rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=319c/1/0x4000000000000000 softirq=22149/22149 fqs=0
	(detected by 1, t=10502 jiffies, g=28293, q=8 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7673 Comm: syz.0.1210 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__lock_acquire+0x37f/0x7c50 kernel/locking/lockdep.c:4983
Code: 48 8d 04 80 48 8b 8c 24 88 00 00 00 4c 8d a4 c1 e0 0a 00 00 48 8d 8c c1 00 0b 00 00 48 89 4c 24 18 48 c1 e9 03 48 89 4c 24 50 <42> 0f b6 04 01 84 c0 0f 85 1f 63 00 00 4c 8b 75 18 b8 00 e0 ff ff
RSP: 0018:ffffc90000007860 EFLAGS: 00000806
RAX: 0000000000000014 RBX: ffffffff96e53290 RCX: 1ffff1100e56a8e4
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff96e53290
RBP: ffffc90000007ab0 R08: dffffc0000000000 R09: 0000000000000001
R10: fffffbfff1c3eee6 R11: 1ffffffff1c3eee5 R12: ffff888072b54700
R13: 0000000000000000 R14: ffff888072b546f8 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f722ff8 CR3: 000000002c72c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
 debug_object_activate+0x6a/0x490 lib/debugobjects.c:698
 debug_hrtimer_activate kernel/time/hrtimer.c:448 [inline]
 debug_activate kernel/time/hrtimer.c:503 [inline]
 enqueue_hrtimer+0x30/0x3f0 kernel/time/hrtimer.c:1105
 __run_hrtimer kernel/time/hrtimer.c:1764 [inline]
 __hrtimer_run_queues+0x68e/0xd60 kernel/time/hrtimer.c:1811
 hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:page_ext_get+0x27f/0x2a0 mm/page_ext.c:165
Code: 00 48 c7 c2 e0 f0 98 8a e8 6e 94 88 ff e8 29 ca 90 ff 48 c7 c7 e0 ab b2 8c 48 89 de e8 ca 66 88 ff 45 31 ff 4c 89 f8 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 e8 24 c2 a5 ff e9 d9 fe ff ff e8 1a c2 a5
RSP: 0018:ffffc90003c67778 EFLAGS: 00000293
RAX: ffff88801b9c8540 RBX: 0000000000000001 RCX: ffff888072b53b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: 00007f608cae3000
R13: 0000000000000180 R14: 0000000001cc8540 R15: ffff88801b9c8540
 page_table_check_clear+0x4a/0x6b0 mm/page_table_check.c:71
 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
 zap_pte_range mm/memory.c:1435 [inline]
 zap_pmd_range mm/memory.c:1574 [inline]
 zap_pud_range mm/memory.c:1603 [inline]
 zap_p4d_range mm/memory.c:1624 [inline]
 unmap_page_range+0x1924/0x2500 mm/memory.c:1645
 unmap_vmas+0x22c/0x330 mm/memory.c:1730
 exit_mmap+0x1cc/0x8e0 mm/mmap.c:3250
 __mmput+0x118/0x3c0 kernel/fork.c:1200
 exit_mm+0x1e6/0x2c0 kernel/exit.c:565
 do_exit+0x8c1/0x2400 kernel/exit.c:867
 do_group_exit+0x217/0x2d0 kernel/exit.c:1022
 __do_sys_exit_group kernel/exit.c:1033 [inline]
 __se_sys_exit_group kernel/exit.c:1031 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1031
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f608d58eec9
Code: Unable to access opcode bytes at 0x7f608d58ee9f.
RSP: 002b:00007ffe0f496a18 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f608d58eec9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe0f496a7c R08: 000000040f496b0f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000000f6
R13: 00000000000927c0 R14: 000000000002b45c R15: 00007ffe0f496ad0
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g28293 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=13631
rcu: rcu_preempt kthread starved for 10502 jiffies! g28293 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
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:27592 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7673 Comm: syz.0.1210 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__lock_acquire+0x103d/0x7c50 kernel/locking/lockdep.c:5044
Code: 41 c1 c6 10 41 31 c6 01 ca 44 89 f3 c1 c3 13 44 29 f1 31 cb 41 01 d6 29 da 41 89 dc 41 c1 c4 04 41 31 d4 48 c7 c0 e8 ab 1f 8e <48> c1 e8 03 42 0f b6 04 00 84 c0 0f 85 b4 5a 00 00 41 01 de 83 3d
RSP: 0018:ffffc900000078e0 EFLAGS: 00000086
RAX: ffffffff8e1fabe8 RBX: 000000009d688036 RCX: 00000000bbbaa21c
RDX: 00000000627eab1d RSI: 00000000000018a2 RDI: ffffffff90ae2248
RBP: ffffc90000007b30 R08: dffffc0000000000 R09: fffffbfff215c44a
R10: fffffbfff215c44a R11: 1ffffffff215c449 R12: 00000000b4f6a874
R13: 0000000000000063 R14: 00000000442c702d R15: ffff888072b546f8
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f722ff8 CR3: 000000002c72c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
 _raw_spin_lock_irq+0x9f/0xe0 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1751 [inline]
 __hrtimer_run_queues+0x63a/0xd60 kernel/time/hrtimer.c:1811
 hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:page_ext_get+0x27f/0x2a0 mm/page_ext.c:165
Code: 00 48 c7 c2 e0 f0 98 8a e8 6e 94 88 ff e8 29 ca 90 ff 48 c7 c7 e0 ab b2 8c 48 89 de e8 ca 66 88 ff 45 31 ff 4c 89 f8 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 e8 24 c2 a5 ff e9 d9 fe ff ff e8 1a c2 a5
RSP: 0018:ffffc90003c67778 EFLAGS: 00000293
RAX: ffff88801b9c8540 RBX: 0000000000000001 RCX: ffff888072b53b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: 00007f608cae3000
R13: 0000000000000180 R14: 0000000001cc8540 R15: ffff88801b9c8540
 page_table_check_clear+0x4a/0x6b0 mm/page_table_check.c:71
 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
 zap_pte_range mm/memory.c:1435 [inline]
 zap_pmd_range mm/memory.c:1574 [inline]
 zap_pud_range mm/memory.c:1603 [inline]
 zap_p4d_range mm/memory.c:1624 [inline]
 unmap_page_range+0x1924/0x2500 mm/memory.c:1645
 unmap_vmas+0x22c/0x330 mm/memory.c:1730
 exit_mmap+0x1cc/0x8e0 mm/mmap.c:3250
 __mmput+0x118/0x3c0 kernel/fork.c:1200
 exit_mm+0x1e6/0x2c0 kernel/exit.c:565
 do_exit+0x8c1/0x2400 kernel/exit.c:867
 do_group_exit+0x217/0x2d0 kernel/exit.c:1022
 __do_sys_exit_group kernel/exit.c:1033 [inline]
 __se_sys_exit_group kernel/exit.c:1031 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1031
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f608d58eec9
Code: Unable to access opcode bytes at 0x7f608d58ee9f.
RSP: 002b:00007ffe0f496a18 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f608d58eec9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe0f496a7c R08: 000000040f496b0f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000000f6
R13: 00000000000927c0 R14: 000000000002b45c R15: 00007ffe0f496ad0
 </TASK>
vkms_vblank_simulate: vblank timer overrun