INFO: task systemd-udevd:27325 blocked for more than 143 seconds. Not tainted 5.7.0-rc6-next-20200522-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D26992 27325 3916 0x00000100 Call Trace: context_switch kernel/sched/core.c:3415 [inline] __schedule+0x8e4/0x1f80 kernel/sched/core.c:4140 firmware_map_remove+0x19e/0x19e schedule+0xd0/0x2a0 kernel/sched/core.c:4215 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4274 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 __blkdev_get+0x179/0x1530 fs/block_dev.c:1582 mutex_trylock+0x2c0/0x2c0 kernel/locking/mutex.c:126 set_irq_regs arch/x86/include/asm/irq_regs.h:27 [inline] smp_apic_timer_interrupt+0x1b6/0x600 arch/x86/kernel/apic/apic.c:1109 disk_block_events+0x1d/0x130 block/genhd.c:1885 disk_block_events+0x3f/0x130 block/genhd.c:1885 __blkdev_get+0x179/0x1530 fs/block_dev.c:1582 __blkdev_get+0x179/0x1530 fs/block_dev.c:1582 find_held_lock+0x2d/0x110 kernel/locking/lockdep.c:4483 __blkdev_put+0x6f0/0x6f0 fs/block_dev.c:1916 instrument_atomic_write include/linux/instrumented.h:71 [inline] atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:695 [inline] queued_spin_lock include/asm-generic/qspinlock.h:78 [inline] do_raw_spin_lock+0x129/0x2e0 kernel/locking/spinlock_debug.c:113 rwlock_bug.part.0+0x90/0x90 include/linux/sched.h:1359 blkdev_get+0x41/0x2b0 fs/block_dev.c:1730 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 blkdev_open+0x21d/0x2b0 fs/block_dev.c:1869 do_dentry_open+0x503/0x1280 fs/open.c:822 bd_acquire+0x2c0/0x2c0 fs/block_dev.c:923 chown_common+0x550/0x550 fs/open.c:661 inode_permission+0xab/0x500 fs/namei.c:450 do_open fs/namei.c:3234 [inline] path_openat+0x1ece/0x2870 fs/namei.c:3351 path_lookupat.isra.0+0x530/0x530 fs/namei.c:2332 do_filp_open+0x192/0x260 fs/namei.c:3378 may_open_dev+0xf0/0xf0 fs/namei.c:2821 instrument_atomic_write include/linux/instrumented.h:71 [inline] atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:695 [inline] queued_spin_lock include/asm-generic/qspinlock.h:78 [inline] do_raw_spin_lock+0x129/0x2e0 kernel/locking/spinlock_debug.c:113 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:393 [inline] __alloc_fd+0x46d/0x600 fs/file.c:534 do_sys_openat2+0x585/0x7a0 fs/open.c:1173 file_open_root+0x400/0x400 fs/open.c:1154 __secure_computing+0x104/0x360 kernel/seccomp.c:950 syscall_trace_enter+0x41d/0xd10 arch/x86/entry/common.c:130 do_sys_open+0xc3/0x140 fs/open.c:1189 filp_open+0x70/0x70 fs/open.c:1142 do_syscall_64+0x21/0x7d0 arch/x86/entry/common.c:288 __trace_hardirqs_on_caller kernel/locking/lockdep.c:3635 [inline] lockdep_hardirqs_on_prepare+0x3a2/0x590 kernel/locking/lockdep.c:3686 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.2:28343 can't die for more than 143 seconds. syz-executor.2 D24904 28343 7030 0x00004004 Call Trace: context_switch kernel/sched/core.c:3415 [inline] __schedule+0x8e4/0x1f80 kernel/sched/core.c:4140 trace_hardirqs_on_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:41 firmware_map_remove+0x19e/0x19e retint_kernel+0x2b/0x2b schedule+0xd0/0x2a0 kernel/sched/core.c:4215 io_schedule+0x17/0x60 kernel/sched/core.c:5858 wait_on_page_bit_common+0x351/0xdb0 mm/filemap.c:1150 replace_page_cache_page+0x17d0/0x17d0 