INFO: task syz-executor0:6459 blocked for more than 140 seconds. Not tainted 4.19.0-rc6+ #39 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D24000 6459 5394 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 __rwsem_down_write_failed_common+0xbb9/0x1670 kernel/locking/rwsem-xadd.c:566 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:595 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0xa5/0x130 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:738 [inline] utimes_common.isra.1+0x45c/0x8e0 fs/utimes.c:90 do_utimes+0x1f7/0x380 fs/utimes.c:156 do_futimesat+0x250/0x350 fs/utimes.c:212 __do_sys_utimes fs/utimes.c:225 [inline] __se_sys_utimes fs/utimes.c:222 [inline] __x64_sys_utimes+0x59/0x80 fs/utimes.c:222 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457579 Code: Bad RIP value. RSP: 002b:00007f324d546c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000eb RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457579 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 00000000200000c0 RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f324d5476d4 R13: 00000000004c4f5a R14: 00000000004d8508 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/983: #0: 000000003b2f831d (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4435 1 lock held by rsyslogd/5264: #0: 00000000f2907662 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5354: #0: 000000008b1c498a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000006590da75 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5355: #0: 000000009f400e55 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000513c2dcd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5356: #0: 00000000e879177d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000f27f2cb6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5357: #0: 000000007dae0749 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000e97b2928 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5358: #0: 000000006b53a6f3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000057616acd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5359: #0: 00000000b3412108 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000009a876c40 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5360: #0: 00000000159e259a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000000bc4bab (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by syz-executor0/6455: #0: 00000000569c1e7b (sb_writers#18){.+.+}, at: sb_start_write include/linux/fs.h:1566 [inline] #0: 00000000569c1e7b (sb_writers#18){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:360 #1: 000000007d610dd5 (&sb->s_type->i_mutex_key#24){++++}, at: inode_lock include/linux/fs.h:738 [inline] #1: 000000007d610dd5 (&sb->s_type->i_mutex_key#24){++++}, at: utimes_common.isra.1+0x45c/0x8e0 fs/utimes.c:90 2 locks held by syz-executor0/6459: #0: 00000000569c1e7b (sb_writers#18){.+.+}, at: sb_start_write include/linux/fs.h:1566 [inline] #0: 00000000569c1e7b (sb_writers#18){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:360 #1: 000000007d610dd5 (&sb->s_type->i_mutex_key#24){++++}, at: inode_lock include/linux/fs.h:738 [inline] #1: 000000007d610dd5 (&sb->s_type->i_mutex_key#24){++++}, at: utimes_common.isra.1+0x45c/0x8e0 fs/utimes.c:90 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 983 Comm: khungtaskd Not tainted 4.19.0-rc6+ #39 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+0x1c4/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed 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:204 [inline] watchdog+0xb3e/0x1050 kernel/hung_task.c:265 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:57