rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (10499 ticks this GP) idle=1c14/1/0x4000000000000000 softirq=16555/16562 fqs=6 rcu: hardirqs softirqs csw/system rcu: number: 388023 34 0 rcu: cputime: 7504 2359 3 ==> 9870(ms) rcu: (t=10500 jiffies g=17905 q=1102 ncpus=2) rcu: rcu_preempt kthread starved for 974 jiffies! g17905 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:26888 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 schedule_timeout+0x160/0x280 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 6484 Comm: syz.5.135 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:__sanitizer_cov_trace_switch+0x81/0x120 kernel/kcov.c:349 Code: 00 00 00 b9 01 00 00 00 48 85 c0 0f 84 ae 00 00 00 41 57 41 56 41 54 53 48 8b 54 24 20 65 4c 8b 05 84 24 7e 7e 45 31 c9 eb 08 <49> ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d 72 24 7e 7e 41 RSP: 0018:ffffc90000007390 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffffffff8f6dcbb4 RCX: 0000000000000003 RDX: ffffffff813aa915 RSI: ffffffff8cb9e740 RDI: 0000000000000002 RBP: ffffc900000074d8 R08: ffff88804b260000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000100 R12: ffffc90000007488 R13: dffffc0000000000 R14: 0000000000000002 R15: ffffffff8f6dcbb9 FS: 00007f23659be6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbf350a8440 CR3: 000000004cd3d000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: unwind_next_frame+0x655/0x2970 arch/x86/kernel/unwind_orc.c:505 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] kmem_cache_free+0xf8/0x280 mm/slub.c:3852 kfree_skb include/linux/skbuff.h:1232 [inline] ip6_mc_input+0xa7e/0xc70 net/ipv6/ip6_input.c:589 NF_HOOK+0x303/0x390 include/linux/netfilter.h:304 __netif_receive_skb_one_core net/core/dev.c:5608 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5722 process_backlog+0x380/0x6e0 net/core/dev.c:6050 __napi_poll+0xc0/0x460 net/core/dev.c:6612 napi_poll net/core/dev.c:6679 [inline] net_rx_action+0x5ea/0xbf0 net/core/dev.c:6815 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:preempt_schedule_irq+0xb0/0x140 kernel/sched/core.c:7009 Code: 44 24 20 f6 44 24 21 02 74 0b 0f 0b 48 f7 03 08 00 00 00 74 63 bf 01 00 00 00 e8 8b 09 e5 f6 e8 16 93 15 f7 fb bf 01 00 00 00 db b5 ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24 RSP: 0018:ffffc90003797760 EFLAGS: 00000286 RAX: 6c2ef433b31efa00 RBX: 0000000000000000 RCX: 6c2ef433b31efa00 RDX: dffffc0000000000 RSI: ffffffff8aaabca0 RDI: 0000000000000001 RBP: ffffc90003797800 R08: ffffffff8e4a94ef R09: 1ffffffff1c9529d R10: dffffc0000000000 R11: fffffbfff1c9529e R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920006f2eec irqentry_exit+0x67/0x70 kernel/entry/common.c:438 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:seqcount_lockdep_reader_access+0x12a/0x180 include/linux/seqlock.h:105 Code: 55 ba ff 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 47 41 f7 c5 00 02 00 00 74 01 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 66 43 c7 44 27 09 00 00 43 c6 44 27 0b 00 RSP: 0018:ffffc900037978c0 EFLAGS: 00000206 RAX: 6c2ef433b31efa00 RBX: ffff88813fffa7c8 RCX: 6c2ef433b31efa00 RDX: dffffc0000000000 RSI: ffffffff8aaabca0 RDI: ffffffff8afc72c0 RBP: ffffc90003797980 R08: ffffffff8e4a94ef R09: 1ffffffff1c9529d R10: dffffc0000000000 R11: fffffbfff1c9529e R12: dffffc0000000000 R13: 0000000000000a06 R14: ffffffff81d19b2f R15: 1ffff920006f2f18 read_seqbegin include/linux/seqlock.h:893 [inline] zone_span_seqbegin include/linux/memory_hotplug.h:134 [inline] page_outside_zone_boundaries mm/page_alloc.c:448 [inline] bad_range+0x5f/0x280 mm/page_alloc.c:467 rmqueue mm/page_alloc.c:2818 [inline] get_page_from_freelist+0x193b/0x19f0 mm/page_alloc.c:3188 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 __alloc_pages_node include/linux/gfp.h:237 [inline] alloc_pages_node include/linux/gfp.h:260 [inline] bpf_ringbuf_area_alloc kernel/bpf/ringbuf.c:124 [inline] bpf_ringbuf_alloc+0x251/0x560 kernel/bpf/ringbuf.c:172 ringbuf_map_alloc+0x1c3/0x2f0 kernel/bpf/ringbuf.c:207 map_create+0x877/0x12f0 kernel/bpf/syscall.c:1247 __sys_bpf+0x5f0/0x800 kernel/bpf/syscall.c:5455 __do_sys_bpf kernel/bpf/syscall.c:5577 [inline] __se_sys_bpf kernel/bpf/syscall.c:5575 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5575 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f2364b8eba9 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:00007f23659be038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f2364dd5fa0 