include/linux/memcontrol.h:419 block_truncate_page+0xc50/0xc50 arch/x86/include/asm/bitops.h:211 page_cache_next_miss+0x300/0x300 mm/filemap.c:1448 read_mems_allowed_retry include/linux/cpuset.h:146 [inline] __page_cache_alloc mm/filemap.c:952 [inline] __page_cache_alloc+0x110/0x480 mm/filemap.c:941 wait_on_page_bit mm/filemap.c:1199 [inline] wait_on_page_locked include/linux/pagemap.h:568 [inline] wait_on_page_read mm/filemap.c:2735 [inline] do_read_cache_page+0xf95/0x1810 mm/filemap.c:2778 string_nocheck+0x1a9/0x220 lib/vsprintf.c:616 generic_file_read_iter+0x2200/0x2200 include/linux/pagemap.h:259 instrument_atomic_read include/linux/instrumented.h:56 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline] hlock_class kernel/locking/lockdep.c:179 [inline] mark_lock+0x11f/0xdd0 kernel/locking/lockdep.c:3937 format_decode+0x230/0xad0 lib/vsprintf.c:2372 print_usage_bug+0x240/0x240 kernel/locking/lockdep.c:101 enable_ptr_key_workfn+0x30/0x30 lib/vsprintf.c:725 hex_string+0x4c0/0x4c0 lib/vsprintf.c:1159 read_mapping_page include/linux/pagemap.h:437 [inline] read_part_sector+0xf6/0x600 block/partitions/core.c:771 adfspart_check_ADFS+0x7f0/0x7f0 include/linux/mm.h:1079 adfspart_check_ICS+0x9d/0xc80 block/partitions/acorn.c:360 adfspart_check_ADFS+0x7f0/0x7f0 include/linux/mm.h:1079 retint_kernel+0x2b/0x2b memset include/linux/string.h:391 [inline] check_partition block/partitions/core.c:139 [inline] blk_add_partitions+0x46e/0xe40 block/partitions/core.c:699 memory_is_nonzero mm/kasan/generic.c:120 [inline] memory_is_poisoned_n mm/kasan/generic.c:134 [inline] memory_is_poisoned mm/kasan/generic.c:165 [inline] check_memory_region_inline mm/kasan/generic.c:183 [inline] check_memory_region+0xa1/0x190 mm/kasan/generic.c:192 adfspart_check_ADFS+0x7f0/0x7f0 include/linux/mm.h:1079 check_partition block/partitions/core.c:140 [inline] blk_add_partitions+0x474/0xe40 block/partitions/core.c:699 bdev_disk_changed+0x1fb/0x380 fs/block_dev.c:1525 __blkdev_get+0x130c/0x1530 fs/block_dev.c:1663 find_held_lock+0x2d/0x110 kernel/locking/lockdep.c:4483 __blkdev_put+0x6f0/0x6f0 fs/block_dev.c:1916 instrument_atomic_write include/linux/instrumented.h:71 [inline] atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:695 [inline] queued_spin_lock include/asm-generic/qspinlock.h:78 [inline] do_raw_spin_lock+0x129/0x2e0 kernel/locking/spinlock_debug.c:113 rwlock_bug.part.0+0x90/0x90 include/linux/sched.h:1359 blkdev_get+0x41/0x2b0 fs/block_dev.c:1730 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 blkdev_open+0x21d/0x2b0 fs/block_dev.c:1869 do_dentry_open+0x503/0x1280 fs/open.c:822 bd_acquire+0x2c0/0x2c0 fs/block_dev.c:923 chown_common+0x550/0x550 fs/open.c:661 inode_permission+0xab/0x500 fs/namei.c:450 do_open fs/namei.c:3234 [inline] path_openat+0x1ece/0x2870 fs/namei.c:3351 path_lookupat.isra.0+0x530/0x530 fs/namei.c:2332 mark_held_locks+0x9f/0xe0 kernel/locking/lockdep.c:3609 trace_hardirqs_on_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:41 do_filp_open+0x192/0x260 fs/namei.c:3378 may_open_dev+0xf0/0xf0 fs/namei.c:2821 _find_next_bit.constprop.0+0x3d/0x200 lib/find_bit.c:39 _find_next_bit.constprop.0+0x66/0x200 lib/find_bit.c:39 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:393 [inline] __alloc_fd+0x46d/0x600 fs/file.c:534 do_sys_openat2+0x585/0x7a0 fs/open.c:1173 file_open_root+0x400/0x400 fs/open.c:1154 trace_hardirqs_on_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:41 do_sys_open+0xc3/0x140 fs/open.c:1189 filp_open+0x70/0x70 fs/open.c:1142 arch_local_irq_enable arch/x86/include/asm/paravirt.h:775 [inline] do_syscall_64+0x4f/0x7d0 arch/x86/entry/common.c:288 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.2:28343 blocked for more than 143 seconds. Not tainted 5.7.0-rc6-next-20200522-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D24904 28343 7030 0x00004004 Call Trace: context_switch kernel/sched/core.c:3415 [inline] __schedule+0x8e4/0x1f80 kernel/sched/core.c:4140 trace_hardirqs_on_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:41 firmware_map_remove+0x19e/0x19e retint_kernel+0x2b/0x2b schedule+0xd0/0x2a0 kernel/sched/core.c:4215 io_schedule+0x17/0x60 kernel/sched/core.c:5858 wait_on_page_bit_common+0x351/0xdb0 mm/filemap.c:1150 replace_page_cache_page+0x17d0/0x17d0 include/linux/memcontrol.h:419 block_truncate_page+0xc50/0xc50 arch/x86/include/asm/bitops.h:211 page_cache_next_miss+0x300/0x300 mm/filemap.c:1448 read_mems_allowed_retry include/linux/cpuset.h:146 [inline] __page_cache_alloc mm/filemap.c:952 [inline] __page_cache_alloc+0x110/0x480 mm/filemap.c:941 wait_on_page_bit mm/filemap.c:1199 [inline] wait_on_page_locked include/linux/pagemap.h:568 [inline] wait_on_page_read mm/filemap.c:2735 [inline] do_read_cache_page+0xf95/0x1810 mm/filemap.c:2778 string_nocheck+0x1a9/0x220 lib/vsprintf.c:616 generic_file_read_iter+0x2200/0x2200 include/linux/pagemap.h:259 instrument_atomic_read include/linux/instrumented.h:56 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline] hlock_class kernel/locking/lockdep.c:179 [inline] mark_lock+0x11f/0xdd0 kernel/locking/lockdep.c:3937 format_decode+0x230/0xad0 lib/vsprintf.c:2372 print_usage_bug+0x240/0x240 kernel/locking/lockdep.c:101 enable_ptr_key_workfn+0x30/0x30 lib/vsprintf.c:725 hex_string+0x4c0/0x4c0 lib/vsprintf.c:1159 read_mapping_page include/linux/pagemap.h:437 [inline] read_part_sector+0xf6/0x600 block/partitions/core.c:771 adfspart_check_ADFS+0x7f0/0x7f0 include/linux/mm.h:1079 adfspart_check_ICS+0x9d/0xc80 block/partitions/acorn.c:360 adfspart_check_ADFS+0x7f0/0x7f0 include/linux/mm.h:1079 retint_kernel+0x2b/0x2b memset include/linux/string.h:391 [inline] check_partition block/partitions/core.c:139 [inline] blk_add_partitions+0x46e/0xe40 block/partitions/core.c:699 memory_is_nonzero mm/kasan/generic.c:120 [inline] memory_is_poisoned_n mm/kasan/generic.c:134 [inline] memory_is_poisoned mm/kasan/generic.c:165 [inline] check_memory_region_inline mm/kasan/generic.c:183 [inline] check_memory_region+0xa1/0x190 mm/kasan/generic.c:192 adfspart_check_ADFS+0x7f0/0x7f0 include/linux/mm.h:1079 check_partition block/partitions/core.c:140 [inline] blk_add_partitions+0x474/0xe40 block/partitions/core.c:699 bdev_disk_changed+0x1fb/0x380 fs/block_dev.c:1525 __blkdev_get+0x130c/0x1530 fs/block_dev.c:1663 find_held_lock+0x2d/0x110 kernel/locking/lockdep.c:4483 __blkdev_put+0x6f0/0x6f0 fs/block_dev.c:1916 instrument_atomic_write include/linux/instrumented.h:71 [inline] atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:695 [inline] queued_spin_lock include/asm-generic/qspinlock.h:78 [inline] do_raw_spin_lock+0x129/0x2e0 kernel/locking/spinlock_debug.c:113 rwlock_bug.part.0+0x90/0x90 include/linux/sched.h:1359 blkdev_get+0x41/0x2b0 fs/block_dev.c:1730 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 blkdev_open+0x21d/0x2b0 fs/block_dev.c:1869 do_dentry_open+0x503/0x1280 fs/open.c:822 bd_acquire+0x2c0/0x2c0 fs/block_dev.c:923 chown_common+0x550/0x550 fs/open.c:661 inode_permission+0xab/0x500 fs/namei.c:450 do_open fs/namei.c:3234 [inline] path_openat+0x1ece/0x2870 fs/namei.c:3351 path_lookupat.isra.0+0x530/0x530 fs/namei.c:2332 mark_held_locks+0x9f/0xe0 kernel/locking/lockdep.c:3609 trace_hardirqs_on_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:41 do_filp_open+0x192/0x260 fs/namei.c:3378 may_open_dev+0xf0/0xf0 fs/namei.c:2821 _find_next_bit.constprop.0+0x3d/0x200 lib/find_bit.c:39 _find_next_bit.constprop.0+0x66/0x200 lib/find_bit.c:39 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:393 [inline] __alloc_fd+0x46d/0x600 fs/file.c:534 do_sys_openat2+0x585/0x7a0 fs/open.c:1173 file_open_root+0x400/0x400 fs/open.c:1154 trace_hardirqs_on_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:41 do_sys_open+0xc3/0x140 fs/open.c:1189 filp_open+0x70/0x70 fs/open.c:1142 arch_local_irq_enable arch/x86/include/asm/paravirt.h:775 [inline] do_syscall_64+0x4f/0x7d0 arch/x86/entry/common.c:288 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.2:28348 can't die for more than 144 seconds. syz-executor.2 D28592 28348 7030 0x00004006 Call Trace: context_switch kernel/sched/core.c:3415 [inline] __schedule+0x8e4/0x1f80 kernel/sched/core.c:4140 firmware_map_remove+0x19e/0x19e schedule+0xd0/0x2a0 kernel/sched/core.c:4215 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4274 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 blkdev_put+0x30/0x520 fs/block_dev.c:1920 mutex_trylock+0x2c0/0x2c0 kernel/locking/mutex.c:126 lock_downgrade+0x840/0x840 kernel/locking/lockdep.c:4604 instrument_atomic_write include/linux/instrumented.h:71 [inline] atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:695 [inline] queued_spin_lock include/asm-generic/qspinlock.h:78 [inline] do_raw_spin_lock+0x129/0x2e0 kernel/locking/spinlock_debug.c:113 rwlock_bug.part.0+0x90/0x90 include/linux/sched.h:1359 locks_check_ctx_file_list+0x1d/0x110 fs/locks.c:312 pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:656 [inline] queued_spin_unlock arch/x86/include/asm/qspinlock.h:55 [inline] do_raw_spin_unlock+0x171/0x260 kernel/locking/spinlock_debug.c:139 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:393 [inline] locks_remove_file+0x329/0x590 fs/locks.c:2797 blkdev_put+0x520/0x520 fs/block_dev.c:1939 blkdev_put+0x30/0x520 fs/block_dev.c:1920 blkdev_put+0x30/0x520 fs/block_dev.c:1920 blkdev_put+0x520/0x520 fs/block_dev.c:1939 blkdev_close+0x8c/0xb0 fs/block_dev.c:1969 __fput+0x33e/0x880 fs/file_table.c:281 task_work_run+0xf4/0x1b0 kernel/task_work.c:123 get_signal+0x207a/0x2510 kernel/signal.c:2533 nbd_release+0x150/0x150 drivers/block/nbd.c:1506 __sanitizer_cov_trace_switch+0x45/0x70 kernel/kcov.c:320 do_signal+0x81/0x2240 arch/x86/kernel/signal.c:810 