INFO: task syz-executor3:13565 blocked for more than 140 seconds. Not tainted 4.18.0-rc7+ #79 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D23288 13565 4415 0x20020004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_write_failed_common+0x95d/0x1630 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_nested+0xae/0x130 kernel/locking/rwsem.c:194 inode_lock_nested include/linux/fs.h:750 [inline] do_unlinkat+0x3d8/0xa30 fs/namei.c:4059 __do_sys_unlinkat fs/namei.c:4115 [inline] __se_sys_unlinkat fs/namei.c:4107 [inline] __ia32_sys_unlinkat+0xc6/0x120 fs/namei.c:4107 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f6bcb9 Code: Bad RIP value. RSP: 002b:00000000f5f670cc EFLAGS: 00000296 ORIG_RAX: 000000000000012d RAX: ffffffffffffffda RBX: 0000000000000015 RCX: 0000000020000180 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor3:13571 blocked for more than 140 seconds. Not tainted 4.18.0-rc7+ #79 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D21944 13571 4415 0x20020004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 request_wait_answer+0x4c8/0x920 fs/fuse/dev.c:463 __fuse_request_send+0x12a/0x1d0 fs/fuse/dev.c:483 fuse_request_send+0x62/0xa0 fs/fuse/dev.c:496 fuse_simple_request+0x33d/0x730 fs/fuse/dev.c:554 fuse_lookup_name+0x3ee/0x830 fs/fuse/dir.c:323 fuse_lookup+0xf9/0x4c0 fs/fuse/dir.c:360 fuse_atomic_open+0x214/0x350 fs/fuse/dir.c:499 atomic_open fs/namei.c:3054 [inline] lookup_open+0xdb1/0x1b40 fs/namei.c:3190 do_last fs/namei.c:3311 [inline] path_openat+0x207d/0x4e10 fs/namei.c:3540 do_filp_open+0x255/0x380 fs/namei.c:3574 do_open_execat+0x1fe/0x670 fs/exec.c:853 __do_execve_file.isra.36+0x177f/0x25e0 fs/exec.c:1754 do_execveat_common fs/exec.c:1865 [inline] compat_do_execveat fs/exec.c:1925 [inline] __do_compat_sys_execveat fs/exec.c:1995 [inline] __se_compat_sys_execveat fs/exec.c:1987 [inline] __ia32_compat_sys_execveat+0xf3/0x140 fs/exec.c:1987 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f6bcb9 Code: Bad RIP value. RSP: 002b:00000000f5f460cc EFLAGS: 00000296 ORIG_RAX: 0000000000000166 RAX: ffffffffffffffda RBX: 0000000000000015 RCX: 0000000020000080 RDX: 0000000020000280 RSI: 0000000020000340 RDI: 0000000000000100 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/773: #0: 0000000045f5b209 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4461 1 lock held by rsyslogd/4275: 2 locks held by getty/4365: #0: 0000000008979cc9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000c6331314 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4366: #0: 0000000009ccbb2e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000004bb4bed9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4367: #0: 000000003f77dbbc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000006531273a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4368: #0: 0000000087c7938a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000ae5b2342 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4369: #0: 00000000a1e3f2b8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000076d2d897 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4370: #0: 00000000e39b4127 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000947c1884 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4371: #0: 0000000048b26898 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000c7c7b7cd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by syz-executor3/13565: #0: 000000006dbb9291 (sb_writers#17){.+.+}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 000000006dbb9291 (sb_writers#17){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 #1: 000000002eb8882f (&type->i_mutex_dir_key#5/1){+.+.}, at: inode_lock_nested include/linux/fs.h:750 [inline] #1: 000000002eb8882f (&type->i_mutex_dir_key#5/1){+.+.}, at: do_unlinkat+0x3d8/0xa30 fs/namei.c:4059 3 locks held by syz-executor3/13571: #0: 00000000a80dea99 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x53/0x120 fs/exec.c:1403 #1: 000000002eb8882f (&type->i_mutex_dir_key#5){++++}, at: inode_lock_shared include/linux/fs.h:725 [inline] #1: 000000002eb8882f (&type->i_mutex_dir_key#5){++++}, at: do_last fs/namei.c:3310 [inline] #1: 000000002eb8882f (&type->i_mutex_dir_key#5){++++}, at: path_openat+0x204c/0x4e10 fs/namei.c:3540 #2: 0000000081c84b40 (&fi->mutex){+.+.}, at: fuse_lock_inode+0xaf/0xe0 fs/fuse/inode.c:363 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 773 Comm: khungtaskd Not tainted 4.18.0-rc7+ #79 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:138 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline] watchdog+0x9c4/0xf80 kernel/hung_task.c:252 kthread+0x345/0x410 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54