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): P7196/1:b..l
	(detected by 0, t=10502 jiffies, g=31277, q=119 ncpus=2)
task:cmp             state:R  running task     stack:24352 pid:7196  ppid:7159   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6562
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6874
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [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+0x89/0x290 mm/kasan/generic.c:189
Code: 4d 29 ce 49 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 48 f7 d3 4c 01 db 41 80 39 00 0f 85 c1 01 00 00 49 ff c1 48 ff c3 75 ee <e9> 1c 01 00 00 44 89 cb 83 e3 07 0f 84 b5 00 00 00 41 80 39 00 4d
RSP: 0018:ffffc9000e80ef60 EFLAGS: 00000256
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81632999
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8dff2468
RBP: ffffc9000e80f098 R08: dffffc0000000000 R09: fffffbfff1bfe48e
R10: fffffbfff1bfe48e R11: 1ffffffff1bfe48d R12: 0000000000000001
R13: 1ffff92001d01dfc R14: 0000000000000001 R15: dffffc0000000001
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 cpumask_test_cpu include/linux/cpumask.h:444 [inline]
 cpu_online include/linux/cpumask.h:1030 [inline]
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0xd9/0x490 kernel/locking/lockdep.c:5633
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 is_bpf_text_address+0x43/0x2a0 kernel/bpf/core.c:735
 kernel_text_address+0x9c/0xd0 kernel/extable.c:125
 __kernel_text_address+0x9/0x30 kernel/extable.c:79
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383
 mt_alloc_one lib/maple_tree.c:154 [inline]
 mas_alloc_nodes+0x2ec/0x890 lib/maple_tree.c:1279
 mas_node_count_gfp lib/maple_tree.c:1361 [inline]
 mas_node_count lib/maple_tree.c:1375 [inline]
 mas_root_expand+0x208/0xa70 lib/maple_tree.c:3684
 mas_store_gfp+0x2aa/0x3f0 lib/maple_tree.c:5767
 do_mas_align_munmap+0x8c2/0x1220 mm/mmap.c:2508
 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650
 __mmap_region mm/mmap.c:2698 [inline]
 mmap_region+0x6e5/0x1c70 mm/mmap.c:2916
 do_mmap+0x958/0xfd0 mm/mmap.c:1436
 vm_mmap_pgoff+0x1b2/0x2b0 mm/util.c:520
 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fec07580242
RSP: 002b:00007ffcf512f6f8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fec072e2000 RCX: 00007fec07580242
RDX: 0000000000000005 RSI: 000000000014e000 RDI: 00007fec072e2000
RBP: 0000000000000812 R08: 0000000000000003 R09: 0000000000028000
R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffcf512f748
R13: 00007fec0755c5f0 R14: 00007ffcf512ff30 R15: 00000fff9ea25ee2
 </TASK>
rcu: rcu_preempt kthread starved for 10481 jiffies! g31277 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:26880 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:2168
 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7182 Comm: syz.5.537 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__lock_acquire+0x1c5/0x7c50 kernel/locking/lockdep.c:4952
Code: 89 44 24 60 48 c7 c0 40 21 9d 96 48 c1 e8 03 42 0f b6 04 00 84 c0 0f 85 c4 64 00 00 83 3d f2 f0 39 15 00 75 0b 83 7c 24 60 30 <0f> 83 a6 57 00 00 44 89 6c 24 34 4c 89 74 24 40 44 8b 6d 20 48 c7
RSP: 0018:ffffc900001e09c0 EFLAGS: 00000083
RAX: 0000000000000004 RBX: ffffffff8c944808 RCX: ffffffff969d2103
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c944808
RBP: ffffc900001e0c10 R08: dffffc0000000000 R09: 0000000000000001
R10: fffffbfff1bfe48e R11: 1ffffffff1bfe48d R12: ffff88802fc21dc0
R13: 0000000000000001 R14: ffff88802fc22898 R15: ffffffff902567c0
FS:  00007f2d99a1c6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6405c024cb CR3: 0000000073cf1000 CR4: 00000000003506e0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
 seqcount_lockdep_reader_access+0xc6/0x1c0 include/linux/seqlock.h:102
 timekeeping_get_delta kernel/time/timekeeping.c:254 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:388 [inline]
 ktime_get+0x7b/0x270 kernel/time/timekeeping.c:848
 clockevents_program_event+0xe2/0x310 kernel/time/clockevents.c:326
 hrtimer_interrupt+0x59d/0x9c0 kernel/time/hrtimer.c:1886
 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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 de 6c 48 f7 48 89 df e8 36 32 49 f7 e8 d1 27 6c f7 fb bf 01 00 00 00 <e8> f6 a7 3c f7 65 8b 05 27 31 e7 75 85 c0 74 02 5b c3 e8 c4 42 e5
RSP: 0018:ffffc9000e0efb98 EFLAGS: 00000282
RAX: 94e721b576e1f600 RBX: ffff888078111bc0 RCX: 94e721b576e1f600
RDX: dffffc0000000000 RSI: ffffffff8a6c0600 RDI: 0000000000000001
RBP: ffff888078111e58 R08: dffffc0000000000 R09: ffffed100f022379
R10: ffffed100f022379 R11: 1ffff1100f022378 R12: 1ffff1100f0223cb
R13: 0000000000000011 R14: dffffc0000000000 R15: 0000000000000000
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x1163/0x1350 kernel/signal.c:2874
 arch_do_signal_or_restart+0xb7/0x1240 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2d98b8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2d99a1c0e8 EFLAGS: 00000246
RAX: fffffffffffffffc RBX: 00007f2d98de5fa8 RCX: 00007f2d98b8f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2d98de5fa8
RBP: 00007f2d98de5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2d98de6038 R14: 00007ffe9096a580 R15: 00007ffe9096a668
 </TASK>
vkms_vblank_simulate: vblank timer overrun
vkms_vblank_simulate: vblank timer overrun
hrtimer: interrupt took 1278372162 ns
vkms_vblank_simulate: vblank timer overrun