rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6751/1:b..l (detected by 1, t=10502 jiffies, g=26285, q=147 ncpus=2) task:udevadm state:R running task stack:23952 pid:6751 ppid:4355 flags:0x00004002 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:lock_acquire+0x5f/0x4a0 kernel/locking/lockdep.c:5630 Code: 04 25 28 00 00 00 48 89 84 24 c0 00 00 00 49 bf 00 00 00 00 00 fc ff df 48 c7 44 24 60 b3 8a b5 41 48 c7 44 24 68 f7 7d 3c 8c <48> c7 44 24 70 90 3e 64 81 4c 8d 6c 24 60 49 c1 ed 03 48 b8 f1 f1 RSP: 0018:ffffc9000c577740 EFLAGS: 00000282 RAX: 5a1e7e6c98ad4200 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8cb2d620 RBP: ffffc9000c577858 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffff520018aef2d R12: ffff88807d045940 R13: ffffc9000c577d20 R14: 00007f800fb153a7 R15: dffffc0000000000 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+0xa6/0xf0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700 do_delayed_call include/linux/delayed_call.h:28 [inline] vfs_readlink+0x227/0x3e0 fs/namei.c:5136 do_readlinkat+0x251/0x490 fs/stat.c:480 __do_sys_readlink fs/stat.c:501 [inline] __se_sys_readlink fs/stat.c:498 [inline] __x64_sys_readlink+0x7b/0x90 fs/stat.c:498 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: 0033:0x7f800fb153a7 RSP: 002b:00007fffed30c8a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000059 RAX: ffffffffffffffda RBX: 00007fffed30cd80 RCX: 00007f800fb153a7 RDX: 0000000000000400 RSI: 00007fffed30c8b0 RDI: 00007fffed30cd80 RBP: 00007fffed30c8b0 R08: 00005573d507d27b R09: 0000000000000000 R10: 00005573d5074da1 R11: 0000000000000246 R12: 0000000000000400 R13: 00005573b58396b2 R14: 00005573d507d27b R15: 00007fffed30d9c0 rcu: rcu_preempt kthread starved for 9834 jiffies! g26285 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:27608 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: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742 Code: 48 89 df e8 27 c3 9c f7 e9 44 ff ff ff e8 3d 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 77 0c 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:ffffc90000177de8 EFLAGS: 000002c6 RAX: 85e68f83dd3f3c00 RBX: ffffffff8a36a2b7 RCX: 85e68f83dd3f3c00 RDX: 0000000000000001 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0de0 RBP: ffffc90000177f20 R08: ffff8880b8f3580b R09: 1ffff110171e6b01 R10: dffffc0000000000 R11: ffffed10171e6b02 R12: 1ffff9200002efc8 R13: dffffc0000000000 R14: ffff88813fef9dc0 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb0d1d846c8 CR3: 00000000237ca000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 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 start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xcf/0xdb