INFO: task syz-executor.0:14740 blocked for more than 143 seconds. Not tainted 5.1.0-rc4+ #67 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D26016 14740 8233 0x00000004 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:285 [inline] rwsem_down_read_failed+0x213/0x420 kernel/locking/rwsem-xadd.c:302 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+0x49/0x90 kernel/locking/rwsem.c:26 __get_super.part.0+0x203/0x2e0 fs/super.c:788 __get_super include/linux/spinlock.h:329 [inline] get_super+0x2e/0x50 fs/super.c:817 fsync_bdev+0x19/0xd0 fs/block_dev.c:525 blkdev_flushbuf block/ioctl.c:436 [inline] blkdev_ioctl+0x8f1/0x1d10 block/ioctl.c:521 block_ioctl+0xee/0x130 fs/block_dev.c:1933 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c29 Code: Bad RIP value. RSP: 002b:00007fe5319b2c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458c29 RDX: 0000000000000000 RSI: 0000000000001261 RDI: 0000000000000004 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe5319b36d4 R13: 00000000004bffd6 R14: 00000000004d2360 R15: 00000000ffffffff INFO: task syz-executor.0:14752 blocked for more than 143 seconds. Not tainted 5.1.0-rc4+ #67 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29448 14752 8233 0x00000004 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:285 [inline] rwsem_down_read_failed+0x213/0x420 kernel/locking/rwsem-xadd.c:302 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+0x49/0x90 kernel/locking/rwsem.c:26 __get_super.part.0+0x203/0x2e0 fs/super.c:788 __get_super include/linux/spinlock.h:329 [inline] get_super+0x2e/0x50 fs/super.c:817 fsync_bdev+0x19/0xd0 fs/block_dev.c:525 blkdev_flushbuf block/ioctl.c:436 [inline] blkdev_ioctl+0x8f1/0x1d10 block/ioctl.c:521 block_ioctl+0xee/0x130 fs/block_dev.c:1933 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c29 Code: Bad RIP value. RSP: 002b:00007fe531970c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458c29 RDX: 0000000000000000 RSI: 0000000000001261 RDI: 0000000000000004 RBP: 000000000073c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe5319716d4 R13: 00000000004bffd6 R14: 00000000004d2360 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1041: #0: 000000007ca8a1b8 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5056 1 lock held by rsyslogd/8071: #0: 0000000079d3824b (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8193: #0: 00000000a9a455e2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000ad680a48 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8194: #0: 000000007dd45a15 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000aa7789c6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8195: #0: 000000008c46cfcc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000054d253b4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8196: #0: 00000000689bb5ad (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000007fea18be (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8197: #0: 00000000df90b1ac (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000f286e736 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8198: #0: 000000007cc7121d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000458e6ae3 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8199: #0: 0000000083f9b38a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000004b1967f0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.0/14740: #0: 00000000d329d72b (&type->s_umount_key#76){.+.+}, at: __get_super.part.0+0x203/0x2e0 fs/super.c:788 1 lock held by syz-executor.0/14745: 1 lock held by syz-executor.0/14752: #0: 00000000d329d72b (&type->s_umount_key#76){.+.+}, at: __get_super.part.0+0x203/0x2e0 fs/super.c:788 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1041 Comm: khungtaskd Not tainted 5.1.0-rc4+ #67 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+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 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:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0x9b7/0xec0 kernel/hung_task.c:288 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: