INFO: task syz-executor4:2494 blocked for more than 140 seconds. Not tainted 4.18.0+ #190 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D24576 2494 4498 0x00000004 Call Trace: context_switch kernel/sched/core.c:2823 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3471 schedule+0xfb/0x450 kernel/sched/core.c:3515 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3573 __mutex_lock_common kernel/locking/mutex.c:834 [inline] __mutex_lock+0xee2/0x18a0 kernel/locking/mutex.c:894 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:909 blkdev_put+0x34/0x540 fs/block_dev.c:1816 blkdev_close+0x8b/0xb0 fs/block_dev.c:1865 __fput+0x39b/0x860 fs/file_table.c:251 ____fput+0x15/0x20 fs/file_table.c:282 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x410c41 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 34 19 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffcf11ecf60 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000410c41 RDX: 0000000000000000 RSI: 0000000000730380 RDI: 0000000000000004 RBP: 0000000000000000 R08: ffffffffffffffff R09: ffffffffffffffff R10: 00007ffcf11ece90 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000075c47 R14: 00000000000001da R15: badc0ffeebadface INFO: task syz-executor4:2515 blocked for more than 140 seconds. Not tainted 4.18.0+ #190 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D24280 2515 4498 0x00000004 Call Trace: context_switch kernel/sched/core.c:2823 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3471 schedule+0xfb/0x450 kernel/sched/core.c:3515 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3573 __mutex_lock_common kernel/locking/mutex.c:834 [inline] __mutex_lock+0xee2/0x18a0 kernel/locking/mutex.c:894 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:909 __blkdev_get+0x19b/0x13c0 fs/block_dev.c:1466 blkdev_get+0xc1/0xb50 fs/block_dev.c:1617 blkdev_open+0x1fb/0x280 fs/block_dev.c:1775 do_dentry_open+0x4d5/0x1190 fs/open.c:782 vfs_open+0x12f/0x220 fs/open.c:896 do_last fs/namei.c:3371 [inline] path_openat+0x1076/0x4c90 fs/namei.c:3487 do_filp_open+0x255/0x380 fs/namei.c:3517 do_sys_open+0x584/0x760 fs/open.c:1061 __do_sys_open fs/open.c:1079 [inline] __se_sys_open fs/open.c:1074 [inline] __x64_sys_open+0x7e/0xc0 fs/open.c:1074 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x410dc1 Code: 75 14 b8 02 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 b4 17 00 00 c3 48 83 ec 08 e8 8a fa ff ff 48 89 04 24 b8 02 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 d3 fa ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007fd56c699a80 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00000000200001e8 RCX: 0000000000410dc1 RDX: 00007fd56c699afa RSI: 0000000000000002 RDI: 00007fd56c699af0 RBP: 0000000000000001 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000293 R12: 0000000000000005 R13: 0000000000000001 R14: 00000000004c9d2d R15: 0000000000000001 INFO: task syz-executor6:2511 blocked for more than 140 seconds. Not tainted 4.18.0+ #190 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor6 D24568 2511 4500 0x00000004 Call Trace: context_switch kernel/sched/core.c:2823 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3471 schedule+0xfb/0x450 kernel/sched/core.c:3515 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline] rwsem_down_read_failed+0x362/0x610 kernel/locking/rwsem-xadd.c:286 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0xc3/0x1d0 kernel/locking/rwsem.c:26 __get_super.part.12+0x20f/0x2e0 fs/super.c:695 __get_super include/linux/spinlock.h:329 [inline] get_super+0x2d/0x50 fs/super.c:724 fsync_bdev+0x17/0xc0 fs/block_dev.c:469 invalidate_partition+0x35/0x60 block/genhd.c:1561 drop_partitions.isra.13+0xe8/0x200 block/partition-generic.c:445 rescan_partitions+0x75/0x910 block/partition-generic.c:518 __blkdev_reread_part+0x1ad/0x230 block/ioctl.c:173 blkdev_reread_part+0x26/0x40 block/ioctl.c:193 loop_reread_partitions+0x163/0x190 drivers/block/loop.c:645 loop_set_status+0xb95/0x1010 drivers/block/loop.c:1199 loop_set_status64+0xaa/0x100 drivers/block/loop.c:1317 lo_ioctl+0x90e/0x1d90 drivers/block/loop.c:1433 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x9cd/0x2030 block/ioctl.c:601 block_ioctl+0xee/0x130 fs/block_dev.c:1883 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:684 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701 __do_sys_ioctl fs/ioctl.c:708 [inline] __se_sys_ioctl fs/ioctl.c:706 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:706 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457089 Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2131bb9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f2131bba6d4 RCX: 0000000000457089 RDX: 00000000200000c0 RSI: 0000000000004c04 RDI: 0000000000000003 RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004cf300 R14: 00000000004c5908 R15: 0000000000000000 INFO: task syz-executor6:2526 blocked for more than 140 seconds. Not tainted 4.18.0+ #190 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor6 D24280 2526 4500 0x00000004 Call Trace: context_switch kernel/sched/core.c:2823 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3471 schedule+0xfb/0x450 kernel/sched/core.c:3515 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3573 __mutex_lock_common kernel/locking/mutex.c:834 [inline] __mutex_lock+0xee2/0x18a0 kernel/locking/mutex.c:894 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:909 __blkdev_get+0x19b/0x13c0 fs/block_dev.c:1466 blkdev_get+0xc1/0xb50 fs/block_dev.c:1617 blkdev_open+0x1fb/0x280 fs/block_dev.c:1775 do_dentry_open+0x4d5/0x1190 fs/open.c:782 vfs_open+0x12f/0x220 fs/open.c:896 do_last fs/namei.c:3371 [inline] path_openat+0x1076/0x4c90 fs/namei.c:3487 do_filp_open+0x255/0x380 fs/namei.c:3517 do_sys_open+0x584/0x760 fs/open.c:1061 __do_sys_open fs/open.c:1079 [inline] __se_sys_open