ioctl_file_clone+0x180/0x180 fs/ioctl.c:237 copy_siginfo_to_user32+0xa0/0xa0 include/linux/sched/task_stack.h:21 blkdev_ioctl+0xc9/0x6c0 block/ioctl.c:613 blkdev_common_ioctl+0x1770/0x1770 block/ioctl.c:541 do_dup2+0x520/0x520 fs/file.c:236 check_preemption_disabled lib/smp_processor_id.c:52 [inline] debug_smp_processor_id+0x2f/0x185 lib/smp_processor_id.c:57 kick_process+0xe4/0x170 kernel/sched/core.c:1993 task_work_add+0x97/0x120 kernel/task_work.c:35 exit_to_usermode_loop+0x36/0x360 arch/x86/entry/common.c:148 __trace_hardirqs_on_caller kernel/locking/lockdep.c:3635 [inline] lockdep_hardirqs_on_prepare+0x3a2/0x590 kernel/locking/lockdep.c:3686 exit_to_usermode_loop+0x26c/0x360 arch/x86/entry/common.c:161 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.2:28348 blocked for more than 144 seconds. Not tainted 5.7.0-rc6-next-20200522-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28592 28348 7030 0x00004006 Call Trace: context_switch kernel/sched/core.c:3415 [inline] __schedule+0x8e4/0x1f80 kernel/sched/core.c:4140 firmware_map_remove+0x19e/0x19e schedule+0xd0/0x2a0 kernel/sched/core.c:4215 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4274 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 blkdev_put+0x30/0x520 fs/block_dev.c:1920 mutex_trylock+0x2c0/0x2c0 kernel/locking/mutex.c:126 lock_downgrade+0x840/0x840 kernel/locking/lockdep.c:4604 instrument_atomic_write include/linux/instrumented.h:71 [inline] atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:695 [inline] queued_spin_lock include/asm-generic/qspinlock.h:78 [inline] do_raw_spin_lock+0x129/0x2e0 kernel/locking/spinlock_debug.c:113 rwlock_bug.part.0+0x90/0x90 include/linux/sched.h:1359 locks_check_ctx_file_list+0x1d/0x110 fs/locks.c:312 pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:656 [inline] queued_spin_unlock arch/x86/include/asm/qspinlock.h:55 [inline] do_raw_spin_unlock+0x171/0x260 kernel/locking/spinlock_debug.c:139 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:393 [inline] locks_remove_file+0x329/0x590 fs/locks.c:2797 blkdev_put+0x520/0x520 fs/block_dev.c:1939 blkdev_put+0x30/0x520 fs/block_dev.c:1920 blkdev_put+0x30/0x520 fs/block_dev.c:1920 blkdev_put+0x520/0x520 fs/block_dev.c:1939 blkdev_close+0x8c/0xb0 fs/block_dev.c:1969 __fput+0x33e/0x880 fs/file_table.c:281 task_work_run+0xf4/0x1b0 kernel/task_work.c:123 get_signal+0x207a/0x2510 kernel/signal.c:2533 nbd_release+0x150/0x150 drivers/block/nbd.c:1506 __sanitizer_cov_trace_switch+0x45/0x70 kernel/kcov.c:320 do_signal+0x81/0x2240 arch/x86/kernel/signal.c:810 ioctl_file_clone+0x180/0x180 fs/ioctl.c:237 copy_siginfo_to_user32+0xa0/0xa0 include/linux/sched/task_stack.h:21 blkdev_ioctl+0xc9/0x6c0 block/ioctl.c:613 blkdev_common_ioctl+0x1770/0x1770 block/ioctl.c:541 do_dup2+0x520/0x520 fs/file.c:236 check_preemption_disabled lib/smp_processor_id.c:52 [inline] debug_smp_processor_id+0x2f/0x185 lib/smp_processor_id.c:57 kick_process+0xe4/0x170 kernel/sched/core.c:1993 task_work_add+0x97/0x120 kernel/task_work.c:35 exit_to_usermode_loop+0x36/0x360 arch/x86/entry/common.c:148 __trace_hardirqs_on_caller kernel/locking/lockdep.c:3635 [inline] lockdep_hardirqs_on_prepare+0x3a2/0x590 kernel/locking/lockdep.c:3686 