present sr 1:0:0:0: [sr0] tag#0 CDB: Read(10) 28 00 00 00 00 00 00 00 08 00 blk_update_request: I/O error, dev sr0, sector 0 sr 1:0:0:0: [sr0] tag#0 unaligned transfer