vkms_vblank_simulate: vblank timer overrun
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=71ac/1/0x4000000000000000 softirq=101538/101540 fqs=3
(detected by 0, t=10502 jiffies, g=132157, q=125 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 20979 Comm: syz.5.5347 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline]
RIP: 0010:mark_lock+0x9c/0x320 kernel/locking/lockdep.c:4606
Code: 89 c7 41 81 e7 ff 1f 00 00 c1 e8 03 25 f8 03 00 00 48 8d b8 40 12 ae 90 be 08 00 00 00 e8 4c 43 6d 00 4c 0f a3 3d 84 67 4a 0f <73> 10 4b 8d 04 7f c1 e0 06 4c 8d b8 00 91 46 90 eb 24 48 c7 c0 40
RSP: 0018:ffffc900001e0880 EFLAGS: 00000057
RAX: 0000000000000101 RBX: ffff88801f263b80 RCX: ffffffff8163aab4
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90ae1430
RBP: 0000000000000008 R08: dffffc0000000000 R09: fffffbfff215c287
R10: fffffbfff215c287 R11: 1ffffffff215c286 R12: 0000000000000100
R13: dffffc0000000000 R14: ffff88801f264688 R15: 0000000000000f8a
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000240 CR3: 0000000058339000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
mark_usage kernel/locking/lockdep.c:4549 [inline]
__lock_acquire+0xd6f/0x7c50 kernel/locking/lockdep.c:5003
lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
advance_sched+0x47/0x970 net/sched/sch_taprio.c:700
__run_hrtimer kernel/time/hrtimer.c:1752 [inline]
__hrtimer_run_queues+0x554/0xd60 kernel/time/hrtimer.c:1816
hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1878
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
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:size_mul include/linux/overflow.h:144 [inline]
RIP: 0010:hash_stack lib/stackdepot.c:277 [inline]
RIP: 0010:__stack_depot_save+0x50/0x460 lib/stackdepot.c:444
Code: 28 48 c7 44 24 20 00 00 00 00 e8 0b 87 41 fd 41 89 c7 31 c0 45 85 ff 0f 84 51 01 00 00 80 3d 07 fc c6 12 00 0f 85 44 01 00 00 <43> 8d 3c 3f 42 8d 2c fd 7b 71 f5 75 83 ff 04 72 7c 89 e9 89 ea 4c
RSP: 0018:ffffc90004db7278 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000801
RDX: 0000000000000001 RSI: 0000000000000013 RDI: ffffc90004db72e0
RBP: ffffc90004db7508 R08: 0000000000000001 R09: fffffbfff1c3ee26
R10: fffffbfff1c3ee26 R11: 1ffffffff1c3ee25 R12: 0000000000000800
R13: 0000000000000001 R14: ffffc90004db72e0 R15: 0000000000000013
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x60/0x70 mm/kasan/common.c:52
kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1724 [inline]
slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1750
slab_free mm/slub.c:3661 [inline]
kmem_cache_free+0xf7/0x290 mm/slub.c:3683
anon_vma_chain_free mm/rmap.c:146 [inline]
unlink_anon_vmas+0x60e/0x660 mm/rmap.c:446
free_pgtables+0x24e/0x3d0 mm/memory.c:430
exit_mmap+0x33b/0x8e0 mm/mmap.c:3260
__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
get_signal+0x1272/0x1350 kernel/signal.c:2871
arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xb1/0x140 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:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8f2af8ebe9
Code: Unable to access opcode bytes at 0x7f8f2af8ebbf.
RSP: 002b:00007f8f2bd3f0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f8f2b1c5fa8 RCX: 00007f8f2af8ebe9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f8f2b1c5fac
RBP: 00007f8f2b1c5fa0 R08: 00178aa52858cb33 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8f2b1c6038 R14: 00007fffe9089530 R15: 00007fffe9089618
rcu: rcu_preempt kthread starved for 10494 jiffies! g132157 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27040 pid:16 ppid:2 flags:0x00004000
Call Trace:
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
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 21018 Comm: syz.6.5358 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0xe7b/0x1270 kernel/smp.c:998
Code: 00 00 00 41 8b 1f 89 de 83 e6 01 31 ff e8 5d d9 0a 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 e9 d5 0a 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 ce d5 0a
RSP: 0018:ffffc900053f7420 EFLAGS: 00000293
RAX: ffffffff8175fa52 RBX: dffffc0000000000 RCX: ffff888025085940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900053f7580 R08: dffffc0000000000 R09: ffffed10171c776b
R10: ffffed10171c776b R11: 1ffff110171c776a R12: 1ffff110171e81c1
R13: ffff8880b8e3bb40 R14: 0000000000000001 R15: ffff8880b8f40e08
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9dd83de000 CR3: 0000000027d17000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
__flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:970 [inline]
flush_tlb_mm_range+0x409/0x610 arch/x86/mm/tlb.c:1058
tlb_flush arch/x86/include/asm/tlb.h:20 [inline]
tlb_flush_mmu_tlbonly+0x1b1/0x3f0 include/asm-generic/tlb.h:430
tlb_flush_mmu+0x28/0x210 mm/mmu_gather.c:260
tlb_finish_mmu+0xbd/0x1c0 mm/mmu_gather.c:361
exit_mmap+0x343/0x8e0 mm/mmap.c:3262
__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
get_signal+0x1272/0x1350 kernel/signal.c:2871
arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xb1/0x140 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:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f4030f8ebe9
Code: Unable to access opcode bytes at 0x7f4030f8ebbf.
RSP: 002b:00007f4031d6e0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f40311c5fa8 RCX: 00007f4030f8ebe9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f40311c5fac
RBP: 00007f40311c5fa0 R08: 0027f6b0ed91ee94 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f40311c6038 R14: 00007ffd1a8a7ef0 R15: 00007ffd1a8a7fd8
vkms_vblank_simulate: vblank timer overrun