exit_to_usermode_loop+0x26c/0x360 arch/x86/entry/common.c:161 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Showing all locks held in the system: 1 lock held by khungtaskd/1149: #0: ffffffff89bc0380 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779 1 lock held by in:imklog/6655: 2 locks held by agetty/6763: #0: ffff88809f142098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc90000ff02e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x220/0x1b30 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.2/21282: #0: ffff88808a5bd380 (&bdev->bd_mutex){+.+.}-{3:3}, at: blkdev_put+0x30/0x520 fs/block_dev.c:1920 1 lock held by syz-executor.2/21309: #0: ffff88808a5bd380 (&bdev->bd_mutex){+.+.}-{3:3}, at: blkdev_put+0x30/0x520 fs/block_dev.c:1920 1 lock held by syz-executor.2/21348: #0: ffff88808a5bd380 (&bdev->bd_mutex){+.+.}-{3:3}, at: blkdev_put+0x30/0x520 fs/block_dev.c:1920 1 lock held by syz-executor.2/21366: #0: ffff88808a5bd380 (&bdev->bd_mutex){+.+.}-{3:3}, at: blkdev_put+0x30/0x520 fs/block_dev.c:1920 1 lock held by syz-executor.2/21398: #0: ffff88808a5bd380 (&bdev->bd_mutex){+.+.}-{3:3}, at: blkdev_put+0x30/0x520 fs/block_dev.c:1920 1 lock held by syz-executor.2/21440: #0: ffff88808a5bd380 (&bdev->bd_mutex){+.+.}-{3:3}, at: blkdev_put+0x30/0x520 fs/block_dev.c:1920 1 lock held by syz-executor.2/21458: #0: ffff88808a5bd380 (&bdev->bd_mutex){+.+.}-{3:3}, at: blkdev_put+0x30/0x520 fs/block_dev.c:1920 1 lock held by systemd-udevd/27325: #0: ffff88808a5bd380 (&bdev->bd_mutex){+.+.}-{3:3}, at: __blkdev_get+0x179/0x1530 fs/block_dev.c:1582 1 lock held by syz-executor.2/28343: #0: ffff88808a5bd380 (&bdev->bd_mutex){+.+.}-{3:3}, at: __blkdev_get+0x179/0x1530 fs/block_dev.c:1582 1 lock held by syz-executor.2/28348: #0: ffff88808a5bd380 (&bdev->bd_mutex){+.+.}-{3:3}, at: blkdev_put+0x30/0x520 fs/block_dev.c:1920 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1149 Comm: khungtaskd Not tainted 5.7.0-rc6-next-20200522-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 lapic_can_unplug_cpu.cold+0x3b/0x3b nmi_trigger_cpumask_backtrace+0x1e6/0x221 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline] watchdog+0xfa3/0x14f0 kernel/hung_task.c:339 reset_hung_task_detector+0x30/0x30 kernel/hung_task.c:293 kthread+0x3b5/0x4a0 kernel/kthread.c:291 kthread_mod_delayed_work+0x1a0/0x1a0 kernel/kthread.c:1113 kthread_mod_delayed_work+0x1a0/0x1a0 kernel/kthread.c:1113 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3907 Comm: systemd-journal Not tainted 5.7.0-rc6-next-20200522-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0033:0x7f7ef27a3dca Code: 50 40 49 c7 47 48 00 00 00 00 49 c7 47 40 00 00 00 00 49 8b 04 24 4c 3b 78 68 0f 84 1b 04 00 00 41 80 67 08 fb 4d 89 7c 24 10 <49> 8b 47 50 48 85 c0 49 89 44 24 18 74 04 4c 89 60 20 49 c7 44 24 RSP: 002b:00007ffd98ab54b0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000119fd8 RCX: 0000000000119fd8 RDX: 0000000000800000 RSI: 0000000000000001 RDI: 0000560cecc353c0 RBP: 0000560cecc31040 R08: 0000000000119fe8 R09: 0000560cecc34da0 R10: 784396f30de3c684 R11: c9e14cae12d356f2 R12: 0000560cecc353c0 R13: 0000000000000003 R14: 0000000000000010 R15: 0000560cecc35120 FS: 00007f7ef2b6a8c0 GS: 0000000000000000