INFO: task syz.1.2688:15896 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.2688      state:D stack:27576 pid:15896 tgid:15894 ppid:5843   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:7058
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
 __mutex_lock_common kernel/locking/mutex.c:676 [inline]
 __mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760
 bdev_open+0xa2/0xe40 block/bdev.c:945
 bdev_file_open_by_dev block/bdev.c:1059 [inline]
 bdev_file_open_by_dev+0x182/0x210 block/bdev.c:1034
 setup_bdev_super+0x78/0x730 fs/super.c:1610
 get_tree_bdev_flags+0x363/0x620 fs/super.c:1690
 vfs_get_tree+0x8b/0x340 fs/super.c:1815
 do_new_mount fs/namespace.c:3808 [inline]
 path_mount+0x1513/0x2000 fs/namespace.c:4123
 do_mount fs/namespace.c:4136 [inline]
 __do_sys_mount fs/namespace.c:4347 [inline]
 __se_sys_mount fs/namespace.c:4324 [inline]
 __x64_sys_mount+0x28d/0x310 fs/namespace.c:4324
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f255038ebe9
RSP: 002b:00007f25512bf038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f25505b6090 RCX: 00007f255038ebe9
RDX: 0000200000000040 RSI: 0000200000004a00 RDI: 0000200000000500
RBP: 00007f2550411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000008007 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f25505b6128 R14: 00007f25505b6090 R15: 00007ffef2070098
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
 watchdog+0xf0e/0x1260 kernel/hung_task.c:491
 kthread+0x3c2/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 69 Comm: kworker/u8:4 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:rb_add_augmented_cached include/linux/rbtree_augmented.h:72 [inline]
RIP: 0010:__enqueue_entity+0x1bd/0xb70 kernel/sched/fair.c:853
Code: 28 49 89 f8 49 c1 e8 03 41 80 3c 00 00 0f 85 37 09 00 00 4d 8b 74 24 28 41 b8 01 00 00 00 49 bd 00 00 00 00 00 fc ff df eb 03 <48> 89 c3 48 8d 7b 18 48 89 f8 48 c1 e8 03 42 80 3c 28 00 0f 85 97
RSP: 0018:ffffc9000211f908 EFLAGS: 00000086
RAX: ffff888066ba8090 RBX: ffff888036dec910 RCX: ffff88801db80090
RDX: ffff8880b843a3c0 RSI: ffff8880b843a408 RDI: ffff888036dec928
RBP: ffff888036dec918 R08: 0000000000000000 R09: fffffbfff2156812
R10: ffffffff90ab4097 R11: 0000000000000001 R12: ffff88801db80080
R13: dffffc0000000000 R14: 0000005a5e4b0432 R15: ffff88801db80000
FS:  0000000000000000(0000) GS:ffff8881246bc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ad0391c300 CR3: 000000000e380000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000097 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 put_prev_entity+0x15d/0x2a0 kernel/sched/fair.c:5552
 put_prev_task_fair+0x3c/0x80 kernel/sched/fair.c:8891
 put_prev_set_next_task kernel/sched/sched.h:2474 [inline]
 pick_next_task kernel/sched/core.c:6296 [inline]
 __schedule+0x1652/0x5de0 kernel/sched/core.c:6902
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:7058
 toggle_allocation_gate mm/kfence/core.c:852 [inline]
 toggle_allocation_gate+0x1d9/0x280 mm/kfence/core.c:842
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
vkms_vblank_simulate: vblank timer overrun