RCX: 00007f2364b8eba9 RDX: 0000000000000050 RSI: 00002000000001c0 RDI: 0000000000000000 RBP: 00007f2364c11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2364dd6038 R14: 00007f2364dd5fa0 R15: 00007ffc44838b18 CPU: 0 PID: 6484 Comm: syz.5.135 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:__sanitizer_cov_trace_switch+0x81/0x120 kernel/kcov.c:349 Code: 00 00 00 b9 01 00 00 00 48 85 c0 0f 84 ae 00 00 00 41 57 41 56 41 54 53 48 8b 54 24 20 65 4c 8b 05 84 24 7e 7e 45 31 c9 eb 08 <49> ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d 72 24 7e 7e 41 RSP: 0018:ffffc90000007390 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffffffff8f6dcbb4 RCX: 0000000000000003 RDX: ffffffff813aa915 RSI: ffffffff8cb9e740 RDI: 0000000000000002 RBP: ffffc900000074d8 R08: ffff88804b260000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000100 R12: ffffc90000007488 R13: dffffc0000000000 R14: 0000000000000002 R15: ffffffff8f6dcbb9 FS: 00007f23659be6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbf350a8440 CR3: 000000004cd3d000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: unwind_next_frame+0x655/0x2970 arch/x86/kernel/unwind_orc.c:505 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] kmem_cache_free+0xf8/0x280 mm/slub.c:3852 kfree_skb include/linux/skbuff.h:1232 [inline] ip6_mc_input+0xa7e/0xc70 net/ipv6/ip6_input.c:589 NF_HOOK+0x303/0x390 include/linux/netfilter.h:304 __netif_receive_skb_one_core net/core/dev.c:5608 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5722 process_backlog+0x380/0x6e0 net/core/dev.c:6050 __napi_poll+0xc0/0x460 net/core/dev.c:6612 napi_poll net/core/dev.c:6679 [inline] net_rx_action+0x5ea/0xbf0 net/core/dev.c:6815 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:preempt_schedule_irq+0xb0/0x140 kernel/sched/core.c:7009 Code: 44 24 20 f6 44 24 21 02 74 0b 0f 0b 48 f7 03 08 00 00 00 74 63 bf 01 00 00 00 e8 8b 09 e5 f6 e8 16 93 15 f7 fb bf 01 00 00 00 db b5 ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24 RSP: 0018:ffffc90003797760 EFLAGS: 00000286 RAX: 6c2ef433b31efa00 RBX: 0000000000000000 RCX: 6c2ef433b31efa00 RDX: dffffc0000000000 RSI: ffffffff8aaabca0 RDI: 0000000000000001 RBP: ffffc90003797800 R08: ffffffff8e4a94ef R09: 1ffffffff1c9529d R10: dffffc0000000000 R11: fffffbfff1c9529e R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920006f2eec irqentry_exit+0x67/0x70 kernel/entry/common.c:438 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:seqcount_lockdep_reader_access+0x12a/0x180 include/linux/seqlock.h:105 Code: 55 ba ff 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 47 41 f7 c5 00 02 00 00 74 01 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 66 43 c7 44 27 09 00 00 43 c6 44 27 0b 00 RSP: 0018:ffffc900037978c0 EFLAGS: 00000206 RAX: 6c2ef433b31efa00 RBX: ffff88813fffa7c8 RCX: 6c2ef433b31efa00 RDX: dffffc0000000000 RSI: ffffffff8aaabca0 RDI: ffffffff8afc72c0 RBP: ffffc90003797980 R08: ffffffff8e4a94ef R09: 1ffffffff1c9529d R10: dffffc0000000000 R11: fffffbfff1c9529e R12: dffffc0000000000 R13: 0000000000000a06 R14: ffffffff81d19b2f R15: 1ffff920006f2f18 read_seqbegin include/linux/seqlock.h:893 [inline] zone_span_seqbegin include/linux/memory_hotplug.h:134 [inline] page_outside_zone_boundaries mm/page_alloc.c:448 [inline] bad_range+0x5f/0x280 mm/page_alloc.c:467 rmqueue mm/page_alloc.c:2818 [inline] get_page_from_freelist+0x193b/0x19f0 mm/page_alloc.c:3188 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 __alloc_pages_node include/linux/gfp.h:237 [inline] alloc_pages_node include/linux/gfp.h:260 [inline] bpf_ringbuf_area_alloc kernel/bpf/ringbuf.c:124 [inline] bpf_ringbuf_alloc+0x251/0x560 kernel/bpf/ringbuf.c:172 ringbuf_map_alloc+0x1c3/0x2f0 kernel/bpf/ringbuf.c:207 map_create+0x877/0x12f0 kernel/bpf/syscall.c:1247 __sys_bpf+0x5f0/0x800 kernel/bpf/syscall.c:5455 __do_sys_bpf kernel/bpf/syscall.c:5577 [inline] __se_sys_bpf kernel/bpf/syscall.c:5575 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5575 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f2364b8eba9 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:00007f23659be038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f2364dd5fa0 RCX: 00007f2364b8eba9 RDX: 0000000000000050 RSI: 00002000000001c0 RDI: 0000000000000000 RBP: 00007f2364c11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2364dd6038 R14: 00007f2364dd5fa0 R15: 00007ffc44838b18