INFO: task syz-executor.4:25763 blocked for more than 143 seconds. Not tainted 5.10.0-rc4-next-20201117-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:29240 pid:25763 ppid: 10761 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4269 [inline] __schedule+0x890/0x2030 kernel/sched/core.c:5019 schedule+0xcf/0x270 kernel/sched/core.c:5098 io_uring_cancel_files fs/io_uring.c:8720 [inline] io_uring_cancel_task_requests fs/io_uring.c:8772 [inline] __io_uring_files_cancel+0xc4d/0x14b0 fs/io_uring.c:8868 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+0x3ea/0x1f70 kernel/signal.c:2750 arch_do_signal_or_restart+0x2a6/0x1ea0 arch/x86/kernel/signal.c:811 handle_signal_work kernel/entry/common.c:145 [inline] exit_to_user_mode_loop kernel/entry/common.c:169 [inline] exit_to_user_mode_prepare+0x124/0x200 kernel/entry/common.c:199 syscall_exit_to_user_mode+0x38/0x260 kernel/entry/common.c:274 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45deb9 Code: Unable to access opcode bytes at RIP 0x45de8f. RSP: 002b:00007f6ae617fcf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000118bfd0 RCX: 000000000045deb9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000118bfd0 RBP: 000000000118bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bfd4 R13: 00007ffcd99acf1f R14: 00007f6ae61809c0 R15: 000000000118bfd4 Showing all locks held in the system: 1 lock held by khungtaskd/1621: #0: ffffffff8b339ca0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6252 1 lock held by in:imklog/8185: #0: ffff88801376c0f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:932 2 locks held by kworker/u4:9/24138: #0: ffff8880b9f34f98 (&rq->lock){-.-.}-{2:2}, at: newidle_balance+0x789/0xe50 kernel/sched/fair.c:10622 #1: ffffffff8b339ca0 (rcu_read_lock){....}-{1:2}, at: cpu_of kernel/sched/sched.h:1085 [inline] #1: ffffffff8b339ca0 (rcu_read_lock){....}-{1:2}, at: __update_idle_core+0x39/0x430 kernel/sched/fair.c:6039 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1621 Comm: khungtaskd Not tainted 5.10.0-rc4-next-20201117-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+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4887 Comm: systemd-journal Not tainted 5.10.0-rc4-next-20201117-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:unwind_next_frame+0x27/0x1f90 arch/x86/kernel/unwind_orc.c:418 Code: 0f 1f 00 48 b8 00 00 00 00 00 fc ff df 41 57 49 89 ff 41 56 41 55 41 54 55 53 48 81 ec a0 00 00 00 48 c7 44 24 40 b3 8a b5 41 <48> 8d 5c 24 40 48 c7 44 24 48 e1 08 c6 8a 48 c1 eb 03 48 c7 44 24 RSP: 0018:ffffc900015cf988 EFLAGS: 00000286 RAX: dffffc0000000000 RBX: ffffffff815f49d0 RCX: 0000000000000000 RDX: 1ffff920002b9f78 RSI: ffffffff89000068 RDI: ffffc900015cfa60 RBP: ffffc900015cfae8 R08: ffffffff8df685b6 R09: 0000000000000001 R10: 0000000000082081 R11: 0000000000000001 R12: ffffc900015cfb18 R13: 0000000000000000 R14: ffff888025b43500 R15: ffffc900015cfa60 FS: 00007f349340e8c0(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3490917000 CR3: 0000000011405000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:121 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:49 kasan_set_track mm/kasan/common.c:57 [inline] __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:480 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+0x9a/0xe0 include/linux/audit.h:319 getname fs/namei.c:209 [inline] user_path_create fs/namei.c:3525 [inline] do_mkdirat+0x8d/0x2d0 fs/namei.c:3665 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f34926ca687 Code: 00 b8 ff ff ff ff c3 0f 1f 40 00 48 8b 05 09 d8 2b 00 64 c7 00 5f 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 b8 53 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 d7 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffdeca8dc28 EFLAGS: 00000293 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007ffdeca90b40 RCX: 00007f34926ca687 RDX: 00007f349313ba00 RSI: 00000000000001ed RDI: 000055ee128218a0 RBP: 00007ffdeca8dc60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000069 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffdeca90b40 R15: 00007ffdeca8e150