rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4475/1:b..l (detected by 0, t=10502 jiffies, g=20045, q=102 ncpus=2) task:udevd state:R running task stack:23040 pid:4475 ppid:3638 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873 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:kasan_mem_to_shadow include/linux/kasan.h:59 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [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+0x54/0x290 mm/kasan/generic.c:189 Code: 0f 82 43 02 00 00 49 bf 01 00 00 00 00 fc ff df 49 89 fb 49 c1 eb 03 49 b8 00 00 00 00 00 fc ff df 4f 8d 0c 03 48 8d 5c 37 ff <48> c1 eb 03 4e 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 4d 85 RSP: 0018:ffffc9000506f700 EFLAGS: 00000a02 RAX: ffffffff89fe4c01 RBX: ffffffff96e3c7c3 RCX: ffffffff89fe4c36 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff96e3c7c0 RBP: ffffc9000506f8f0 R08: dffffc0000000000 R09: fffffbfff2dc78f8 R10: 0000000000000003 R11: 1ffffffff2dc78f8 R12: ffff88807f121da8 R13: ffff88807b6c5c80 R14: 0000000000000001 R15: dffffc0000000001 instrument_atomic_read_write include/linux/instrumented.h:102 [inline] atomic_inc include/linux/atomic/atomic-instrumented.h:190 [inline] mt_validate_nulls lib/maple_tree.c:7198 [inline] mt_validate+0x4426/0x4c90 lib/maple_tree.c:7249 validate_mm_mt+0xcd/0x420 mm/mmap.c:295 validate_mm+0xcc/0x2b0 mm/mmap.c:332 remove_mt mm/mmap.c:2322 [inline] do_mas_align_munmap+0xf98/0x1220 mm/mmap.c:2595 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650 __vm_munmap+0x18d/0x290 mm/mmap.c:2936 __do_sys_munmap mm/mmap.c:2961 [inline] __se_sys_munmap mm/mmap.c:2958 [inline] __x64_sys_munmap+0x5c/0x70 mm/mmap.c:2958 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f727611e097 RSP: 002b:00007ffce4cfe968 EFLAGS: 00000246 ORIG_RAX: 000000000000000b RAX: ffffffffffffffda RBX: 000055fc3f17b520 RCX: 00007f727611e097 RDX: 000055fc3f17bd68 RSI: 0000000000000200 RDI: 00007f727678e000 RBP: 000000000000000b R08: 000055fc3f17b4f0 R09: 0000000000000003 R10: 0000000000000000 R11: 0000000000000246 R12: 000055fc3f1680b0 R13: 00007f727686039c R14: 0000000000001600 R15: 0000000000000009 rcu: rcu_preempt kthread starved for 10538 jiffies! g20045 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:27840 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_timeout+0x15c/0x280 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x95/0x380 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5654 Comm: syz.1.231 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:lock_acquire+0x88/0x490 kernel/locking/lockdep.c:5630 Code: 8c 48 c7 44 24 70 90 01 63 81 4c 8d 6c 24 60 49 c1 ed 03 48 b8 f1 f1 f1 f1 00 f2 f2 f2 4b 89 44 3d 00 66 43 c7 44 3d 09 f3 f3 <43> c6 44 3d 0b f3 0f 1f 44 00 00 65 44 8b 35 75 17 9f 7e 48 c7 c0 RSP: 0018:ffffc900001e07a0 EFLAGS: 00000806 RAX: f2f2f200f1f1f1f1 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c92b120 RBP: ffffc900001e08b8 R08: 0000000000000000 R09: 0000000000000000 R10: fffff5200003c139 R11: 1ffff9200003c137 R12: ffff88807abbbb80 R13: 1ffff9200003c100 R14: ffffffffa00009a4 R15: dffffc0000000000 FS: 00007f91ef4bc6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff7319b7198 CR3: 0000000079a52000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] is_bpf_text_address+0x43/0x2a0 kernel/bpf/core.c:735 kernel_text_address+0x9c/0xd0 kernel/extable.c:125 __kernel_text_address+0x9/0x30 kernel/extable.c:79 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323 arch_stack_walk+0xf2/0x140 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383 __sigqueue_alloc+0x40c/0x520 kernel/signal.c:436 __send_signal_locked+0x22f/0xde0 kernel/signal.c:1129 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x1f6/0x250 kernel/signal.c:1449 do_bpf_send_signal+0x7b/0x150 kernel/trace/bpf_trace.c:840 irq_work_single+0xd1/0x230 kernel/irq_work.c:211 irq_work_run_list kernel/irq_work.c:242 [inline] irq_work_run+0x152/0x2e0 kernel/irq_work.c:251 __sysvec_irq_work+0xba/0x350 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x98/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline] RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206 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 c3 89 f6 31 d2 e9 7f e8 f7 02 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc9000d107cb0 EFLAGS: 00000246 RAX: 00000000000000f6 RBX: ffffffff8c3d8b88 RCX: 000000000000083f RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff52001a20f85 R10: fffff52001a20f85 R11: 1ffff92001a20f84 R12: ffff8880b8f33e01 R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000020 arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31 irq_work_queue+0x95/0x140 kernel/irq_work.c:114 bpf_send_signal_common+0x2b2/0x420 kernel/trace/bpf_trace.c:879 ____bpf_send_signal kernel/trace/bpf_trace.c:888 [inline] bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:886 bpf_prog_7ba5217f62dcd359+0x38/0x3c bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline] bpf_trace_run2+0x1cd/0x3b0 kernel/trace/bpf_trace.c:2324 __bpf_trace_sys_enter+0x60/0x70 include/trace/events/syscalls.h:18 trace_sys_enter+0x6b/0x80 include/trace/events/syscalls.h:18 syscall_trace_enter+0xf0/0x150 kernel/entry/common.c:81 do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:77 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f91ee52b829 Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25 RSP: 002b:00007f91ef4bbb40 EFLAGS: 00000246 ORIG_RAX: 000000000000000f RAX: ffffffffffffffda RBX: 00007f91ee7e6098 RCX: 00007f91ee52b829 RDX: 00007f91ef4bbb40 RSI: 00007f91ef4bbc70 RDI: 0000000000000011 RBP: 00007f91ee7e6090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f91ee7e6128 R14: 00007fff311a1d90 R15: 00007fff311a1e78