rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=137c/1/0x4000000000000000 softirq=19044/19046 fqs=200 rcu: (detected by 0, t=10503 jiffies, g=13473, q=980 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6102 Comm: dhcpcd-run-hook Not tainted 6.16.0-syzkaller-10355-gf2d282e1dfb3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:lookup_object lib/debugobjects.c:421 [inline] RIP: 0010:debug_object_deactivate+0x9e/0x250 lib/debugobjects.c:875 Code: c8 48 c1 e9 2f 83 e1 f8 4c 8d 3c c9 49 81 c7 c0 16 c4 99 48 8d 1c c9 48 81 c3 c8 16 c4 99 48 89 df e8 26 c2 a7 06 48 89 04 24 <4c> 89 f8 48 c1 e8 03 80 3c 28 00 74 08 4c 89 ff e8 0d f1 54 fd 4d RSP: 0018:ffffc90000a08ca8 EFLAGS: 00000046 RAX: 0000000000000802 RBX: ffffffff99c57898 RCX: dffffc0000000000 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000a08b80 RBP: dffffc0000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000141170 R12: ffff88805aae8340 R13: dffffc0000000000 R14: 0000001b1232efe3 R15: ffffffff99c57890 FS: 0000000000000000(0000) GS:ffff888125d5c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c3f77f0950 CR3: 00000000747b0000 CR4: 00000000003526f0 Call Trace: debug_hrtimer_deactivate kernel/time/hrtimer.c:450 [inline] debug_deactivate+0x1d/0x200 kernel/time/hrtimer.c:490 __run_hrtimer kernel/time/hrtimer.c:1729 [inline] __hrtimer_run_queues+0x2b0/0xc60 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 6b ed fe 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc900038aeab8 EFLAGS: 00000206 RAX: b92ba0c00efebb00 RBX: 0000000000000000 RCX: b92ba0c00efebb00 RDX: 0000000000000000 RSI: ffffffff8db72276 RDI: ffffffff8be2fe00 RBP: ffffffff8172bd05 R08: 0000000000000000 R09: ffffffff8172bd05 R10: ffffc900038aec78 R11: ffffffff81ac1ea0 R12: 0000000000000002 R13: ffffffff8e139e60 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf5/0x1f0 mm/page_owner.c:156 __set_page_owner+0x8d/0x4a0 mm/page_owner.c:329 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_frozen_pages_noprof mm/mempolicy.c:2487 [inline] alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2507 get_free_pages_noprof+0xf/0x80 mm/page_alloc.c:5207 tlb_remove_table+0x129/0x5b0 mm/mmu_gather.c:367 __pte_free_tlb arch/x86/include/asm/pgalloc.h:59 [inline] free_pte_range mm/memory.c:193 [inline] free_pmd_range mm/memory.c:211 [inline] free_pud_range mm/memory.c:245 [inline] free_p4d_range mm/memory.c:279 [inline] free_pgd_range+0x90f/0x14c0 mm/memory.c:368 free_pgtables+0x820/0x9c0 mm/memory.c:418 exit_mmap+0x444/0xb50 mm/mmap.c:1291 __mmput+0x118/0x430 kernel/fork.c:1125 exec_mmap+0x6ac/0x7d0 fs/exec.c:901 begin_new_exec+0x129c/0x2120 fs/exec.c:1156 load_elf_binary+0x998/0x2740 fs/binfmt_elf.c:995 search_binary_handler fs/exec.c:1670 [inline] exec_binprm fs/exec.c:1702 [inline] bprm_execve+0x99c/0x1450 fs/exec.c:1754 do_execveat_common+0x510/0x6a0 fs/exec.c:1860 do_execve fs/exec.c:1934 [inline] __do_sys_execve fs/exec.c:2010 [inline] __se_sys_execve fs/exec.c:2005 [inline] __x64_sys_execve+0x94/0xb0 fs/exec.c:2005 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc295068107 Code: Unable to access opcode bytes at 0x7fc2950680dd. RSP: 002b:00007fff5921e248 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 000055c3f7800fe0 RCX: 00007fc295068107 RDX: 000055c3f7801000 RSI: 000055c3f7800fe0 RDI: 000055c3f7801088 RBP: 000055c3f7801088 R08: 00007fff59221ebd R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 000055c3f7801000 R13: 00007fc29522de8b R14: 000055c3f7801000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 9505 jiffies! g13473 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:26792 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 5950 Comm: syz-executor Not tainted 6.16.0-syzkaller-10355-gf2d282e1dfb3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xd33/0x12d0 kernel/smp.c:877 Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 d6 59 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 81 55 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 65 55 RSP: 0018:ffffc90003c1f340 EFLAGS: 00000293 RAX: ffffffff81b42e3b RBX: 1ffff110170e7f59 RCX: ffff88802e4b8000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90003c1f4c0 R08: ffffffff8fa1b837 R09: 1ffffffff1f43706 R10: dffffc0000000000 R11: fffffbfff1f43707 R12: ffff8880b873fac8 R13: dffffc0000000000 R14: ffff8880b863b180 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125c5c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555902725c8 CR3: 000000000df36000 CR4: 00000000003526f0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline] flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline] tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497 free_ldt_pgtables+0x17b/0x320 arch/x86/kernel/ldt.c:411 arch_exit_mmap arch/x86/include/asm/mmu_context.h:234 [inline] exit_mmap+0x17c/0xb50 mm/mmap.c:1266 __mmput+0x118/0x430 kernel/fork.c:1125 exit_mm+0x1da/0x2c0 kernel/exit.c:581 do_exit+0x648/0x2300 kernel/exit.c:952 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:224 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd36ab84dd7 Code: Unable to access opcode bytes at 0x7fd36ab84dad. RSP: 002b:00007ffec188ece0 EFLAGS: 00000293 ORIG_RAX: 000000000000003d RAX: fffffffffffffe00 RBX: 0000000000001744 RCX: 00007fd36ab84dd7 RDX: 0000000040000000 RSI: 00007ffec188ed1c RDI: 00000000ffffffff RBP: 00007ffec188ed1c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffec188eda0 R13: 00007ffec188eda8 R14: 0000000000000009 R15: 0000000000000000