INFO: task syz-executor.5:19319 can't die for more than 143 seconds. task:syz-executor.5 state:D stack:27224 pid:19319 ppid: 11845 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:00007f363eb40c68 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: 00007fff75b830af R14: 00007f363eb419c0 R15: 000000000119bf8c INFO: task syz-executor.5:19319 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:19319 ppid: 11845 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:00007f363eb40c68 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: 00007fff75b830af R14: 00007f363eb419c0 R15: 000000000119bf8c INFO: task syz-executor.5:19329 can't die for more than 144 seconds. task:syz-executor.5 state:R running task stack:27104 pid:19329 ppid: 11845 flags:0x00004006 Call Trace: Showing all locks held in the system: 3 locks held by kworker/u4:3/137: 1 lock held by khungtaskd/1655: #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/8199: #0: ffff888017246370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:923 2 locks held by agetty/8219: #0: ffff88802183e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:266 #1: ffffc90000f8c2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x21d/0x1ac0 drivers/tty/n_tty.c:2158 1 lock held by syz-executor.5/19319: #0: ffff88806843b090 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline] #0: ffff88806843b090 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: lock_mount+0x8a/0x2e0 fs/namespace.c:2211 2 locks held by syz-executor.5/19329: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1655 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: 19329 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:check_memory_region+0x16/0x180 mm/kasan/generic.c:185 Code: 02 0f 1f 00 48 89 f2 be f8 00 00 00 e9 13 53 28 02 0f 1f 00 48 85 f6 0f 84 70 01 00 00 49 89 f9 41 54 44 0f b6 c2 49 01 f1 55 <53> 0f 82 18 01 00 00 48 b8 ff ff ff ff ff 7f ff ff 48 39 c7 0f 86 RSP: 0018:ffffc90009f1f4f0 EFLAGS: 00000292 RAX: 0000000000000000 RBX: ffffc90009f1f5c0 RCX: ffffffff81c871f6 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88806843b018 RBP: ffff888022a0c000 R08: 0000000000000000 R09: ffff88806843b020 R10: ffffffff81c8719b R11: 0000000000000001 R12: ffff88806843af40 R13: ffffffff82a1b560 R14: ffff88806843b018 R15: dffffc0000000000 FS: 00007f363eaff700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f19ca2aa000 CR3: 0000000013aaa000 CR4: 00000000001506f0 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] wait_on_bit include/linux/wait_bit.h:74 [inline] wait_on_inode include/linux/writeback.h:206 [inline] ilookup5 fs/inode.c:1365 [inline] iget5_locked+0x136/0x2d0 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:00007f363eafec68 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045e159 RDX: 0000000000000000 RSI: 0000000020002040 RDI: ffffffffffffff9c RBP: 000000000119c118 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c0dc R13: 00007fff75b830af R14: 00007f363eaff9c0 R15: 000000000119c0dc