rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12/1:b..l P6716/1:b..l rcu: (detected by 1, t=10502 jiffies, g=22221, q=493 ncpus=2) task:dhcpcd-run-hook state:R running task stack:26456 pid:6716 tgid:6716 ppid:6715 task_flags:0x400040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x17b4/0x5680 kernel/sched/core.c:7183 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7507 irqentry_exit_to_kernel_mode_preempt+0x14/0x70 include/linux/irq-entry-common.h:476 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline] irqentry_exit+0x14f/0x680 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_release+0x2d7/0x3c0 kernel/locking/lockdep.c:5893 Code: 6d e1 11 00 00 00 00 eb b5 e8 e5 dc 1b 0a f7 c3 00 02 00 00 74 b9 65 48 8b 05 d5 27 e1 11 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 92 84 d5 RSP: 0018:ffffc900032f6f38 EFLAGS: 00000282 RAX: eabfe88cc9bd9000 RBX: 0000000000000202 RCX: 0000000000000046 RDX: 0000000000000003 RSI: ffffffff8e5883ae RDI: ffffffff8c4a9e60 RBP: ffff888029bf8c08 R08: ffffffff81d5dd96 R09: ffffffff8ed5cba0 R10: ffffc900032f7058 R11: ffffffff81b12010 R12: 0000000000000003 R13: 0000000000000003 R14: ffffffff8ed5cba0 R15: ffff888029bf8000 rcu_lock_release include/linux/rcupdate.h:310 [inline] rcu_read_unlock include/linux/rcupdate.h:869 [inline] is_bpf_text_address+0x28d/0x2b0 kernel/bpf/core.c:749 kernel_text_address+0xa5/0xe0 kernel/extable.c:125 __kernel_text_address+0xd/0x30 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:385 arch_stack_walk+0xfb/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5415 kmalloc_noprof include/linux/slab.h:950 [inline] slab_free_hook mm/slub.c:2641 [inline] slab_free mm/slub.c:6246 [inline] kmem_cache_free+0x156/0x650 mm/slub.c:6373 anon_vma_free mm/rmap.c:137 [inline] __put_anon_vma+0x12b/0x2d0 mm/rmap.c:2915 put_anon_vma mm/internal.h:216 [inline] unlink_anon_vmas+0x58b/0x730 mm/rmap.c:536 free_pgtables+0x836/0xb70 mm/memory.c:414 exit_mmap+0x490/0x9e0 mm/mmap.c:1312 __mmput+0x118/0x430 kernel/fork.c:1178 exec_mmap+0x3b4/0x440 fs/exec.c:893 begin_new_exec+0x1349/0x2480 fs/exec.c:1148 load_elf_binary+0xa47/0x2980 fs/binfmt_elf.c:1010 search_binary_handler fs/exec.c:1664 [inline] exec_binprm fs/exec.c:1696 [inline] bprm_execve+0x956/0x1450 fs/exec.c:1748 do_execveat_common+0x50d/0x690 fs/exec.c:1846 __do_sys_execve fs/exec.c:1930 [inline] __se_sys_execve fs/exec.c:1924 [inline] __x64_sys_execve+0x97/0xc0 fs/exec.c:1924 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdcf794b107 RSP: 002b:00007ffde49b8b68 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 0000558e415c4078 RCX: 00007fdcf794b107 RDX: 0000558e415c40a0 RSI: 0000558e415c4078 RDI: 0000558e415c4130 RBP: 0000558e415c4130 R08: 00007ffde49bdeaf R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 0000558e415c40a0 R13: 00007fdcf7b10e8b R14: 0000558e415c40a0 R15: 0000000000000000 task:kworker/u8:0 state:R running task stack:21208 pid:12 tgid:12 ppid:2 task_flags:0x24208060 flags:0x00080000 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x17b4/0x5680 kernel/sched/core.c:7183 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7507 irqentry_exit_to_kernel_mode_preempt+0x14/0x70 include/linux/irq-entry-common.h:476 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline] irqentry_exit+0x14f/0x680 kernel/entry/common.c:164 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:-1 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:119 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:140 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:172 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:191 [inline] RIP: 0010:kasan_check_range+0x110/0x2c0 mm/kasan/generic.c:200 Code: 43 80 3c 27 00 0f 85 7f 01 00 00 83 fd 05 74 63 49 bc 03 00 00 00 00 fc ff df 43 80 3c 27 00 0f 85 65 01 00 00 83 fd 04 74 49 <49> bc 04 00 00 00 00 fc ff df 43 80 3c 27 00 0f 85 4b 01 00 00 83 RSP: 0018:ffffc90000116ef8 EFLAGS: 00000293 RAX: ffffffff8632e701 RBX: dffffc0000000001 RCX: ffffffff8632e7c3 RDX: 0000000000000001 RSI: 00000000000000c0 RDI: