INFO: task syz-executor.3:31433 can't die for more than 143 seconds. syz-executor.3 D28184 31433 8718 0x00004004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94a/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 rwsem_down_write_slowpath+0x706/0xf80 kernel/locking/rwsem.c:1238 __down_write kernel/locking/rwsem.c:1392 [inline] down_write+0x13c/0x150 kernel/locking/rwsem.c:1535 inode_lock include/linux/fs.h:791 [inline] lock_mount+0x8c/0x2e0 fs/namespace.c:2134 do_add_mount+0x27/0x380 fs/namespace.c:2708 do_new_mount_fc fs/namespace.c:2771 [inline] do_new_mount fs/namespace.c:2824 [inline] do_mount+0x1701/0x1b50 fs/namespace.c:3142 ksys_mount+0xdb/0x150 fs/namespace.c:3351 __do_sys_mount fs/namespace.c:3365 [inline] __se_sys_mount fs/namespace.c:3362 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3362 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459a59 Code: Bad RIP value. RSP: 002b:00007f3c84d14c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459a59 RDX: 0000000020000300 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 000000000075c070 R08: 00000000200005c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3c84d156d4 R13: 00000000004c6252 R14: 00000000004db3a8 R15: 00000000ffffffff INFO: task syz-executor.3:31433 blocked for more than 143 seconds. Not tainted 5.4.0-rc3-next-20191018 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28184 31433 8718 0x00004004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94a/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 rwsem_down_write_slowpath+0x706/0xf80 kernel/locking/rwsem.c:1238 __down_write kernel/locking/rwsem.c:1392 [inline] down_write+0x13c/0x150 kernel/locking/rwsem.c:1535 inode_lock include/linux/fs.h:791 [inline] lock_mount+0x8c/0x2e0 fs/namespace.c:2134 do_add_mount+0x27/0x380 fs/namespace.c:2708 do_new_mount_fc fs/namespace.c:2771 [inline] do_new_mount fs/namespace.c:2824 [inline] do_mount+0x1701/0x1b50 fs/namespace.c:3142 ksys_mount+0xdb/0x150 fs/namespace.c:3351 __do_sys_mount fs/namespace.c:3365 [inline] __se_sys_mount fs/namespace.c:3362 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3362 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459a59 Code: Bad RIP value. RSP: 002b:00007f3c84d14c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459a59 RDX: 0000000020000300 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 000000000075c070 R08: 00000000200005c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3c84d156d4 R13: 00000000004c6252 R14: 00000000004db3a8 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1073: #0: ffffffff88fab740 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5336 2 locks held by rsyslogd/8579: #0: ffff8880a3ced8e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 #1: ffffffff88fab740 (rcu_read_lock){....}, at: syslog_print kernel/printk/printk.c:1364 [inline] #1: ffffffff88fab740 (rcu_read_lock){....}, at: do_syslog kernel/printk/printk.c:1529 [inline] #1: ffffffff88fab740 (rcu_read_lock){....}, at: do_syslog+0x699/0x1870 kernel/printk/printk.c:1503 2 locks held by getty/8669: #0: ffff888093a7f090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f312e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8670: #0: ffff888098140090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8671: #0: ffff88809ae00090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f0d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8672: #0: ffff8880a9a48090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f212e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8673: #0: ffff8880a49ab090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f2d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8674: #0: ffff8880a754f090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f252e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8675: #0: ffff88809a8a9090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f012e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.3/31392: #0: ffff88809c088428 (sb_writers#18){.+.+}, at: sb_start_write include/linux/fs.h:1650 [inline] #0: ffff88809c088428 (sb_writers#18){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:354 #1: ffff8880a30e9a90 (&sb->s_type->i_mutex_key#27/1){+.+.}, at: inode_lock_nested include/linux/fs.h:826 [inline] #1: ffff8880a30e9a90 (&sb->s_type->i_mutex_key#27/1){+.+.}, at: filename_create+0x17c/0x4f0 fs/namei.c:3630 1 lock held by syz-executor.3/31433: #0: ffff8880a30e9a90 (&sb->s_type->i_mutex_key#28){++++}, at: inode_lock include/linux/fs.h:791 [inline] #0: ffff8880a30e9a90 (&sb->s_type->i_mutex_key#28){++++}, at: lock_mount+0x8c/0x2e0 fs/namespace.c:2134 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1073 Comm: khungtaskd Not tainted 5.4.0-rc3-next-20191018 #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+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b 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:269 [inline] watchdog+0xc8f/0x1350 kernel/hung_task.c:353 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60