rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10169 rcu: (detected by 0, t=10502 jiffies, g=38501, q=1028 ncpus=2) task:syz.7.899 state:R running task stack:25088 pid:10169 tgid:10166 ppid:9280 task_flags:0x400140 flags:0x00080000 Call Trace: sched_show_task+0x49d/0x630 kernel/sched/core.c:7822 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:856 [inline] rcu_pending kernel/rcu/tree.c:3667 [inline] rcu_sched_clock_irq+0xac1/0x1280 kernel/rcu/tree.c:2704 update_process_times+0x23c/0x2f0 kernel/time/timer.c:2474 tick_sched_handle kernel/time/tick-sched.c:298 [inline] tick_nohz_handler+0x3e9/0x710 kernel/time/tick-sched.c:319 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x4d0/0xc30 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:get_page_from_freelist+0x198/0x2440 mm/page_alloc.c:3770 Code: 48 89 84 24 50 01 00 00 43 8d 04 40 48 89 84 24 38 01 00 00 49 63 c8 48 89 bc 24 48 01 00 00 48 63 c7 48 89 84 24 58 01 00 00 <48> 89 8c 24 40 01 00 00 48 6b c1 68 48 89 84 24 90 00 00 00 45 31 RSP: 0018:ffffc900030c6c80 EFLAGS: 00000a02 RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 0000000000000901 RSI: 00000000000001c0 RDI: 0000000000000001 RBP: ffffc900030c6ef0 R08: 0000000000000000 R09: ffffc900030c6f18 R10: ffffc900030c6f40 R11: fffff52000618ded R12: dffffc0000000000 R13: 1ffff92000618de4 R14: 0000000000052820 R15: ffffc900030c6f48 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3b0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xf2b/0x1960 mm/slub.c:4656 __slab_alloc+0x65/0x100 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5255 [inline] kmem_cache_alloc_noprof+0x40f/0x710 mm/slub.c:5274 skb_clone+0x212/0x3a0 net/core/skbuff.c:2087 dev_queue_xmit_nit+0x29a/0xad0 net/core/dev.c:2556 xmit_one net/core/dev.c:3850 [inline] dev_hard_start_xmit+0x1c1/0x800 net/core/dev.c:3870 __dev_queue_xmit+0x1493/0x3140 net/core/dev.c:4818 dev_queue_xmit include/linux/netdevice.h:3387 [inline] __bpf_tx_skb+0x18e/0x260 net/core/filter.c:2153 ____bpf_clone_redirect net/core/filter.c:2487 [inline] bpf_clone_redirect+0x313/0x4b0 net/core/filter.c:2450 bpf_prog_3e1cbbed0c4acd81+0x5f/0x68 bpf_dispatcher_nop_func include/linux/bpf.h:1378 [inline] __bpf_prog_run include/linux/filter.h:723 [inline] bpf_prog_run include/linux/filter.h:730 [inline] bpf_test_run+0x313/0x7d0 net/bpf/test_run.c:423 bpf_prog_test_run_skb+0xd67/0x1d50 net/bpf/test_run.c:1158 bpf_prog_test_run+0x2c7/0x340 kernel/bpf/syscall.c:4704 __sys_bpf+0x5ee/0x8a0 kernel/bpf/syscall.c:6226 __do_sys_bpf kernel/bpf/syscall.c:6321 [inline] __se_sys_bpf kernel/bpf/syscall.c:6319 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6319 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd20458f749 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:00007fd2054b7038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fd2047e6090 RCX: 00007fd20458f749 RDX: 0000000000000050 RSI: 0000200000001080 RDI: 000000000000000a RBP: 00007fd204613f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd2047e6128 R14: 00007fd2047e6090 R15: 00007ffd07091a38 rcu: rcu_preempt kthread starved for 10295 jiffies! g38501 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:27296 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5258 [inline] __schedule+0x150e/0x5070 kernel/sched/core.c:6866 __schedule_loop kernel/sched/core.c:6948 [inline] schedule+0x165/0x360 kernel/sched/core.c:6963 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+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 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 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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 33 9e 2a 00 f3 0f 1e fa fb f4 48 ee 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0000:ffffc90000197de0 EFLAGS: 000002c6 RAX: 1a1fefbeeb180700 RBX: ffffffff819786ba RCX: 1a1fefbeeb180700 RDX: 0000000000000001 RSI: ffffffff8d997e54 RDI: ffffffff8be07960 RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8fa22f70 R13: 1ffff11003b56b70 R14: 0000000000000001 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125d25000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fded292695a CR3: 00000000227c2000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1ea/0x520 kernel/sched/idle.c:332 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x147