rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P18481/1:b..l rcu: (detected by 0, t=10502 jiffies, g=91257, q=721 ncpus=2) task:dhcpcd-run-hook state:R running task stack:27608 pid:18481 tgid:18481 ppid:18475 task_flags:0x400040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:unwind_next_frame+0x1560/0x20a0 arch/x86/kernel/unwind_orc.c:648 Code: 02 00 0f 84 50 f9 ff ff 4c 89 e7 e8 ca e7 bb 00 e9 43 f9 ff ff 48 ba 00 00 00 00 00 fc ff df 48 8d 79 02 48 89 f8 48 c1 e8 03 <0f> b6 34 10 48 8d 41 03 49 89 c0 49 c1 e8 03 41 0f b6 14 10 49 89 RSP: 0018:ffffc900052d7958 EFLAGS: 00000a02 RAX: 1ffffffff2240408 RBX: 0000000000000001 RCX: ffffffff91202040 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffffffff91202042 RBP: ffffc900052d7a60 R08: ffffffff91202044 R09: 00000000ffffffff R10: 0000000000000002 R11: 0000000000006cdb R12: ffffc900052d7a68 R13: ffffc900052d7a18 R14: ffffc900052d7a18 R15: ffffc900052d7a4c __unwind_start+0x45f/0x7f0 arch/x86/kernel/unwind_orc.c:758 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0x73/0x100 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556 slab_free_hook mm/slub.c:2501 [inline] slab_free mm/slub.c:6663 [inline] kmem_cache_free+0x15e/0x770 mm/slub.c:6774 file_free fs/file_table.c:79 [inline] __fput+0x68d/0xb70 fs/file_table.c:481 fput_close_sync+0x118/0x260 fs/file_table.c:573 __do_sys_close fs/open.c:1573 [inline] __se_sys_close fs/open.c:1558 [inline] __x64_sys_close+0x8b/0x120 fs/open.c:1558 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0e5ce32a67 RSP: 002b:00007ffe09dfe608 EFLAGS: 00000202 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0e5ce32a67 RDX: 000000000000c571 RSI: 0000558f33aeda90 RDI: 0000000000000003 RBP: 0000558f33ae5bc4 R08: 0000000000004530 R09: 0000000000000000 R10: 0000558f33ae5bb9 R11: 0000000000000202 R12: 00007ffe09dfe758 R13: 0000558f33ae5bb8 R14: 0000000000000001 R15: 0000558f33aeca87 rcu: rcu_preempt kthread starved for 10430 jiffies! g91257 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:27944 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 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: 18484 Comm: syz.0.2813 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:__sanitizer_cov_trace_pc+0x5a/0x70 kernel/kcov.c:223 Code: 35 8b 82 6c 16 00 00 85 c0 74 2b 8b 82 48 16 00 00 83 f8 02 75 20 48 8b 8a 50 16 00 00 8b 92 4c 16 00 00 48 8b 01 48 83 c0 01 <48> 39 d0 73 07 48 89 01 48 89 34 c1 e9 c5 3e bb 09 0f 1f 44 00 00 RSP: 0018:ffffc9000478f5f8 EFLAGS: 00000016 RAX: 0000000000080000 RBX: ffffc9000478f738 RCX: ffffc9000f50a000 RDX: 0000000000080000 RSI: ffffffff816e35e3 RDI: 0000000000000005 RBP: ffffffff8df49c5c R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000010 R11: 0000000000000000 R12: ffffc9000478f748 R13: 00000000fff21d11 R14: ffffffff8df49c64 R15: ffffc9000478f7b8 FS: 00007f303ccb96c0(0000) GS:ffff888124a09000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: fffffffffffffffc CR3: 000000007e3ee000 CR4: 00000000003526f0 Call Trace: ex_handler_imm_reg arch/x86/mm/extable.c:206 [inline] fixup_exception+0x7b3/0xf90 arch/x86/mm/extable.c:360 kernelmode_fixup_or_oops.constprop.0+0x6c/0xe0 arch/x86/mm/fault.c:726 __bad_area_nosemaphore+0x38b/0x690 arch/x86/mm/fault.c:783 do_kern_addr_fault+0x5b/0x80 arch/x86/mm/fault.c:1196 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0xb2/0xc0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0010:strncpy_from_kernel_nofault+0xf4/0x260 mm/maccess.c:97 Code: 0f 84 d1 00 00 00 e8 9b 81 c4 ff 4c 89 f6 4c 89 ef e8 a0 7b c4 ff 4d 39 f5 0f 8d b8 00 00 00 4c 89 fb e8 7f 81 c4 ff 45 31 ed <8a> 45 00 48 b9 00 00 00 00 00 fc ff df 41 89 c4 48 89 d8 48 89 da RSP: 0018:ffffc9000478f7e8 EFLAGS: 00010246 RAX: 0000000000080000 RBX: ffffc9000478f848 RCX: ffffc9000f50a000 RDX: 0000000000080000 RSI: ffffffff81fa62f1 RDI: ffff888030d63c94 RBP: fffffffffffffffc R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffff88801bed9448 R12: ffffc9000478f848 R13: 0000000000000000 R14: 0000000000000008 R15: fffffffffffffffc bpf_probe_read_kernel_str_common kernel/trace/bpf_trace.c:264 [inline] ____bpf_probe_read_kernel_str kernel/trace/bpf_trace.c:273 [inline] bpf_probe_read_kernel_str+0x26/0x70 kernel/trace/bpf_trace.c:270 bpf_prog_6c8a88f82979c0f2+0x4b/0x51 bpf_dispatcher_nop_func include/linux/bpf.h:1376 [inline] __bpf_prog_run include/linux/filter.h:723 [inline] bpf_prog_run include/linux/filter.h:730 [inline] bpf_test_run+0x3d2/0xb50 net/bpf/test_run.c:423 bpf_prog_test_run_skb+0x1035/0x31a0 net/bpf/test_run.c:1158 bpf_prog_test_run kernel/bpf/syscall.c:4703 [inline] __sys_bpf+0x1035/0x4980 kernel/bpf/syscall.c:6182 __do_sys_bpf kernel/bpf/syscall.c:6274 [inline] __se_sys_bpf kernel/bpf/syscall.c:6272 [inline] __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:6272 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f303bd8f749 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:00007f303ccb9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f303bfe6180 RCX: 00007f303bd8f749 RDX: 0000000000000050 RSI: 00002000000002c0 RDI: 000000000000000a RBP: 00007f303be13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f303bfe6218 R14: 00007f303bfe6180 R15: 00007ffc7f49a8a8