rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5967/1:b..l P5969/3:b..l rcu: (detected by 0, t=10502 jiffies, g=12945, q=790 ncpus=2) task:syz.0.153 state:R running task stack:24672 pid:5969 tgid:5969 ppid:5229 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6708 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6732 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] filemap_map_pages+0x1707/0x1e70 mm/filemap.c:3655 do_fault_around mm/memory.c:5036 [inline] do_read_fault mm/memory.c:5069 [inline] do_fault mm/memory.c:5208 [inline] do_pte_missing mm/memory.c:3964 [inline] handle_pte_fault+0x30a0/0x6fc0 mm/memory.c:5538 __handle_mm_fault mm/memory.c:5681 [inline] handle_mm_fault+0x1109/0x1bc0 mm/memory.c:5849 do_user_addr_fault arch/x86/mm/fault.c:1338 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x459/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f980265ccc6 RSP: 002b:00007ffeccda0120 EFLAGS: 00010212 RAX: 000000110c414000 RBX: 00007f9803465720 RCX: 0000000000000003 RDX: ffffffff84ec085a RSI: 0000000000003021 RDI: 0000000000000008 RBP: 0000000000000000 R08: 00007f9802920000 R09: 00007f9802922000 R10: 0000000084ec085e R11: 0000000000000000 R12: ffffffff84ec0854 R13: 00007f9802936018 R14: 0000000000000008 R15: 0000000000000500 task:dhcpcd-run-hook state:R running task stack:25520 pid:5967 tgid:5967 ppid:5943 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:215 Code: 8b 3d 6c 76 96 0c 48 89 de 5b e9 b3 9a 5b 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 00 d7 03 00 65 8b 15 40 4a 70 7e 81 e2 00 01 ff 00 RSP: 0018:ffffc900093e7140 EFLAGS: 00000286 RAX: ffffffff814145d2 RBX: 0000000080000000 RCX: 0000000000000001 RDX: ffff8880282ada00 RSI: 0000000080000000 RDI: 0000000000000000 RBP: ffffc900093e7220 R08: ffffffff814145c5 R09: ffffffff814140bf R10: 0000000000000003 R11: ffff8880282ada00 R12: ffffc900093e79d8 R13: dffffc0000000000 R14: ffffc900093e0000 R15: ffffc900093e79e0 unwind_next_frame+0x1e82/0x2a00 arch/x86/kernel/unwind_orc.c:672 arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x76/0x430 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1101 [inline] free_unref_folios+0x103a/0x1b00 mm/page_alloc.c:2667 folios_put_refs+0x76e/0x860 mm/swap.c:1039 free_pages_and_swap_cache+0x2ea/0x690 mm/swap_state.c:332 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline] tlb_batch_pages_flush mm/mmu_gather.c:149 [inline] tlb_flush_mmu_free mm/mmu_gather.c:366 [inline] tlb_flush_mmu+0x3a3/0x680 mm/mmu_gather.c:373 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:465 exit_mmap+0x44f/0xc80 mm/mmap.c:3425 __mmput+0x115/0x390 kernel/fork.c:1345 exit_mm+0x220/0x310 kernel/exit.c:571 do_exit+0x9b2/0x27f0 kernel/exit.c:869 do_group_exit+0x207/0x2c0 kernel/exit.c:1031 __do_sys_exit_group kernel/exit.c:1042 [inline] __se_sys_exit_group kernel/exit.c:1040 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1040 x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f28c6510a90 RSP: 002b:00007ffdfac1ccc8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00005606418f5e04 RCX: 00007f28c6510a90 RDX: 00000000000000e7 RSI: 000000000000003c RDI: 0000000000000000 RBP: 0000000000000003 R08: 00007ffdfac1cdc0 R09: 0000000000000002 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffdfac1cfe8 R13: 00007ffdfac1d000 R14: 000056061929c169 R15: 00007f28c670ea80 rcu: rcu_preempt kthread starved for 10557 jiffies! g12945 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:26448 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111