INFO: task syz-executor.4:20358 blocked for more than 143 seconds. Not tainted 5.16.0-rc1-next-20211118-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:27840 pid:20358 ppid: 15860 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:4987 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6268 schedule+0xd2/0x260 kernel/sched/core.c:6341 blk_mq_freeze_queue_wait+0x112/0x160 block/blk-mq.c:178 __loop_clr_fd+0x1ae/0x1070 drivers/block/loop.c:1122 lo_release+0x1ac/0x1f0 drivers/block/loop.c:1761 blkdev_put_whole block/bdev.c:694 [inline] blkdev_put+0x2fb/0x9e0 block/bdev.c:956 deactivate_locked_super+0x94/0x160 fs/super.c:335 deactivate_super+0xad/0xd0 fs/super.c:366 cleanup_mnt+0x3a2/0x540 fs/namespace.c:1137 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xc14/0x2b40 kernel/exit.c:832 do_group_exit+0x125/0x310 kernel/exit.c:929 get_signal+0x34c/0x28b0 kernel/signal.c:2837 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f83a3ea1ae9 RSP: 002b:00007f83a13f6218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f83a3fb5028 RCX: 00007f83a3ea1ae9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f83a3fb5028 RBP: 00007f83a3fb5020 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f83a3fb502c R13: 00007ffefe3e99af R14: 00007f83a13f6300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8bb83ba0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 3 locks held by kworker/u4:4/970: #0: ffff8880b9c39a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:478 #1: ffff8880b9c279c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x173/0x490 kernel/sched/psi.c:871 #2: ffff8880b9c28298 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x5a/0x1f0 kernel/time/timer.c:946 1 lock held by in:imklog/6223: 2 locks held by syz-executor.4/20358: #0: ffff88801ac25918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x97/0x9e0 block/bdev.c:914 #1: ffff88801ac21360 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x7a/0x1070 drivers/block/loop.c:1106 1 lock held by syz-executor.4/23165: #0: ffff88801ac25918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0x9b/0xb50 block/bdev.c:819 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.16.0-rc1-next-20211118-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:254 [inline] watchdog+0xcb7/0xed0 kernel/hung_task.c:339 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 15468 Comm: kworker/u4:2 Not tainted 5.16.0-rc1-next-20211118-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:kasan_check_range+0x16/0x180 mm/kasan/generic.c:188 Code: a8 01 48 0f 45 fa e8 e9 6f ec ff 0f 0b 0f 1f 80 00 00 00 00 48 85 f6 0f 84 3c 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:ffffc90015ec7770 EFLAGS: 00000086 RAX: 0000000000000002 RBX: 0000000000000091 RCX: ffffffff815c685f RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ff72a10 RBP: ffff88807de245d2 R08: 0000000000000000 R09: ffffffff8ff72a18 R10: fffffbfff1fee542 R11: 000000000000003f R12: ffff88807de245b0 R13: ffff88807de23a80 R14: 0000000000000000 R15: f898ddfb375db0ac FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe50fdc1000 CR3: 000000000b88e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] hlock_class kernel/locking/lockdep.c:199 [inline] lookup_chain_cache_add kernel/locking/lockdep.c:3713 [inline] validate_chain kernel/locking/lockdep.c:3769 [inline] __lock_acquire+0x162f/0x54a0 kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:354 [inline] __get_locked_pte+0x2b6/0x4d0 mm/memory.c:1726 get_locked_pte include/linux/mm.h:2160 [inline] __text_poke+0x1ae/0x8c0 arch/x86/kernel/alternative.c:1000 text_poke_bp_batch+0x3d7/0x560 arch/x86/kernel/alternative.c:1361 text_poke_flush arch/x86/kernel/alternative.c:1451 [inline] text_poke_flush arch/x86/kernel/alternative.c:1448 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1458 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d5/0x430 kernel/jump_label.c:830 static_key_disable_cpuslocked+0x152/0x1b0 kernel/jump_label.c:207 static_key_disable+0x16/0x20 kernel/jump_label.c:215 toggle_allocation_gate mm/kfence/core.c:746 [inline] toggle_allocation_gate+0x183/0x390 mm/kfence/core.c:724 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: a8 01 test $0x1,%al 2: 48 0f 45 fa cmovne %rdx,%rdi 6: e8 e9 6f ec ff callq 0xffec6ff4 b: 0f 0b ud2 d: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 14: 48 85 f6 test %rsi,%rsi 17: 0f 84 3c 01 00 00 je 0x159 1d: 49 89 f9 mov %rdi,%r9 20: 41 54 push %r12 22: 44 0f b6 c2 movzbl %dl,%r8d 26: 49 01 f1 add %rsi,%r9 29: 55 push %rbp * 2a: 53 push %rbx <-- trapping instruction 2b: 0f 82 18 01 00 00 jb 0x149 31: 48 b8 ff ff ff ff ff movabs $0xffff7fffffffffff,%rax 38: 7f ff ff 3b: 48 39 c7 cmp %rax,%rdi 3e: 0f .byte 0xf 3f: 86 .byte 0x86