INFO: task syz-executor.0:14219 blocked for more than 143 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:27968 pid:14219 ppid: 6242 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 blk_mq_freeze_queue_wait+0x112/0x160 block/blk-mq.c:178 loop_set_status+0x17d/0x930 drivers/block/loop.c:1264 loop_set_status_old+0x148/0x1b0 drivers/block/loop.c:1396 lo_ioctl+0x3e9/0x17c0 drivers/block/loop.c:1566 blkdev_ioctl+0x37a/0x800 block/ioctl.c:609 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fd323b66ae9 RSP: 002b:00007fd3210bb188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd323c7a020 RCX: 00007fd323b66ae9 RDX: 0000000020000780 RSI: 0000000000004c02 RDI: 0000000000000003 RBP: 00007fd323bc0f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd3241adb2f R14: 00007fd3210bb300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8bb83b60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 1 lock held by in:imklog/6222: 2 locks held by kworker/u4:2/8983: #0: ffffffff8bb83b60 (rcu_read_lock){....}-{1:2}, 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 1 lock held by syz-executor.0/14219: #0: ffff88801a862360 (&lo->lo_mutex){+.+.}-{3:3}, at: loop_set_status+0x2a/0x930 drivers/block/loop.c:1248 2 locks held by systemd-udevd/14225: #0: ffff88801a866918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0x9b/0xb50 block/bdev.c:819 #1: ffff88801a862360 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_open+0x75/0x120 drivers/block/loop.c:1733 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.0-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:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:295 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: 19936 Comm: kworker/u4:8 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:87 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [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_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0xd2/0x180 mm/kasan/generic.c:189 Code: 48 83 c0 01 48 39 d0 74 7a 80 38 00 74 f2 48 89 c2 b8 01 00 00 00 48 85 d2 75 56 5b 5d 41 5c c3 48 85 d2 74 5e 48 01 ea eb 09 <48> 83 c0 01 48 39 d0 74 50 80 38 00 74 f2 eb d4 41 bc 08 00 00 00 RSP: 0018:ffffc9000295f900 EFLAGS: 00000246 RAX: fffffbfff1b22e62 RBX: fffffbfff1b22e63 RCX: ffffffff815d0308 RDX: fffffbfff1b22e63 RSI: 0000000000000008 RDI: ffffffff8d917310 RBP: fffffbfff1b22e62 R08: 0000000000000000 R09: ffffffff8d917317 R10: fffffbfff1b22e62 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8ba4d6a8 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f16f04b1000 CR3: 000000000b88e000 CR4: 00000000003526f0 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] cpumask_test_cpu include/linux/cpumask.h:344 [inline] cpu_online include/linux/cpumask.h:895 [inline] trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0xb8/0x510 kernel/locking/lockdep.c:5608 __mutex_lock_common kernel/locking/mutex.c:607 [inline] __mutex_lock+0x12f/0x12f0 kernel/locking/mutex.c:740 arch_jump_label_transform_queue+0x58/0x100 arch/x86/kernel/jump_label.c:136 __jump_label_update+0x12e/0x400 kernel/jump_label.c:451 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: 48 83 c0 01 add $0x1,%rax 4: 48 39 d0 cmp %rdx,%rax 7: 74 7a je 0x83 9: 80 38 00 cmpb $0x0,(%rax) c: 74 f2 je 0x0 e: 48 89 c2 mov %rax,%rdx 11: b8 01 00 00 00 mov $0x1,%eax 16: 48 85 d2 test %rdx,%rdx 19: 75 56 jne 0x71 1b: 5b pop %rbx 1c: 5d pop %rbp 1d: 41 5c pop %r12 1f: c3 retq 20: 48 85 d2 test %rdx,%rdx 23: 74 5e je 0x83 25: 48 01 ea add %rbp,%rdx 28: eb 09 jmp 0x33 * 2a: 48 83 c0 01 add $0x1,%rax <-- trapping instruction 2e: 48 39 d0 cmp %rdx,%rax 31: 74 50 je 0x83 33: 80 38 00 cmpb $0x0,(%rax) 36: 74 f2 je 0x2a 38: eb d4 jmp 0xe 3a: 41 bc 08 00 00 00 mov $0x8,%r12d