rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8117/1:b..l P8156/1:b..l rcu: (detected by 1, t=10503 jiffies, g=34569, q=1085 ncpus=2) task:dhcpcd-run-hook state:R running task stack:27272 pid:8156 tgid:8156 ppid:8154 task_flags:0x400040 flags:0x00080800 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7513 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x205/0x970 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x5e/0x370 kernel/locking/lockdep.c:5872 Code: 05 fb 03 25 12 83 f8 07 0f 87 d9 02 00 00 48 0f a3 05 06 8d f2 0e 0f 82 a4 02 00 00 8b 35 8e c0 f2 0e 85 f6 0f 85 bf 00 00 00 <48> 8b 44 24 30 65 48 2b 05 9d 03 25 12 0f 85 ed 02 00 00 48 83 c4 RSP: 0018:ffffc90003cd7288 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000003 RDX: 0000000000000000 RSI: ffffffff8deea8c4 RDI: ffffffff8c1c4780 RBP: ffffffff8e7e5560 R08: 00000000693872e6 R09: 0000000000000007 R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] __update_page_owner_free_handle.isra.0+0x4d/0x4d0 mm/page_owner.c:283 __reset_page_owner+0x93/0x190 mm/page_owner.c:321 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1397 [inline] free_unref_folios+0xa44/0x1730 mm/page_alloc.c:2999 folios_put_refs+0x571/0xa90 mm/swap.c:1008 free_pages_and_swap_cache+0x30b/0x3b0 mm/swap_state.c:404 __tlb_batch_free_encoded_pages+0xe9/0x280 mm/mmu_gather.c:138 tlb_batch_pages_flush mm/mmu_gather.c:151 [inline] tlb_flush_mmu_free mm/mmu_gather.c:417 [inline] tlb_flush_mmu mm/mmu_gather.c:424 [inline] tlb_finish_mmu+0x1b0/0x810 mm/mmu_gather.c:549 exit_mmap+0x454/0xa10 mm/mmap.c:1313 __mmput+0x12a/0x410 kernel/fork.c:1178 mmput+0x67/0x80 kernel/fork.c:1201 exec_mmap fs/exec.c:893 [inline] begin_new_exec+0x10f0/0x3880 fs/exec.c:1148 load_elf_binary+0x8f1/0x51b0 fs/binfmt_elf.c:1010 search_binary_handler fs/exec.c:1664 [inline] exec_binprm fs/exec.c:1696 [inline] bprm_execve fs/exec.c:1748 [inline] bprm_execve+0x8f5/0x1740 fs/exec.c:1724 do_execveat_common.isra.0+0x4a5/0x580 fs/exec.c:1846 __do_sys_execve fs/exec.c:1930 [inline] __se_sys_execve fs/exec.c:1924 [inline] __x64_sys_execve+0x93/0xd0 fs/exec.c:1924 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd3e92ac107 RSP: 002b:00007fff5be694d8 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 000056044db6de40 RCX: 00007fd3e92ac107 RDX: 000056044db6de68 RSI: 000056044db6de40 RDI: 000056044db6def8 RBP: 000056044db6def8 R08: 00007fff5be6de44 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 000056044db6de68 R13: 00007fd3e9471e8b R14: 000056044db6de68 R15: 0000000000000000 task:syz.2.344 state:R running task stack:25800 pid:8117 tgid:8115 ppid:7489 task_flags:0x40054c flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7513 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x205/0x970 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:cpu_max_bits_warn include/linux/cpumask.h:138 [inline] RIP: 0010:cpumask_check include/linux/cpumask.h:145 [inline] RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:649 [inline] RIP: 0010:cpu_online include/linux/cpumask.h:1231 [inline] RIP: 0010:trace_lock_release include/trace/events/lock.h:69 [inline] RIP: 0010:lock_release+0x2f/0x310 kernel/locking/lockdep.c:5879 Code: 57 41 56 41 54 55 53 48 89 fb 48 83 ec 18 65 48 8b 2d 7d fe 24 12 48 89 6c 24 10 48 89 f5 0f 1f 44 00 00 65 8b 05 95 fe 24 12 <83> f8 07 0f 87 63 02 00 00 48 0f a3 05 a0 87 f2 0e 0f 82 fa 01 00 RSP: 0018:ffffc90003b5ee90 EFLAGS: 00000286 RAX: 0000000000000001 RBX: ffffffff8e7e5560 RCX: ffffffff9186cd01 RDX: 0000000000000000 RSI: ffffffff81b7d1ae RDI: ffffffff8e7e5560 RBP: ffffffff81b7d1ae R08: 0000000000000001 R09: 0000000000000007 R10: 0000000000000200 R11: 0000000000019052 R12: ffffc90003b5ef98 R13: ffffc90003b5ef48 R14: ffffc90003b5f9d8 R15: ffffc90003b5ef7c rcu_lock_release include/linux/rcupdate.h:310 [inline] rcu_read_unlock include/linux/rcupdate.h:869 [inline] class_rcu_destructor include/linux/rcupdate.h:1181 [inline] unwind_next_frame+0x3c3/0x2090 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 save_stack+0x162/0x1e0 mm/page_owner.c:165 __reset_page_owner+0x84/0x190 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1397 [inline] free_unref_folios+0xa44/0x1730 mm/page_alloc.c:2999 folios_put_refs+0x571/0xa90 mm/swap.c:1008 folio_batch_release include/linux/folio_batch.h:101 [inline] shmem_undo_range+0x5e5/0x1570 mm/shmem.c:1149 shmem_truncate_range mm/shmem.c:1277 [inline] shmem_evict_inode+0x3f3/0xc40 mm/shmem.c:1407 evict+0x3c2/0xad0 fs/inode.c:841 iput_final fs/inode.c:1960 [inline] iput.part.0+0x605/0xf50 fs/inode.c:2009 iput+0x35/0x40 fs/inode.c:1975 dentry_unlink_inode+0x2c0/0x4c0 fs/dcache.c:476 __dentry_kill+0x1d0/0x690 fs/dcache.c:718 finish_dput+0x76/0x480 fs/dcache.c:927 dput.part.0+0x456/0x570 fs/dcache.c:976 dput+0x1f/0x30 fs/dcache.c:968 __fput+0x519/0xb50 fs/file_table.c:518 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x951/0x2af0 kernel/exit.c:976 do_group_exit+0xd5/0x2a0 kernel/exit.c:1119 get_signal+0x20ff/0x2210 kernel/signal.c:3038 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x98/0x670 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f965d59ce59 RSP: 002b:00007f965e4b9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: 000000000000000b RBX: 00007f965d815fa0 RCX: 00007f965d59ce59 RDX: 0400000000000041 RSI: 0000200000000000 RDI: 0000000000000007 RBP: 00007f965d632d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f965d816038 R14: 00007f965d815fa0 R15: 00007ffea4889b88 rcu: rcu_preempt kthread starved for 10599 jiffies! g34569 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:27752 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 8157 Comm: syz.3.350 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:finish_task_switch.isra.0+0x2d3/0x1010 kernel/sched/core.c:5245 Code: 2f 0a 00 00 41 c7 87 e0 0d 00 00 00 00 00 00 e9 0f 04 00 00 49 8d 7f 48 e8 ea 2a b7 09 e8 c5 9e 3b 00 fb 48 8d bb c8 16 00 00 <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84 RSP: 0018:ffffc9000372f8d8 EFLAGS: 00000206 RAX: 0000000004aeb4a3 RBX: ffff888074d9a540 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8df0fe0d RDI: ffff888074d9bc08 RBP: ffffc9000372f930 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffffffff81d55522 R12: ffff88801cb4a540 R13: 0000000000000001 R14: ffffffff90d74ce4 R15: ffff8880b853b480 FS: 00007f2abd3d56c0(0000) GS:ffff888124487000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000058 CR3: 000000005b9a8000 CR4: 00000000003526f0 Call Trace: context_switch kernel/sched/core.c:5391 [inline] __schedule+0x129d/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 futex_do_wait+0x88/0x180 kernel/futex/waitwake.c:358 __futex_wait+0x1c4/0x300 kernel/futex/waitwake.c:691 futex_wait+0xe6/0x370 kernel/futex/waitwake.c:719 do_futex+0x1ef/0x350 kernel/futex/syscalls.c:130 __do_sys_futex kernel/futex/syscalls.c:207 [inline] __se_sys_futex kernel/futex/syscalls.c:188 [inline] __x64_sys_futex+0x34f/0x4d0 kernel/futex/syscalls.c:188 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2abc59ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2abd3d50e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f2abc815fa8 RCX: 00007f2abc59ce59 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2abc815fa8 RBP: 00007f2abc815fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2abc816038 R14: 00007ffd47d0e620 R15: 00007ffd47d0e708