rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4461/1:b..l
	(detected by 0, t=10502 jiffies, g=6445, q=402)
task:syz.4.62        state:R  running task     stack:25208 pid: 4461 ppid:  4165 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6549
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6574
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 bpf_test_timer_leave+0x122/0x150 net/bpf/test_run.c:48
 bpf_test_timer_continue+0x25c/0x350 net/bpf/test_run.c:76
 bpf_prog_test_run_flow_dissector+0x53e/0x860 net/bpf/test_run.c:909
 bpf_prog_test_run+0x32f/0x3a0 kernel/bpf/syscall.c:3368
 __sys_bpf+0x3ac/0x670 kernel/bpf/syscall.c:4669
 __do_sys_bpf kernel/bpf/syscall.c:4755 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4753 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4753
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fcb6b95ad29
RSP: 002b:00007fcb697cb038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fcb6bb4afa0 RCX: 00007fcb6b95ad29
RDX: 0000000000000050 RSI: 0000000020000640 RDI: 000000000000000a
RBP: 00007fcb6b9d6aa8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fcb6bb4afa0 R15: 00007ffe4250cea8
 </TASK>
rcu: rcu_preempt kthread starved for 10521 jiffies! g6445 f0x0 RCU_GP_DOING_FQS(6) ->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:27064 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6549
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6574
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
 _raw_spin_unlock_irqrestore+0x128/0x130 kernel/locking/spinlock.c:194
 rcu_gp_fqs_loop+0x67f/0x1080 kernel/rcu/tree.c:1986
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 4446 Comm: syz.0.57 Not tainted 5.15.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: 31 61 f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 1e 65 1a f7 48 89 df e8 76 b9 1b f7 e8 21 75 3e f7 fb bf 01 00 00 00 <e8> 96 fe 0e f7 65 8b 05 a7 e1 b9 75 85 c0 74 02 5b c3 e8 74 fe b7
RSP: 0018:ffffc90002cefbc0 EFLAGS: 00000282
RAX: 72d7dc3f11676800 RBX: ffff88807585e5c0 RCX: ffffffff96a8ff03
RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: 0000000000000001
RBP: 0000000000000000 R08: ffffffff81870360 R09: ffffed100eb0bcb9
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000021
R13: dffffc0000000000 R14: ffff88807585ea58 R15: ffff88807585e5c0
 spin_unlock_irq include/linux/spinlock.h:413 [inline]
 get_signal+0x13ee/0x14e0 kernel/signal.c:2903
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f432b47e710
Code: 10 83 e0 01 83 e2 01 88 15 e2 df e5 00 88 05 df df e5 00 c3 50 48 8d 35 a0 a3 1b 00 48 8d 3d a6 a3 1b 00 31 c0 e8 30 f7 ff ff <53> 89 fb 48 83 ec 10 64 8b 04 25 94 ff ff ff 85 c0 74 2a 89 fe 31
RSP: 002b:00007ffd78e713f8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f432b7ad2d8 RCX: 00007f432b574347
RDX: 00007ffd78e71400 RSI: 00007ffd78e71530 RDI: 0000000000000007
RBP: 00007f432b7ad24c R08: 00007f432b7acfa0 R09: 00007ffd78e71857
R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f432b7ad240 R14: 0000000000000003 R15: 00000000000000e9
 </TASK>