rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8009/1:b..l P46/1:b..l (detected by 0, t=10502 jiffies, g=33861, q=304606 ncpus=2) task:kworker/u4:3 state:R running task stack:22224 pid:46 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker 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:bytes_is_nonzero mm/kasan/generic.c:84 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x7d/0x290 mm/kasan/generic.c:189 Code: 8d 44 3e ff 4d 89 c1 49 c1 e9 03 4b 8d 1c 21 49 89 df 4d 29 df 49 83 ff 10 7f 29 4d 85 ff 0f 84 38 01 00 00 4c 89 cb 48 f7 d3 <4c> 01 f3 41 80 3b 00 0f 85 86 01 00 00 49 ff c3 48 ff c3 75 ee e9 RSP: 0018:ffffc90000b77a90 EFLAGS: 00000202 RAX: 0000000000000001 RBX: e00000000e3c079a RCX: ffffffff81644064 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8e1fc328 RBP: ffffc90000b77bc8 R08: ffffffff8e1fc32f R09: 1ffffffff1c3f865 R10: dffffc0000000000 R11: fffffbfff1c3f865 R12: dffffc0000000001 R13: 1ffff9200016ef64 R14: 1ffffffff1c3f865 R15: 0000000000000001 instrument_atomic_read include/linux/instrumented.h:72 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:444 [inline] cpu_online include/linux/cpumask.h:1030 [inline] trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0xd4/0x4a0 kernel/locking/lockdep.c:5633 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xeb/0x600 net/batman-adv/network-coding.c:719 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 task:sed state:R running task stack:24336 pid:8009 ppid:8008 flags:0x00004000 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_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696 RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_cmp4+0x13/0x80 kernel/kcov.c:287 Code: 11 08 02 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 90 48 8b 04 24 65 48 8b 15 64 fb 7f 7e 65 8b 0d 65 fb 7f 7e <81> e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 1c 16 00 00 RSP: 0018:ffffc900055df1b8 EFLAGS: 00000293 RAX: ffffffff8a19d5b2 RBX: 000000000000000c RCX: 0000000080000000 RDX: ffff88802e73d940 RSI: 000000000000000f RDI: 000000000000000c RBP: ffffc900055df370 R08: ffff88802e73d940 R09: 0000000000000003 R10: 0000000000000003 R11: 0000000000000000 R12: dffffc0000000000 R13: ffff88807c8fe268 R14: 0000000000000001 R15: 000000000000000f mas_validate_limits lib/maple_tree.c:7164 [inline] mt_validate+0x2322/0x4cb0 lib/maple_tree.c:7244 validate_mm_mt+0xe2/0x440 mm/mmap.c:295 validate_mm+0xe1/0x2e0 mm/mmap.c:332 __vma_adjust+0x1855/0x1cd0 mm/mmap.c:879 vma_adjust include/linux/mm.h:2810 [inline] __split_vma+0x3a7/0x500 mm/mmap.c:-1 do_mas_align_munmap+0x7b9/0x12b0 mm/mmap.c:2501 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650 __mmap_region mm/mmap.c:2698 [inline] mmap_region+0x6e0/0x1ca0 mm/mmap.c:2916 do_mmap+0x964/0xfd0 mm/mmap.c:1436 vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:520 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482 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: 0033:0x7fe3d751c242 RSP: 002b:00007ffd404ee3f8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fe3d71f6000 RCX: 00007fe3d751c242 RDX: 0000000000000001 RSI: 0000000000002000 RDI: 00007fe3d71f6000 RBP: 0000000000000812 R08: 0000000000000003 R09: 0000000000005000 R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffd404ee480 R13: 00007fe3d71fb0c0 R14: 00007ffd404ee830 R15: 00000fffa809dc82 rcu: rcu_preempt kthread starved for 9262 jiffies! g33861 f0x2 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:28016 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 10/25/2025 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742 Code: 48 89 df e8 a7 10 9d f7 e9 44 ff ff ff e8 7d 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 87 5d 50 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: c60f4d8574c0fd00 RBX: ffffffff8a3651a7 RCX: c60f4d8574c0fd00 RDX: 0000000000000001 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0c20 RBP: ffffffff8c807ec0 R08: ffff8880b8e3580b R09: 1ffff110171c6b01 R10: dffffc0000000000 R11: ffffed10171c6b02 R12: 1ffffffff1900fbc R13: dffffc0000000000 R14: ffffffff8c8bc740 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7b1f1337a7 CR3: 00000000268aa000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000008 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:191 [inline] do_idle+0x20d/0x5a0 kernel/sched/idle.c:303 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401 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