INFO: task syz-executor.1:18679 can't die for more than 143 seconds. task:syz-executor.1 state:D stack:27896 pid:18679 ppid: 6896 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:3777 [inline] __schedule+0xec5/0x2200 kernel/sched/core.c:4526 schedule+0xcf/0x270 kernel/sched/core.c:4604 request_wait_answer+0x505/0x7f0 fs/fuse/dev.c:402 __fuse_request_send fs/fuse/dev.c:421 [inline] fuse_simple_request+0x526/0xc10 fs/fuse/dev.c:503 fuse_lookup_name+0x258/0x5c0 fs/fuse/dir.c:352 fuse_lookup+0xdf/0x390 fs/fuse/dir.c:390 fuse_atomic_open+0x210/0x340 fs/fuse/dir.c:533 atomic_open fs/namei.c:2970 [inline] lookup_open.isra.0+0xc09/0x1350 fs/namei.c:3076 open_last_lookups fs/namei.c:3178 [inline] path_openat+0x96d/0x2730 fs/namei.c:3366 do_filp_open+0x17e/0x3c0 fs/namei.c:3396 do_sys_openat2+0x16d/0x420 fs/open.c:1168 do_sys_open fs/open.c:1184 [inline] __do_sys_openat fs/open.c:1200 [inline] __se_sys_openat fs/open.c:1195 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1195 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e179 Code: Bad RIP value. RSP: 002b:00007f6fa2be6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000021e00 RCX: 000000000045e179 RDX: 0000000000000000 RSI: 0000000020002040 RDI: ffffffffffffff9c RBP: 000000000118cf88 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 00007ffe5df4014f R14: 00007f6fa2be79c0 R15: 000000000118cf4c INFO: task syz-executor.1:18679 blocked for more than 143 seconds. Not tainted 5.9.0-rc6-next-20200922-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:27896 pid:18679 ppid: 6896 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:3777 [inline] __schedule+0xec5/0x2200 kernel/sched/core.c:4526 schedule+0xcf/0x270 kernel/sched/core.c:4604 request_wait_answer+0x505/0x7f0 fs/fuse/dev.c:402 __fuse_request_send fs/fuse/dev.c:421 [inline] fuse_simple_request+0x526/0xc10 fs/fuse/dev.c:503 fuse_lookup_name+0x258/0x5c0 fs/fuse/dir.c:352 fuse_lookup+0xdf/0x390 fs/fuse/dir.c:390 fuse_atomic_open+0x210/0x340 fs/fuse/dir.c:533 atomic_open fs/namei.c:2970 [inline] lookup_open.isra.0+0xc09/0x1350 fs/namei.c:3076 open_last_lookups fs/namei.c:3178 [inline] path_openat+0x96d/0x2730 fs/namei.c:3366 do_filp_open+0x17e/0x3c0 fs/namei.c:3396 do_sys_openat2+0x16d/0x420 fs/open.c:1168 do_sys_open fs/open.c:1184 [inline] __do_sys_openat fs/open.c:1200 [inline] __se_sys_openat fs/open.c:1195 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1195 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e179 Code: Bad RIP value. RSP: 002b:00007f6fa2be6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000021e00 RCX: 000000000045e179 RDX: 0000000000000000 RSI: 0000000020002040 RDI: ffffffffffffff9c RBP: 000000000118cf88 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 00007ffe5df4014f R14: 00007f6fa2be79c0 R15: 000000000118cf4c Showing all locks held in the system: 1 lock held by khungtaskd/1181: #0: ffffffff8a503c80 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6221 2 locks held by agetty/6779: #0: ffff8880a1d2b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:266 #1: ffffc900010602e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a70 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.1/18679: #0: ffff88804d8119d0 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:792 [inline] #0: ffff88804d8119d0 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: open_last_lookups fs/namei.c:3177 [inline] #0: ffff88804d8119d0 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: path_openat+0x14a3/0x2730 fs/namei.c:3366 #1: ffff88804d811da8 (&fi->mutex){+.+.}-{3:3}, at: fuse_lock_inode+0xaf/0xe0 fs/fuse/inode.c:375 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1181 Comm: khungtaskd Not tainted 5.9.0-rc6-next-20200922-syzkaller #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+0x198/0x1fb lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline] watchdog+0xd89/0xf30 kernel/hung_task.c:339 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3919 Comm: systemd-journal Not tainted 5.9.0-rc6-next-20200922-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:367 [inline] RIP: 0010:trace_lock_acquire include/trace/events/lock.h:13 [inline] RIP: 0010:lock_acquire+0x99/0xaa0 kernel/locking/lockdep.c:5372 Code: f3 f3 65 48 8b 04 25 28 00 00 00 48 89 84 24 b0 00 00 00 31 c0 0f 1f 44 00 00 65 8b 15 20 62 a6 7e 83 fa 3f 0f 87 00 07 00 00 <89> d2 be 08 00 00 00 48 89 d0 48 89 14 24 48 c1 f8 06 48 8d 3c c5 RSP: 0018:ffffc900010f7cb0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 1ffff9200021ef99 RCX: 0000000000000002 RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffffffff8a503c80 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: ffffffff8a503c80 R15: 0000000000000000 FS: 00007f0e26fd58c0(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0e244c3000 CR3: 00000000925f4000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:253 [inline] rcu_read_lock include/linux/rcupdate.h:642 [inline] mntput_no_expire+0xa3/0xd20 fs/namespace.c:1148 mntput+0x67/0x90 fs/namespace.c:1221 do_faccessat+0x31c/0x820 fs/open.c:457 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f0e262919c7 Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffe11dfdcf8 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007ffe11e00c10 RCX: 00007f0e262919c7 RDX: 00007f0e26d02a00 RSI: 0000000000000000 RDI: 00005587e5c1c9a3 RBP: 00007ffe11dfdd30 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffe11e00c10 R15: 00007ffe11dfe220