fs/open.c:1074 [inline] __x64_sys_open+0x7e/0xc0 fs/open.c:1074 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x410dc1 Code: 75 14 b8 02 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 b4 17 00 00 c3 48 83 ec 08 e8 8a fa ff ff 48 89 04 24 b8 02 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 d3 fa ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007f2131b777a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000410dc1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007f2131b77850 RBP: 00000000009301e0 R08: 000000000000000f R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00000000ffffffff R13: 00000000004d68a8 R14: 00000000004c9e86 R15: 0000000000000002 Showing all locks held in the system: 1 lock held by khungtaskd/776: #0: 00000000c8fe1416 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4461 1 lock held by rsyslogd/4359: 2 locks held by getty/4449: #0: 00000000250d9473 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000002d21d17e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4450: #0: 000000001057adcf (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000005ef7f62 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4451: #0: 0000000039ad561e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000957de675 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4452: #0: 00000000ee86fade (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000681b9130 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4453: #0: 00000000d6f30578 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000045efd6bc (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4454: #0: 00000000304d74c6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000609983dc (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4455: #0: 00000000eff5284a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000a1208cd4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by kworker/0:4/18289: #0: 0000000098be4e88 ((wq_completion)"events"){+.+.}, at: __write_once_size include/linux/compiler.h:215 [inline] #0: 0000000098be4e88 ((wq_completion)"events"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 0000000098be4e88 ((wq_completion)"events"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 0000000098be4e88 ((wq_completion)"events"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 0000000098be4e88 ((wq_completion)"events"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 0000000098be4e88 ((wq_completion)"events"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 0000000098be4e88 ((wq_completion)"events"){+.+.}, at: process_one_work+0xb44/0x1ba0 kernel/workqueue.c:2124 #1: 00000000b831643f ((work_completion)(&smc->tcp_listen_work)){+.+.}, at: process_one_work+0xb9b/0x1ba0 kernel/workqueue.c:2128 1 lock held by syz-executor4/2494: #0: 00000000eaa2bf55 (&bdev->bd_mutex){+.+.}, at: blkdev_put+0x34/0x540 fs/block_dev.c:1816 1 lock held by syz-executor4/2499: 1 lock held by syz-executor4/2515: #0: 00000000eaa2bf55 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x13c0 fs/block_dev.c:1466 3 locks held by syz-executor6/2511: #0: 000000005ff91d81 (&lo->lo_ctl_mutex/1){+.+.}, at: lo_ioctl+0x8e/0x1d90 drivers/block/loop.c:1403 #1: 00000000eaa2bf55 (&bdev->bd_mutex){+.+.}, at: blkdev_reread_part+0x1e/0x40 block/ioctl.c:192 #2: 0000000040955e63 (&type->s_umount_key#46){++++}, at: __get_super.part.12+0x20f/0x2e0 fs/super.c:695 1 lock held by syz-executor6/2526: #0: 00000000eaa2bf55 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x13c0 fs/block_dev.c:1466 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 776 Comm: khungtaskd Not tainted 4.18.0+ #190 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+0x1c9/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline] watchdog+0x9c4/0xf80 kernel/hung_task.c:252 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2293 Comm: udevd Not tainted 4.18.0+ #190 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:write_comp_data+0x1/0x70 kernel/kcov.c:116 Code: ff ff 48 8b bd d0 fe ff ff e8 3b 3f 3e 00 e9 ad fc ff ff 4c 89 ef e8 8e 3e 3e 00 e9 76 fc ff ff e8 04 9b ca ff 90 90 90 90 55 <65> 4c 8b 04 25 40 ee 01 00 65 8b 05 1f 1e 85 7e 48 89 e5 a9 00 01 RSP: 0018:ffff8801ca497340 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffff8801ca755918 RCX: ffffffff81db6621 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000005 RBP: ffff8801ca497350 R08: ffff8801ca48a000 R09: ffffed00399bcc7f R10: ffffed00399bcc7f R11: ffff8801ccde63ff R12: dffffc0000000000 R13: ffff8801ca497630 R14: 0000000000000000 R15: 0000000000000001 FS: 00007f9505d227a0(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000016a7978 CR3: 00000001caa7d000 CR4: 00000000001406e0 Call Trace: ep_wakeup_source fs/eventpoll.c:622 [inline] ep_pm_stay_awake fs/eventpoll.c:628 [inline] ep_send_events_proc+0xbb1/0xf00 fs/eventpoll.c:1690 ep_scan_ready_list+0x3c5/0xf50 fs/eventpoll.c:699 ep_send_events fs/eventpoll.c:1706 [inline] ep_poll+0x3ef/0x1220 fs/eventpoll.c:1832 do_epoll_wait+0x1b0/0x200 fs/eventpoll.c:2190 __do_sys_epoll_wait fs/eventpoll.c:2200 [inline] __se_sys_epoll_wait fs/eventpoll.c:2197 [inline] __x64_sys_epoll_wait+0x97/0xf0 fs/eventpoll.c:2197 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f9505436943 Code: 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 90 90 90 90 90 90 83 3d b5 dc 2a 00 00 75 13 49 89 ca b8 e8 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 3b c4 00 00 48 89 04 24 RSP: 002b:00007ffe1456a0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8 RAX: ffffffffffffffda RBX: 0000000000000bb8 RCX: 00007f9505436943 RDX: 0000000000000008 RSI: 00007ffe1456a1e0 RDI: 000000000000000a RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000bb8 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000000 R14: 000000000203bcb0 R15: 000000000202e250