INFO: task syz-executor.5:31048 can't die for more than 143 seconds. syz-executor.5 D28360 31048 7448 0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 io_uring_cancel_files fs/io_uring.c:7897 [inline] io_uring_flush+0x740/0xa90 fs/io_uring.c:7914 filp_close+0xb4/0x170 fs/open.c:1276 __close_fd+0x2f/0x50 fs/file.c:671 __do_sys_close fs/open.c:1295 [inline] __se_sys_close fs/open.c:1293 [inline] __x64_sys_close+0x69/0x100 fs/open.c:1293 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x416981 Code: Bad RIP value. RSP: 002b:00007ffe164f4ff0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000416981 RDX: 0000000000000000 RSI: 00000000000010bc RDI: 0000000000000003 RBP: 0000000000000001 R08: 00000000102b50bc R09: 00000000102b50c0 R10: 00007ffe164f50e0 R11: 0000000000000293 R12: 0000000001191d50 R13: 0000000000126257 R14: ffffffffffffffff R15: 000000000118bf2c INFO: task syz-executor.5:31048 blocked for more than 143 seconds. Not tainted 5.8.0-next-20200810-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28360 31048 7448 0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 io_uring_cancel_files fs/io_uring.c:7897 [inline] io_uring_flush+0x740/0xa90 fs/io_uring.c:7914 filp_close+0xb4/0x170 fs/open.c:1276 __close_fd+0x2f/0x50 fs/file.c:671 __do_sys_close fs/open.c:1295 [inline] __se_sys_close fs/open.c:1293 [inline] __x64_sys_close+0x69/0x100 fs/open.c:1293 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x416981 Code: Bad RIP value. RSP: 002b:00007ffe164f4ff0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000416981 RDX: 0000000000000000 RSI: 00000000000010bc RDI: 0000000000000003 RBP: 0000000000000001 R08: 00000000102b50bc R09: 00000000102b50c0 R10: 00007ffe164f50e0 R11: 0000000000000293 R12: 0000000001191d50 R13: 0000000000126257 R14: ffffffffffffffff R15: 000000000118bf2c Showing all locks held in the system: 1 lock held by khungtaskd/1170: #0: ffffffff89c66c40 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5825 1 lock held by in:imklog/6542: #0: ffff88809e544630 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1170 Comm: khungtaskd Not tainted 5.8.0-next-20200810-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+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 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+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6543 Comm: rs:main Q:Reg Not tainted 5.8.0-next-20200810-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0033:0x55c2017dc011 Code: e7 e8 03 5d fc ff 4c 89 e7 48 89 c5 e8 d8 5c fc ff 48 63 54 24 2c 4c 63 e0 89 44 24 1c 48 89 d8 4c 01 e0 48 01 d0 80 7d 00 20 <41> 0f 95 c5 4d 8d 6c 05 13 41 8b 47 08 49 39 c5 72 13 4c 89 ee 4c RSP: 002b:00007faa8110e810 EFLAGS: 00000202 RAX: 0000000000000032 RBX: 0000000000000009 RCX: 0000000000000000 RDX: 0000000000000007 RSI: 00007faa8110e840 RDI: 00007faa7401fb70 RBP: 00007faa7401fcb0 R08: 0000000000000000 R09: 0000000000000000 R10: 000055c201a19280 R11: 0000000000000000 R12: 0000000000000022 R13: 0000000000000000 R14: 00007faa7401fd68 R15: 00007faa78019c00 FS: 00007faa8110f700 GS: 0000000000000000