INFO: task syz-executor.5:10148 blocked for more than 143 seconds. Not tainted 5.10.0-rc4-next-20201123-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:28624 pid:10148 ppid: 8630 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4316 [inline] __schedule+0x896/0x2050 kernel/sched/core.c:5067 schedule+0xcf/0x270 kernel/sched/core.c:5146 io_uring_cancel_files fs/io_uring.c:8745 [inline] io_uring_cancel_task_requests fs/io_uring.c:8797 [inline] __io_uring_files_cancel+0xc4d/0x14b0 fs/io_uring.c:8893 io_uring_files_cancel include/linux/io_uring.h:51 [inline] exit_files+0xe4/0x170 fs/file.c:456 do_exit+0xb61/0x29f0 kernel/exit.c:818 do_group_exit+0x125/0x310 kernel/exit.c:920 get_signal+0x3ec/0x2010 kernel/signal.c:2770 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811 handle_signal_work kernel/entry/common.c:144 [inline] exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x124/0x200 kernel/entry/common.c:198 syscall_exit_to_user_mode+0x36/0x260 kernel/entry/common.c:275 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45deb9 RSP: 002b:00007f33c2603cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000118bf28 RCX: 000000000045deb9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000118bf28 RBP: 000000000118bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c R13: 00007ffe1388514f R14: 00007f33c26049c0 R15: 000000000118bf2c Showing all locks held in the system: 2 locks held by kworker/u4:2/51: 1 lock held by khungtaskd/1656: #0: ffffffff8b339e60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6254 2 locks held by kworker/0:3/4223: 1 lock held by in:imklog/8199: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1656 Comm: khungtaskd Not tainted 5.10.0-rc4-next-20201123-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: 4886 Comm: systemd-journal Not tainted 5.10.0-rc4-next-20201123-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0xd98/0x5500 kernel/locking/lockdep.c:4702 Code: 3f 1f 0d e9 83 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 f2 48 c1 ea 03 80 3c 02 00 0f 85 72 30 00 00 49 81 3e 80 c2 4a 8e <0f> 84 44 f3 ff ff 41 83 fc 01 0f 87 46 f3 ff ff 44 89 e0 0f 87 a3 RSP: 0018:ffffc9000162f860 EFLAGS: 00000002 RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 1ffffffff1e1454e RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff888025d03580 R08: 0000000000000001 R09: 0000000000000001 R10: fffffbfff19daac9 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8f0a2a70 R15: 0000000000000000 FS: 00007f0e9cf288c0(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0e9a342000 CR3: 00000000110c6000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5437 [inline] lock_acquire+0x29d/0x740 kernel/locking/lockdep.c:5402 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:159 __debug_check_no_obj_freed lib/debugobjects.c:975 [inline] debug_check_no_obj_freed+0xc7/0x420 lib/debugobjects.c:1018 free_pages_prepare mm/page_alloc.c:1268 [inline] __free_pages_ok+0x2ef/0xf20 mm/page_alloc.c:1528 unfreeze_partials+0x16c/0x1b0 mm/slub.c:2362 put_cpu_partial+0x129/0x200 mm/slub.c:2398 qlink_free mm/kasan/quarantine.c:149 [inline] qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:168 quarantine_reduce+0x17e/0x200 mm/kasan/quarantine.c:261 __kasan_kmalloc.constprop.0+0x9e/0xd0 mm/kasan/common.c:458 slab_post_alloc_hook mm/slab.h:512 [inline] slab_alloc_node mm/slub.c:2900 [inline] slab_alloc mm/slub.c:2908 [inline] kmem_cache_alloc+0x12a/0x470 mm/slub.c:2913 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138 getname_flags include/linux/audit.h:319 [inline] getname+0x8e/0xd0 fs/namei.c:209 do_sys_openat2+0xf5/0x420 fs/open.c:1162 do_sys_open fs/open.c:1184 [inline] __do_sys_open fs/open.c:1192 [inline] __se_sys_open fs/open.c:1188 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1188 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f0e9c4b8840 Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 RSP: 002b:00007ffe9ecda218 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffe9ecda520 RCX: 00007f0e9c4b8840 RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 000055721fe59490 RBP: 000000000000000d R08: 000000000000c0c1 R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff R13: 000055721fe4c040 R14: 00007ffe9ecda4e0 R15: 000055721fe5a3d0