rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6773/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=16313, q=617217 ncpus=2)
task:syz.4.190       state:R  running task     stack:26344 pid:6773  tgid:6771  ppid:5880   task_flags:0x40054c flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:page_ext_next include/linux/page_ext.h:108 [inline]
RIP: 0010:page_ext_iter_next include/linux/page_ext.h:156 [inline]
RIP: 0010:__update_page_owner_free_handle+0x2be/0x470 mm/page_owner.c:272
Code: f8 48 25 ff 7f 00 00 74 32 e8 ae 2f 93 ff 48 8b 44 24 18 80 3c 18 00 74 0c 48 c7 c7 60 de b2 99 e8 b7 9d f6 ff 4c 8b 7c 24 38 <4c> 03 3d db 5f 86 17 4d 85 ff 75 1e e9 f0 00 00 00 e8 7c 2f 93 ff
RSP: 0018:ffffc9001ccaf808 EFLAGS: 00000246
RAX: 1ffffffff3365bcc RBX: dffffc0000000000 RCX: ffff88807c9d5a00
RDX: 0000000000000000 RSI: 0000000000001673 RDI: 0000000000000000
RBP: ffff88801d8703e4 R08: ffff88801d8703a7 R09: 1ffff11003b0e074
R10: dffffc0000000000 R11: ffffed1003b0e075 R12: 0000000000061673
R13: 0000000000001a75 R14: 0000000000000000 R15: ffff88801d8703a0
 __reset_page_owner+0x85/0x1f0 mm/page_owner.c:309
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
 vfree+0x25a/0x400 mm/vmalloc.c:3434
 kcov_put kernel/kcov.c:439 [inline]
 kcov_close+0x28/0x50 kernel/kcov.c:535
 __fput+0x44c/0xa70 fs/file_table.c:468
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x6b5/0x2300 kernel/exit.c:961
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
 get_signal+0x1286/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3810b8ebe9
RSP: 002b:00007f3811a8a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: 0000000000018ff8 RBX: 00007f3810dc5fa0 RCX: 00007f3810b8ebe9
RDX: 0000000000018ff8 RSI: 0000200000019680 RDI: 0000000000000006
RBP: 00007f3810c11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3810dc6038 R14: 00007f3810dc5fa0 R15: 00007ffedf343638
 </TASK>
rcu: rcu_preempt kthread starved for 1479 jiffies! g16313 f0x2 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:27432 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x8/0x90 kernel/kcov.c:314
Code: 48 89 44 11 20 e9 d3 8e 50 ff cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 14 25 08 80 a0 92 65 8b 0d c8 cd e0 10 81 e1 00 01 ff 00
RSP: 0018:ffffc90000157930 EFLAGS: 00000202
RAX: ffffffff81ad0e0c RBX: ffffc90000157aa0 RCX: 0000000000000000
RDX: ffff88801cebda00 RSI: 0000000000000001 RDI: 0000000000000008
RBP: ffffc90000157a50 R08: ffffffff8fa39037 R09: 1ffffffff1f47206
R10: dffffc0000000000 R11: fffffbfff1f47207 R12: 1ffff9200002af54
R13: 000000000fc00001 R14: 0000000000000001 R15: 0000000000000000
 get_timer_cpu_base kernel/time/timer.c:925 [inline]
 get_timer_base kernel/time/timer.c:944 [inline]
 lock_timer_base kernel/time/timer.c:1003 [inline]
 __try_to_del_timer_sync+0x8c/0x3a0 kernel/time/timer.c:1459
 __timer_delete_sync+0x1fe/0x2d0 kernel/time/timer.c:1620
 schedule_timeout+0x133/0x270 kernel/time/sleep_timeout.c:100
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 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: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 3e 7d 96 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 73 67 0e 00 f3 0f 1e fa fb f4 <e9> 13 7d 96 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c2
RAX: 6c6b1e2657916d00 RBX: ffffffff819683c8 RCX: 6c6b1e2657916d00
RDX: 0000000000000001 RSI: ffffffff8d9b8241 RDI: ffffffff8be33880
RBP: ffffc90000197f20 R08: ffff8880b8732f9b R09: 1ffff110170e65f3
R10: dffffc0000000000 R11: ffffed10170e65f4 R12: ffffffff8fa39030
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110039d9b40
FS:  0000000000000000(0000) GS:ffff888125d18000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000b4030 CR3: 000000007be08000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:757
 default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:190 [inline]
 do_idle+0x1e8/0x510 kernel/sched/idle.c:330
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
 common_startup_64+0x13e/0x147
 </TASK>