INFO: task syz-executor.4:10003 can't die for more than 143 seconds. task:syz-executor.4 state:D stack:27072 pid:10003 ppid: 8492 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8cd/0x2150 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 rwsem_down_write_slowpath+0x7e5/0x1200 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:2214 do_new_mount_fc fs/namespace.c:2842 [inline] do_new_mount fs/namespace.c:2901 [inline] path_mount+0x1678/0x1e70 fs/namespace.c:3230 do_mount fs/namespace.c:3243 [inline] __do_sys_mount fs/namespace.c:3451 [inline] __se_sys_mount fs/namespace.c:3428 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3428 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e299 RSP: 002b:00007fc8c32cbc68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e299 RDX: 0000000020002000 RSI: 00000000200042c0 RDI: 0000000000000000 RBP: 000000000119c078 R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c034 R13: 00007ffcfd0d07af R14: 00007fc8c32cc9c0 R15: 000000000119c034 INFO: task syz-executor.4:10003 blocked for more than 143 seconds. Not tainted 5.10.0-next-20201223-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:27072 pid:10003 ppid: 8492 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8cd/0x2150 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 rwsem_down_write_slowpath+0x7e5/0x1200 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:2214 do_new_mount_fc fs/namespace.c:2842 [inline] do_new_mount fs/namespace.c:2901 [inline] path_mount+0x1678/0x1e70 fs/namespace.c:3230 do_mount fs/namespace.c:3243 [inline] __do_sys_mount fs/namespace.c:3451 [inline] __se_sys_mount fs/namespace.c:3428 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3428 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e299 RSP: 002b:00007fc8c32cbc68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e299 RDX: 0000000020002000 RSI: 00000000200042c0 RDI: 0000000000000000 RBP: 000000000119c078 R08: 0000000020002140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c034 R13: 00007ffcfd0d07af R14: 00007fc8c32cc9c0 R15: 000000000119c034 INFO: task syz-executor.4:10007 can't die for more than 144 seconds. task:syz-executor.4 state:R running task stack:27192 pid:10007 ppid: 8492 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8cd/0x2150 kernel/sched/core.c:5078 Showing all locks held in the system: 1 lock held by khungtaskd/1660: #0: ffffffff8b363660 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6254 1 lock held by in:imklog/8166: #0: ffff88801c1974f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:949 1 lock held by syz-executor.4/10003: #0: ffff88807e838150 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline] #0: ffff88807e838150 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: lock_mount+0x8a/0x2e0 fs/namespace.c:2214 3 locks held by syz-executor.4/10007: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1660 Comm: khungtaskd Not tainted 5.10.0-next-20201223-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+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: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: 10007 Comm: syz-executor.4 Not tainted 5.10.0-next-20201223-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:memory_is_nonzero mm/kasan/generic.c:101 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_memory_region_inline mm/kasan/generic.c:177 [inline] RIP: 0010:check_memory_region+0x5c/0x180 mm/kasan/generic.c:186 Code: e9 01 48 89 fd 48 b8 00 00 00 00 00 fc ff df 4d 89 ca 48 c1 ed 03 49 c1 ea 03 48 01 c5 49 01 c2 48 89 e8 49 8d 5a 01 48 89 da <48> 29 ea 48 83 fa 10 7e 63 41 89 eb 41 83 e3 07 75 74 4c 8d 5a 07 RSP: 0018:ffffc90016b0f548 EFLAGS: 00000282 RAX: ffffed100fd07097 RBX: ffffed100fd07098 RCX: ffffffff82a18dae RDX: ffffed100fd07098 RSI: 0000000000000008 RDI: ffff88807e8384b8 RBP: ffffed100fd07097 R08: 0000000000000001 R09: ffff88807e8384bf R10: ffffed100fd07097 R11: 0000000000000000 R12: ffffc90016b0f838 R13: ffff88807a9ec000 R14: 0000000000002000 R15: ffffc90016b0f5c0 FS: 00007fc8c32ab700(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffbd4c0b000 CR3: 00000000270b1000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: instrument_atomic_write include/linux/instrumented.h:86 [inline] set_bit include/asm-generic/bitops/instrumented-atomic.h:28 [inline] fuse_make_bad fs/fuse/fuse_i.h:866 [inline] fuse_iget+0x23e/0x610 fs/fuse/inode.c:355 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:2972 [inline] lookup_open.isra.0+0xc09/0x1350 fs/namei.c:3078 open_last_lookups fs/namei.c:3180 [inline] path_openat+0x96d/0x2730 fs/namei.c:3368 do_filp_open+0x17e/0x3c0 fs/namei.c:3398 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: 0033:0x45e299 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:00007fc8c32aac68 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045e299 RDX: 0000000000000000 RSI: 0000000020002040 RDI: ffffffffffffff9c RBP: 000000000119c118 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c0dc R13: 00007ffcfd0d07af R14: 00007fc8c32ab9c0 R15: 000000000119c0dc