vkms_vblank_simulate: vblank timer overrun
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6874/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=53617, q=142 ncpus=2)
task:udevd           state:R  running task     stack:24952 pid:6874  tgid:6874  ppid:5184   task_flags:0x400140 flags:0x00080001
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6929
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7256
 irqentry_exit+0x36/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__seqprop_spinlock_sequence include/linux/seqlock.h:227 [inline]
RIP: 0010:__follow_mount_rcu fs/namei.c:1610 [inline]
RIP: 0010:handle_mounts fs/namei.c:1635 [inline]
RIP: 0010:step_into+0xe1b/0x21a0 fs/namei.c:1989
Code: 48 8b 75 08 4c 89 e7 e8 a3 df 5c ff 9c 41 5c 41 81 e4 00 02 00 00 31 ff 4c 89 e6 e8 cf 01 81 ff 58 4d 85 e4 0f 85 00 04 00 00 <e8> 50 06 81 ff 4d 8d 7d 08 4c 89 f8 48 c1 e8 03 42 0f b6 0c 30 4c
RSP: 0018:ffffc900036a78f0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffffc900036a7c20 RCX: ffffffff823c0758
RDX: ffff888034a42480 RSI: ffffffff823c0767 RDI: 0000000000000007
RBP: ffffc900036a79f0 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: ffff8880311271a0 R14: dffffc0000000000 R15: 0000000000000200
 walk_component+0xfc/0x5b0 fs/namei.c:2157
 link_path_walk+0x627/0xe20 fs/namei.c:2519
 path_openat+0x1b0/0x2cb0 fs/namei.c:4130
 do_filp_open+0x20b/0x470 fs/namei.c:4161
 do_sys_openat2+0x11b/0x1d0 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1463
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f895ab15c3a
RSP: 002b:00007ffe9d7985b8 EFLAGS: 00000206 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ffe9d7985f0 RCX: 00007f895ab15c3a
RDX: 0000000000090800 RSI: 00007ffe9d7989f0 RDI: 00000000ffffff9c
RBP: 0000000000000007 R08: 0000561111773860 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000561111520800
R13: 00007ffe9d7991f0 R14: 00007ffe9d798df0 R15: 00007ffe9d7989f0
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10525 jiffies! g53617 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=33792
rcu: rcu_preempt kthread starved for 10526 jiffies! g53617 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:28024 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:7026
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 1296 Comm: aoe_tx0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:98 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:115 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:140 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:172 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:191 [inline]
RIP: 0010:kasan_check_range+0x159/0x1b0 mm/kasan/generic.c:200
Code: 2c 48 89 c2 48 85 c0 75 ad 48 89 da 4c 89 d8 4c 29 da e9 46 ff ff ff 48 85 d2 74 18 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 0a <80> 38 00 74 f2 e9 75 ff ff ff 5b b8 01 00 00 00 5d 41 5c c3 cc cc
RSP: 0018:ffffc90004c0f928 EFLAGS: 00000086
RAX: fffffbfff2103eda RBX: fffffbfff2103edb RCX: ffffffff81c50c3f
RDX: fffffbfff2103edb RSI: 0000000000000008 RDI: ffffffff9081f6d0
RBP: fffffbfff2103eda R08: 0000000000000000 R09: fffffbfff2103eda
R10: ffffffff9081f6d7 R11: 0000000000000001 R12: ffffffff9add7348
R13: 0000000000000003 R14: 0000000000000001 R15: 0000000000000003
FS:  0000000000000000(0000) GS:ffff888124b0a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000fe030 CR3: 000000007d0de000 CR4: 00000000003526f0
DR0: 0000000000001880 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 cpumask_test_cpu include/linux/cpumask.h:646 [inline]
 cpu_online include/linux/cpumask.h:1205 [inline]
 trace_irq_enable.constprop.0+0x2f/0x120 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x26/0x40 kernel/trace/trace_preemptirq.c:73
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
 _raw_spin_unlock_irqrestore+0x52/0x80 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 uart_port_unlock_irqrestore include/linux/serial_core.h:788 [inline]
 uart_port_unlock_deref drivers/tty/serial/serial_core.c:91 [inline]
 uart_port_unlock_deref drivers/tty/serial/serial_core.c:88 [inline]
 uart_write+0x4c1/0xb30 drivers/tty/serial/serial_core.c:626
 handle_tx+0x204/0x630 drivers/net/caif/caif_serial.c:222
 __netdev_start_xmit include/linux/netdevice.h:5248 [inline]
 netdev_start_xmit include/linux/netdevice.h:5257 [inline]
 xmit_one net/core/dev.c:3845 [inline]
 dev_hard_start_xmit+0x97/0x740 net/core/dev.c:3861
 __dev_queue_xmit+0xa46/0x4490 net/core/dev.c:4763
 dev_queue_xmit include/linux/netdevice.h:3365 [inline]
 tx+0xcc/0x190 drivers/block/aoe/aoenet.c:62
 kthread+0x1e4/0x3e0 drivers/block/aoe/aoecmd.c:1241
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>