rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4362/1:b..l (detected by 0, t=10503 jiffies, g=12337, q=159 ncpus=2) task:udevd state:R running task stack:24560 pid:4362 ppid:3638 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:rcu_preempt_read_enter kernel/rcu/tree_plugin.h:379 [inline] RIP: 0010:__rcu_read_lock+0x29/0x50 kernel/rcu/tree_plugin.h:402 Code: 90 53 65 48 8b 1d 57 35 95 7e 48 81 c3 3c 04 00 00 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 11 03 8b 03 3d 00 00 00 40 7d 02 5b c3 0f 0b eb fa 89 d9 80 e1 07 RSP: 0018:ffffc9000479f460 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff88802b415d7c RCX: dffffc0000000000 RDX: 0000000000000000 RSI: ffffffff8adf1180 RDI: 00007f7479cf16c5 RBP: 0000000000000001 R08: 0000000000000004 R09: 000000000000000c R10: dffffc0000000000 R11: fffff520008f3ead R12: ffff88802b415940 R13: 1ffff11005682bd6 R14: 00007f7479cf16c5 R15: 1ffff920008f3eaa rcu_read_lock include/linux/rcupdate.h:789 [inline] is_bpf_text_address+0x1b/0x2a0 kernel/bpf/core.c:735 kernel_text_address+0x9c/0xd0 kernel/extable.c:125 __kernel_text_address+0x9/0x30 kernel/extable.c:79 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323 arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122 save_stack+0x121/0x230 mm/page_owner.c:127 __reset_page_owner+0x51/0x1a0 mm/page_owner.c:148 reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1486 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413 free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3554 release_pages+0x1fa6/0x2220 mm/swap.c:1035 tlb_batch_pages_flush mm/mmu_gather.c:60 [inline] tlb_flush_mmu_free mm/mmu_gather.c:255 [inline] tlb_flush_mmu+0x105/0x220 mm/mmu_gather.c:262 tlb_finish_mmu+0xf5/0x220 mm/mmu_gather.c:394 exit_mmap+0x384/0x960 mm/mmap.c:3262 __mmput+0x118/0x3c0 kernel/fork.c:1205 exit_mm+0x1fe/0x2d0 kernel/exit.c:565 do_exit+0x905/0x2480 kernel/exit.c:867 do_group_exit+0x217/0x2d0 kernel/exit.c:1022 __do_sys_exit_group kernel/exit.c:1033 [inline] __se_sys_exit_group kernel/exit.c:1031 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1031 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f7479cf16c5 RSP: 002b:00007ffc49f73258 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00005606b7dc1840 RCX: 00007f7479cf16c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 00005606b7db7910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc49f732a0 R14: 0000000000000000 R15: 0000000000000000 rcu: rcu_preempt kthread timer wakeup didn't happen for 4381 jiffies! g12337 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=9445 rcu: rcu_preempt kthread starved for 4384 jiffies! g12337 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27736 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742 Code: 48 89 df e8 77 93 9b f7 e9 44 ff ff ff e8 3d 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d a7 ba 4e 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48 RSP: 0018:ffffffff8c807d88 EFLAGS: 000002c6 RAX: 3a1784a910c37d00 RBX: ffffffff8a37f307 RCX: 3a1784a910c37d00 RDX: 0000000000000001 RSI: ffffffff8a8c10a0 RDI: ffffffff8adf11a0 RBP: ffffffff8c807ec0 R08: ffff8880b8e3580b R09: 1ffff110171c6b01 R10: dffffc0000000000 R11: ffffed10171c6b02 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffffff8c8bc740 R15: 1ffffffff1900fbc FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005606b7dc0a38 CR3: 0000000029501000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: default_idle_call+0x84/0xc0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x3a2/0x680 kernel/sched/idle.c:323 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:422 rest_init+0x2dc/0x300 init/main.c:745 arch_call_rest_init+0xa/0xa init/main.c:905 start_kernel+0x493/0x53c init/main.c:1152 secondary_startup_64_no_verify+0xcf/0xdb