INFO: task syz-executor.5:18006 can't die for more than 143 seconds. task:syz-executor.5 state:D stack:27224 pid:18006 ppid: 8692 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8eb/0x21b0 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 rwsem_down_write_slowpath+0x809/0x1220 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x132/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:773 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2211 do_new_mount_fc fs/namespace.c:2839 [inline] do_new_mount fs/namespace.c:2898 [inline] path_mount+0x1678/0x1e70 fs/namespace.c:3227 do_mount fs/namespace.c:3240 [inline] __do_sys_mount fs/namespace.c:3448 [inline] __se_sys_mount fs/namespace.c:3425 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3425 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e159 RSP: 002b:00007ff4335cfc68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e159 RDX: 0000000020002000 RSI: 00000000200042c0 RDI: 0000000000000000 RBP: 000000000119bfd0 R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffd11b9893f R14: 00007ff4335d09c0 R15: 000000000119bf8c INFO: task syz-executor.5:18006 blocked for more than 143 seconds. Not tainted 5.10.0-next-20201215-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:27224 pid:18006 ppid: 8692 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8eb/0x21b0 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 rwsem_down_write_slowpath+0x809/0x1220 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x132/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:773 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2211 do_new_mount_fc fs/namespace.c:2839 [inline] do_new_mount fs/namespace.c:2898 [inline] path_mount+0x1678/0x1e70 fs/namespace.c:3227 do_mount fs/namespace.c:3240 [inline] __do_sys_mount fs/namespace.c:3448 [inline] __se_sys_mount fs/namespace.c:3425 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3425 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e159 RSP: 002b:00007ff4335cfc68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e159 RDX: 0000000020002000 RSI: 00000000200042c0 RDI: 0000000000000000 RBP: 000000000119bfd0 R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffd11b9893f R14: 00007ff4335d09c0 R15: 000000000119bf8c INFO: task syz-executor.5:18010 can't die for more than 144 seconds. task:syz-executor.5 state:R running task stack:27296 pid:18010 ppid: 8692 flags:0x00004006 Call Trace: Showing all locks held in the system: 1 lock held by khungtaskd/1656: #0: ffffffff8b78f920 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x28c kernel/locking/lockdep.c:6254 1 lock held by in:imklog/8207: #0: ffff888018687c70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:923 2 locks held by agetty/8429: #0: ffff8880259f7098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:266 #1: ffffc90000f982e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x21d/0x1ac0 drivers/tty/n_tty.c:2158 2 locks held by kworker/u4:5/9922: 1 lock held by syz-executor.5/18006: #0: ffff88807ae98810 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline] #0: ffff88807ae98810 (&type->i_mutex_dir_key#9){++++}-{3:3}, at: lock_mount+0x8a/0x2e0 fs/namespace.c:2211 2 locks held by syz-executor.5/18010: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1656 Comm: khungtaskd Not tainted 5.10.0-next-20201215-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x3c/0xef 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+0xe75/0x1020 kernel/hung_task.c:338 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 18010 Comm: syz-executor.5 Not tainted 5.10.0-next-20201215-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__kasan_check_read+0x4/0x10 mm/kasan/shadow.c:31 Code: 14 07 48 85 db 0f 85 12 b9 16 07 48 83 c4 60 5b 5d 41 5c 41 5d c3 c3 e9 12 ba 16 07 cc cc cc cc cc cc cc cc cc cc 48 8b 0c 24 <89> f6 31 d2 e9 13 f9 ff ff 0f 1f 00 48 8b 0c 24 89 f6 ba 01 00 00 RSP: 0018:ffffc9000145f268 EFLAGS: 00000003 RAX: 000000000000002f RBX: 0000000000000000 RCX: ffffffff8157bab9 RDX: 0000000000000bee RSI: 0000000000000008 RDI: ffffffff8f513918 RBP: ffff888073d40000 R08: 0000000000000000 R09: ffffffff8f51391f R10: fffffbfff1ea2723 R11: 0000000000000001 R12: 0000000000000bee R13: 0000000000000004 R14: dffffc0000000000 R15: ffff888073d40990 FS: 00007ff4335af700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbbfa738000 CR3: 00000000215bb000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] hlock_class kernel/locking/lockdep.c:198 [inline] check_wait_context kernel/locking/lockdep.c:4531 [inline] __lock_acquire+0x709/0x54b0 kernel/locking/lockdep.c:4782 lock_acquire kernel/locking/lockdep.c:5437 [inline] lock_acquire+0x29d/0x750 kernel/locking/lockdep.c:5402 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] find_inode+0x109/0x220 fs/inode.c:826 ilookup5_nowait fs/inode.c:1334 [inline] ilookup5 fs/inode.c:1363 [inline] iget5_locked+0xbd/0x2d0 fs/inode.c:1144 fuse_iget+0x271/0x610 fs/fuse/inode.c:342 fuse_lookup_name+0x447/0x630 fs/fuse/dir.c:439 fuse_lookup.part.0+0xdf/0x390 fs/fuse/dir.c:469 fuse_lookup fs/fuse/dir.c:465 [inline] fuse_atomic_open+0x2de/0x440 fs/fuse/dir.c:621 atomic_open fs/namei.c:2970 [inline] lookup_open.isra.0+0xc3d/0x13d0 fs/namei.c:3076 open_last_lookups fs/namei.c:3178 [inline] path_openat+0x9af/0x27a0 fs/namei.c:3366 do_filp_open+0x17e/0x3c0 fs/namei.c:3396 do_sys_openat2+0x16d/0x420 fs/open.c:1172 do_sys_open fs/open.c:1188 [inline] __do_sys_openat fs/open.c:1204 [inline] __se_sys_openat fs/open.c:1199 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1199 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e159 Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ff4335aec68 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045e159 RDX: 0000000000000000 RSI: 0000000020002040 RDI: ffffffffffffff9c RBP: 000000000119c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c034 R13: 00007ffd11b9893f R14: 00007ff4335af9c0 R15: 000000000119c034