rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5875/1:b..l rcu: (detected by 0, t=10502 jiffies, g=19497, q=6132 ncpus=2) task:udevd state:R running task stack:24728 pid:5875 tgid:5875 ppid:4989 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x17b4/0x5680 kernel/sched/core.c:7188 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7512 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline] irqentry_exit+0x14f/0x730 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x8/0x90 kernel/kcov.c:321 Code: 89 44 11 20 e9 94 98 4a ff cc 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0d 68 27 73 11 65 8b 15 89 27 73 11 81 e2 00 01 ff 00 74 RSP: 0018:ffffc90004f074a0 EFLAGS: 00000246 RAX: ffffffff823aa3c1 RBX: dffffc0000000000 RCX: ffffffff823aa2e3 RDX: 0000000000000001 RSI: 0000000000004749 RDI: 0000000000000000 RBP: ffff88801d5646c4 R08: ffff88801d564687 R09: 1ffff11003aac8d0 R10: dffffc0000000000 R11: ffffed1003aac8d1 R12: 0000000000054749 R13: 00000000000016f3 R14: 0000000000000000 R15: 0000000000054749 page_ext_iter_next_fast_possible include/linux/page_ext.h:80 [inline] page_ext_iter_next include/linux/page_ext.h:156 [inline] __update_page_owner_free_handle+0x291/0x470 mm/page_owner.c:284 __reset_page_owner+0x85/0x1f0 mm/page_owner.c:321 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1402 [inline] __free_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2943 __slab_free+0x274/0x2c0 mm/slub.c:5608 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4569 [inline] slab_alloc_node mm/slub.c:4898 [inline] kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4905 vm_area_dup+0x2b/0x680 mm/vma_init.c:123 __split_vma+0x1dc/0xa40 mm/vma.c:516 vms_gather_munmap_vmas+0x32d/0x1380 mm/vma.c:1427 do_vmi_align_munmap+0x2b4/0x4b0 mm/vma.c:1595 do_vmi_munmap+0x252/0x2d0 mm/vma.c:1652 __vm_munmap+0x22c/0x3d0 mm/vma.c:3284 __do_sys_munmap mm/mmap.c:1079 [inline] __se_sys_munmap mm/mmap.c:1076 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:1076 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: 0033:0x7ff45291e097 RSP: 002b:00007ffddb67d898 EFLAGS: 00000246 ORIG_RAX: 000000000000000b RAX: ffffffffffffffda RBX: 000055e7d0a6c180 RCX: 00007ff45291e097 RDX: 000055e7d0a73f78 RSI: 0000000000000200 RDI: 00007ff452f89000 RBP: 0000000000000010 R08: 000055e7d0a6c150 R09: 0000000000000003 R10: 0000000000000000 R11: 0000000000000246 R12: 000055e7d0a680b0 R13: 00007ff4530c239c R14: 0000000000002000 R15: 0000000000000009 rcu: rcu_preempt kthread starved for 10542 jiffies! g19497 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:27544 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x17b4/0x5680 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] schedule+0x164/0x360 kernel/sched/core.c:7282 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: CPU: 0 UID: 0 PID: 6298 Comm: syz.1.90 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:104 [inline] RIP: 0010:__local_bh_enable_ip+0xd8/0x130 kernel/softirq.c:457 Code: 8b e8 7c 04 20 0a 65 66 8b 05 4c 03 b1 11 66 85 c0 75 32 bf 01 00 00 00 e8 a5 f9 0b 00 e8 10 02 46 00 fb 65 8b 05 28 03 b1 11 <85> c0 75 05 e8 1f ce ab ff 5b 41 5e e9 f2 73 88 ff cc 90 0f 0b 90 RSP: 0018:ffffc90004797908 EFLAGS: 00000206 RAX: 0000000080000000 RBX: 0000000000000200 RCX: 0000000000000046 RDX: 0000000000000000 RSI: ffffffff8dfa3a1a RDI: ffffffff8c28aa60 RBP: ffffc90004797b70 R08: ffffffff903096f7 R09: 1ffffffff20612de R10: dffffc0000000000 R11: fffffbfff20612df R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff89c07521 R15: 0000000000000000 FS: 00007f9220e216c0(0000) GS:ffff888125293000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b34a0cff8 CR3: 00000000539af000 CR4: 0000000000350ef0 Call Trace: local_bh_enable include/linux/bottom_half.h:33 [inline] bpf_test_run+0x3a8/0x830 net/bpf/test_run.c:426 bpf_prog_test_run_nf+0x460/0x790 net/bpf/test_run.c:1831 bpf_prog_test_run+0x2c7/0x340 kernel/bpf/syscall.c:4742 __sys_bpf+0x643/0x950 kernel/bpf/syscall.c:6266 __do_sys_bpf kernel/bpf/syscall.c:6361 [inline] __se_sys_bpf kernel/bpf/syscall.c:6359 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6359 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: 0033:0x7f921ff9cdd9 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:00007f9220e21028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f9220216180 RCX: 00007f921ff9cdd9 RDX: 0000000000000050 RSI: 00002000000002c0 RDI: 000000000000000a RBP: 00007f9220032d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9220216218 R14: 00007f9220216180 R15: 00007ffc3d932938