INFO: task syz-executor.5:27166 blocked for more than 143 seconds. Not tainted 5.1.0-rc1+ #31 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29024 27166 15197 0x00000004 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 __do_sys_acct kernel/acct.c:285 [inline] __se_sys_acct kernel/acct.c:273 [inline] __x64_sys_acct+0xa6/0x200 kernel/acct.c:273 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458079 Code: Bad RIP value. RSP: 002b:00007fbfff007c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a3 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000458079 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000000 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbfff0086d4 R13: 00000000004bdee5 R14: 00000000004ce370 R15: 00000000ffffffff INFO: task syz-executor.1:27283 blocked for more than 143 seconds. Not tainted 5.1.0-rc1+ #31 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28368 27283 15934 0x00000000 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 __do_sys_acct kernel/acct.c:285 [inline] __se_sys_acct kernel/acct.c:273 [inline] __x64_sys_acct+0xa6/0x200 kernel/acct.c:273 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458079 Code: Bad RIP value. RSP: 002b:00007f9f88efbc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a3 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000458079 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000000 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9f88efc6d4 R13: 00000000004bdee5 R14: 00000000004ce370 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1042: #0: 00000000c246cf1a (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5061 2 locks held by udevd/3875: 1 lock held by rsyslogd/8080: #0: 00000000d81ce0f4 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8224: #0: 0000000021aeb9b6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e8fd0b3a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8225: #0: 00000000d47ad70a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000001dcd0334 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8226: #0: 000000005e3f4861 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000026505f2a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8227: #0: 000000003487e77e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000683c1335 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8228: #0: 0000000020191643 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000fe58a202 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8229: #0: 0000000049023ec7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000b9b3fe9c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8230: #0: 00000000764cd916 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000007b9af41e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.5/27166: #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __do_sys_acct kernel/acct.c:285 [inline] #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __se_sys_acct kernel/acct.c:273 [inline] #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __x64_sys_acct+0xa6/0x200 kernel/acct.c:273 1 lock held by syz-executor.1/27171: #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __do_sys_acct kernel/acct.c:285 [inline] #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __se_sys_acct kernel/acct.c:273 [inline] #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __x64_sys_acct+0xa6/0x200 kernel/acct.c:273 1 lock held by syz-executor.1/27283: #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __do_sys_acct kernel/acct.c:285 [inline] #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __se_sys_acct kernel/acct.c:273 [inline] #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __x64_sys_acct+0xa6/0x200 kernel/acct.c:273 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1042 Comm: khungtaskd Not tainted 5.1.0-rc1+ #31 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 0 to CPUs 1: