rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=59cc/1/0x4000000000000002 softirq=30571/30572 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7879/1:b..l P59/1:b..l rcu: (detected by 1, t=10505 jiffies, g=26513, q=178 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.16.0-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:__asan_memset+0x0/0x50 mm/kasan/shadow.c:83 Code: 48 8b 0c 24 ba 01 00 00 00 e9 bc e4 ff ff 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 41 56 53 48 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 RSP: 0018:ffffc90000007ce8 EFLAGS: 00000046 RAX: ffffffff8b6297f7 RBX: 1ffff110170c4f82 RCX: ffffffff8de95280 RDX: 0000000000000018 RSI: 0000000000000000 RDI: ffff88802730b340 RBP: 0000000000000000 R08: ffffffff8fa0b3f7 R09: 1ffffffff1f4167e R10: dffffc0000000000 R11: fffffbfff1f4167f R12: ffff88802730b340 R13: dffffc0000000000 R14: ffff8880b8627c10 R15: ffff88802730b340 FS: 0000000000000000(0000) GS:ffff888125c57000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0b2c983ad8 CR3: 000000007a648000 CR4: 00000000003526f0 Call Trace: rb_link_node include/linux/rbtree.h:63 [inline] rb_add_cached include/linux/rbtree.h:182 [inline] timerqueue_add+0x186/0x200 lib/timerqueue.c:40 __run_hrtimer kernel/time/hrtimer.c:1778 [inline] __hrtimer_run_queues+0x656/0xc60 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:sched_core_balance+0x156/0xf00 kernel/sched/core.c:6428 Code: 6f 8a 8b e8 cc 46 0b 00 4c 89 74 24 68 4c 89 7c 24 48 e9 3b 0d 00 00 4c 89 f7 e8 35 f7 d5 09 e8 10 94 34 00 fb 48 8b 5c 24 70 <83> fb 08 0f 83 06 0d 00 00 4c 8d 34 dd 70 8c ba 8d 4c 89 f0 48 c1 RSP: 0018:ffffffff8de07980 EFLAGS: 00000282 RAX: 769b670b72590800 RBX: 0000000000000000 RCX: 769b670b72590800 RDX: 0000000000000000 RSI: ffffffff8d982fba RDI: ffffffff8be1ba40 RBP: ffffffff8de07ae8 R08: ffffffff8fa0b3f7 R09: 1ffffffff1f4167e R10: dffffc0000000000 R11: fffffbfff1f4167f R12: ffff8880b8639e00 R13: dffffc0000000000 R14: ffff8880b8639e00 R15: 0000000000000000 do_balance_callbacks kernel/sched/core.c:5043 [inline] __balance_callbacks kernel/sched/core.c:5097 [inline] finish_lock_switch kernel/sched/core.c:5144 [inline] finish_task_switch+0x3a7/0x950 kernel/sched/core.c:5263 context_switch kernel/sched/core.c:5400 [inline] __schedule+0x16b2/0x4c90 kernel/sched/core.c:6786 schedule_idle+0x52/0x90 kernel/sched/core.c:6905 do_idle+0x4ad/0x510 kernel/sched/idle.c:353 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423 rest_init+0x2de/0x300 init/main.c:745 start_kernel+0x47d/0x500 init/main.c:1102 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x147 task:kworker/u8:4 state:R running task stack:21032 pid:59 tgid:59 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x16aa/0x4c90 kernel/sched/core.c:6786 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7109 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:rcu_is_watching+0x67/0xb0 kernel/rcu/tree.c:746 Code: 89 f7 e8 2c e2 78 00 48 c7 c3 58 bf 9d 92 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 34 8b 03 65 ff 0d 39 65 f5 10 <74> 11 83 e0 04 c1 e8 02 5b 41 5e 41 5f e9 17 38 c2 09 cc e8 a1 7b RSP: 0018:ffffc9000210fa00 EFLAGS: 00000286 RAX: 00000000005259cc RBX: ffff8880b8632f58 RCX: d455e29e93603500 RDX: ffff88801c785a00 RSI: ffffffff8be1ba20 RDI: ffffffff8be1b9e0 RBP: ffff88802a189968 R08: 0000000000000000 R09: ffffffff8b345592 R10: dffffc0000000000 R11: fffffbfff1f4167f R12: dffffc0000000000 R13: ffffffff8b345592 R14: ffffffff8dba8c70 R15: dffffc0000000000 rcu_read_lock include/linux/rcupdate.h:842 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x10c/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 task:syz-executor state:R running task stack:21896 pid:7879 tgid:7879 ppid:7870 task_flags:0x400140 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x16aa/0x4c90 kernel/sched/core.c:6786 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7109 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_release+0x2b5/0x3e0 kernel/locking/lockdep.c:5896 Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 fb 42 fe 10 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000ab575f0 EFLAGS: 00000206 RAX: adf663275cef8a00 RBX: 0000000000000202 RCX: adf663275cef8a00 RDX: 0000000000000000 RSI: ffffffff8db6fcc6 RDI: ffffffff8be1ba40 RBP: ffff8880335a0af0 R08: ffffc9000ab57ee0 R09: 0000000000000000 R10: ffffc9000ab57778 R11: fffff5200156aef1 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8e13f0e0 R15: ffff8880335a0000 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf7/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc65/0xe60 mm/page_alloc.c:2706 vfree+0x25a/0x400 mm/vmalloc.c:3434 __do_replace+0x827/0x980 net/ipv6/netfilter/ip6_tables.c:1107 do_replace net/ipv6/netfilter/ip6_tables.c:1158 [inline] do_ip6t_set_ctl+0xa16/0xce0 net/ipv6/netfilter/ip6_tables.c:1644 nf_setsockopt+0x26c/0x290 net/netfilter/nf_sockopt.c:101 do_sock_setsockopt+0x179/0x1b0 net/socket.c:2296 __sys_setsockopt net/socket.c:2321 [inline] __do_sys_setsockopt net/socket.c:2327 [inline] __se_sys_setsockopt net/socket.c:2324 [inline] __x64_sys_setsockopt+0x13f/0x1b0 net/socket.c:2324 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: 0033:0x7f0b2c790a5a RSP: 002b:00007ffd723024e8 EFLAGS: 00000202 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007ffd72302570 RCX: 00007f0b2c790a5a RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00000000000002e8 R09: 0079746972756365 R10: 00007f0b2c984140 R11: 0000000000000202 R12: 00007f0b2c9840e0 R13: 00007ffd7230250c R14: 0000000000000000 R15: 00007f0b2c984e60 rcu: rcu_preempt kthread starved for 10505 jiffies! g26513 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:27192 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x16aa/0x4c90 kernel/sched/core.c:6786 __schedule_loop kernel/sched/core.c:6864 [inline] schedule+0x165/0x360 kernel/sched/core.c:6879 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/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: 1 UID: 0 PID: 8256 Comm: modprobe Not tainted 6.16.0-syzkaller #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:340 [inline] RIP: 0010:smp_call_function_many_cond+0xf69/0x12d0 kernel/smp.c:885 Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 80 6e 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 2b 6a 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 10 6a 0b RSP: 0018:ffffc9000ab676e0 EFLAGS: 00000293 RAX: ffffffff81b4bbb0 RBX: ffff8880b873b040 RCX: ffff8880275d3c00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000ab67840 R08: ffffc9000ab67787 R09: 1ffff9200156cef0 R10: dffffc0000000000 R11: fffff5200156cef1 R12: 1ffff110170c835d R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8641ae8 FS: 0000000000000000(0000) GS:ffff888125d57000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c34cb07 CR3: 0000000078400000 CR4: 00000000003526f0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 __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 exit_mmap+0x44c/0xb50 mm/mmap.c:1297 __mmput+0x118/0x410 kernel/fork.c:1121 exit_mm+0x1da/0x2c0 kernel/exit.c:581 do_exit+0x648/0x22e0 kernel/exit.c:952 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105 __do_sys_exit_group kernel/exit.c:1116 [inline] __se_sys_exit_group kernel/exit.c:1114 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1114 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232 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: 0033:0x7f246462a6c5 Code: Unable to access opcode bytes at 0x7f246462a69b. RSP: 002b:00007ffc7fbe4098 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f246472bfe8 RCX: 00007f246462a6c5 RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000001 RBP: 0000000000000001 R08: 00007ffc7fbe4028 R09: 0000000000000000 R10: 00007ffc7fbe3ec0 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f246472a680 R15: 00007f246472c000