ffff888022ba1cc8 RBP: 0000000000000001 R08: ffff888022ba1d87 R09: 1ffff110045743b0 R10: dffffc0000000000 R11: ffffed1004574399 R12: dffffc0000000003 R13: ffff888028d92000 R14: ffffed10045743b1 R15: 1ffff11004574399 __asan_memset+0x22/0x50 mm/kasan/shadow.c:84 scsi_queue_rq+0x423/0x3360 drivers/scsi/scsi_lib.c:1875 blk_mq_dispatch_rq_list+0xa70/0x1910 block/blk-mq.c:2148 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline] __blk_mq_sched_dispatch_requests+0xdcc/0x1600 block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0xd7/0x190 block/blk-mq-sched.c:329 blk_mq_run_hw_queue+0x404/0x4f0 block/blk-mq.c:2386 blk_mq_dispatch_list+0xd16/0xe10 include/linux/spinlock.h:-1 blk_mq_flush_plug_list+0x48d/0x570 block/blk-mq.c:2997 __blk_flush_plug+0x3ed/0x4d0 block/blk-core.c:1230 blk_finish_plug+0x5d/0x80 block/blk-core.c:1257 wb_writeback+0xa7b/0xb00 fs/fs-writeback.c:2277 wb_check_old_data_flush fs/fs-writeback.c:2345 [inline] wb_do_writeback fs/fs-writeback.c:2398 [inline] wb_workfn+0xb12/0xf10 fs/fs-writeback.c:2426 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: rcu_preempt kthread starved for 10603 jiffies! g22221 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:27968 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x17b4/0x5680 kernel/sched/core.c:7183 __schedule_loop kernel/sched/core.c:7262 [inline] schedule+0x164/0x360 kernel/sched/core.c:7277 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6710 Comm: syz.3.20 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:37 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:139 [inline] RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline] RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:208 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 e9 c0 13 4b 0a cc 89 f6 31 d2 e9 f6 79 82 03 66 0f 1f 44 00 RSP: 0018:ffffc900031a7a70 EFLAGS: 00000046 RAX: 0000000000029983 RBX: ffff8880b8623e40 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 0000000000029983 RDI: 0000000000000838 RBP: ffffc900031a7b28 R08: ffffffff81b316c5 R09: ffffffff9a92e588 R10: 0000000000000003 R11: ffffffff8174a6c0 R12: 0000000000029983 R13: dffffc0000000000 R14: 00000000100064a9 R15: 0000000000000020 FS: 00007f0af9d926c0(0000) GS:ffff888124dec000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdcf7a05286 CR3: 0000000072554000 CR4: 00000000003526f0 Call Trace: apic_write arch/x86/include/asm/apic.h:405 [inline] lapic_next_event+0x11/0x20 arch/x86/kernel/apic/apic.c:417 clockevents_program_event+0x385/0x5f0 kernel/time/clockevents.c:369 hrtimer_rearm kernel/time/hrtimer.c:2039 [inline] __hrtimer_rearm_deferred+0x270/0x450 kernel/time/hrtimer.c:2059 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline] irqentry_exit+0x14f/0x680 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:188 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:206 Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 da 78 e1 f5 48 89 df e8 e2 ed e1 f5 e8 bd 79 0d f6 fb bf 01 00 00 00 c2 7f d3 f5 65 8b 05 6b a3 c2 07 85 c0 74 07 5b e9 d1 47 00 00 RSP: 0018:ffffc900031a7c80 EFLAGS: 00000206 RAX: 00000000048654ed RBX: ffff88802ee4dc80 RCX: 0000000080000001 RDX: 0000000000000000 RSI: ffffffff8e31177c RDI: 0000000000000001 RBP: 0000000000000011 R08: ffffffff907443f7 R09: 1ffffffff20e887e R10: dffffc0000000000 R11: fffffbfff20e887f R12: 1ffff11005dc9be3 R13: 0000000000000000 R14: 0000000004000000 R15: ffff88802ee4df18 spin_unlock_irq include/linux/spinlock.h:402 [inline] get_signal+0x11a6/0x1330 kernel/signal.c:3040 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 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:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0af8f9aef9 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:00007f0af9d92028 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00007f0af9205fa0 RCX: 00007f0af8f9aef9 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 000000000000003e RBP: 00007f0af902fee0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0af9206038 R14: 00007f0af9205fa0 R15: 00007ffcab09f808