rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8722 rcu: (detected by 1, t=10502 jiffies, g=22861, q=913 ncpus=2) task:syz.1.475 state:R running task stack:26024 pid:8722 tgid:8721 ppid:5876 task_flags:0x400140 flags:0x00004002 Call Trace: sched_show_task+0x49d/0x630 kernel/sched/core.c:7933 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:292 [inline] print_other_cpu_stall+0xf7a/0x1340 kernel/rcu/tree_stall.h:681 check_cpu_stall kernel/rcu/tree_stall.h:857 [inline] rcu_pending kernel/rcu/tree.c:3671 [inline] rcu_sched_clock_irq+0xa47/0x11b0 kernel/rcu/tree.c:2706 update_process_times+0x23c/0x2f0 kernel/time/timer.c:2473 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x39a/0x520 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x4dd/0xc60 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__sanitizer_cov_trace_pc+0x3c/0x70 kernel/kcov.c:220 Code: 8b 15 08 6a e1 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 3c 16 00 00 00 74 2c 8b 91 18 16 00 00 83 fa 02 75 21 <48> 8b 91 20 16 00 00 48 8b 32 48 8d 7e 01 8b 89 1c 16 00 00 48 39 RSP: 0018:ffffc9001ad2f680 EFLAGS: 00000246 RAX: ffffffff89789b90 RBX: 0000000000000010 RCX: ffff88801ebada00 RDX: 0000000000000002 RSI: 0000000000000040 RDI: 0000000000000017 RBP: 0000000000000010 R08: ffff88802ce1258b R09: 1ffff110059c24b1 R10: dffffc0000000000 R11: ffffed10059c24b2 R12: 0000000000000016 R13: 0000000000000040 R14: 0000000000000007 R15: 0000000000000017 __ptr_ring_discard_one include/linux/ptr_ring.h:272 [inline] __ptr_ring_consume include/linux/ptr_ring.h:301 [inline] page_pool_refill_alloc_cache+0x270/0x7f0 net/core/page_pool.c:400 __page_pool_get_cached net/core/page_pool.c:439 [inline] page_pool_alloc_netmems net/core/page_pool.c:610 [inline] page_pool_alloc_pages+0x129/0x200 net/core/page_pool.c:626 page_pool_dev_alloc_pages include/net/page_pool/helpers.h:96 [inline] xdp_test_run_batch net/bpf/test_run.c:306 [inline] bpf_test_run_xdp_live+0x64b/0x1b20 net/bpf/test_run.c:390 bpf_prog_test_run_xdp+0x713/0x1000 net/bpf/test_run.c:1322 bpf_prog_test_run+0x2c4/0x340 kernel/bpf/syscall.c:4590 __sys_bpf+0x581/0x870 kernel/bpf/syscall.c:6047 __do_sys_bpf kernel/bpf/syscall.c:6139 [inline] __se_sys_bpf kernel/bpf/syscall.c:6137 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6137 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f926458ebe9 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:00007f92654a0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f92647b5fa0 RCX: 00007f926458ebe9 RDX: 0000000000000050 RSI: 0000200000000640 RDI: 000000000000000a RBP: 00007f9264611e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f92647b6038 R14: 00007f92647b5fa0 R15: 00007ffc4ae7d178 rcu: rcu_preempt kthread starved for 10369 jiffies! g22861 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:27560 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 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+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.17.0-rc1-next-20250814-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: cc cc cc cc 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 93 86 0c 00 f3 0f 1e fa fb f4 48 e8 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffffff8de07d80 EFLAGS: 000002c6 RAX: 926cc9e82561e300 RBX: ffffffff81968368 RCX: 926cc9e82561e300 RDX: 0000000000000001 RSI: ffffffff8be34be0 RDI: ffffffff81968368 RBP: ffffffff8de07eb8 R08: ffff8880b8632f9b R09: 1ffff110170c65f3 R10: dffffc0000000000 R11: ffffed10170c65f4 R12: ffffffff8fa3b130 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1bd2a40 FS: 0000000000000000(0000) GS:ffff888125c0f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555b99b608 CR3: 000000007daea000 CR4: 00000000003526f0 Call Trace: 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 rest_init+0x2de/0x300 init/main.c:756 start_kernel+0x3a9/0x410 init/main.c:1109 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x147