rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P2/1:b..l rcu: (detected by 1, t=10503 jiffies, g=34825, q=387 ncpus=2) task:kthreadd state:R running task stack:26184 pid:2 tgid:2 ppid:0 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6781 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7104 irqentry_exit+0x36/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_read_lock_held_common kernel/rcu/update.c:105 [inline] RIP: 0010:rcu_read_lock_held+0x9/0x50 kernel/rcu/update.c:349 Code: ff 4c 89 ef e8 68 18 82 00 eb 95 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa e8 17 95 db 09 01 00 00 00 85 c0 75 07 89 d0 c3 cc cc cc cc e8 a2 ec 00 00 84 RSP: 0018:ffffc90000077710 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 0000000000048ca8 RCX: ffffffff822db961 RDX: 1ffff11027fff4a6 RSI: ffffffff822db9e5 RDI: ffff88813fffa530 RBP: ffff88813fffa520 R08: 0000000000000006 R09: 0000000000001000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88801c580000 R13: ffff88823ffef400 R14: 0000000000000000 R15: 000000000224045e lookup_page_ext+0x10d/0x1d0 mm/page_ext.c:254 page_ext_iter_begin include/linux/page_ext.h:132 [inline] __update_page_owner_free_handle.constprop.0+0xaa/0x4a0 mm/page_owner.c:272 __reset_page_owner+0x93/0x1a0 mm/page_owner.c:309 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1254 [inline] __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2717 discard_slab mm/slub.c:2716 [inline] __put_partials+0x16d/0x1c0 mm/slub.c:3185 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4147 [inline] slab_alloc_node mm/slub.c:4196 [inline] __do_kmalloc_node mm/slub.c:4326 [inline] __kmalloc_noprof+0x1d4/0x510 mm/slub.c:4339 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] lsm_blob_alloc+0x68/0x90 security/security.c:684 lsm_task_alloc security/security.c:771 [inline] security_task_alloc+0x2d/0x260 security/security.c:3160 copy_process+0x250f/0x9170 kernel/fork.c:2411 kernel_clone+0xfc/0x960 kernel/fork.c:2859 kernel_thread+0xd4/0x120 kernel/fork.c:2921 create_kthread kernel/kthread.c:487 [inline] kthreadd+0x503/0x800 kernel/kthread.c:847 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: rcu_preempt kthread starved for 10258 jiffies! g34825 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:25736 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6874 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 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: 0 Comm: swapper/0 Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 93 55 02 e9 53 fb 02 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d f3 50 0e 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff8e007e08 EFLAGS: 000002c6 RAX: 0000000002451df9 RBX: 0000000000000000 RCX: ffffffff8b7bb449 RDX: 0000000000000000 RSI: ffffffff8dc0590b RDI: ffffffff8bf52ec0 RBP: fffffbfff1c12ee8 R08: 0000000000000001 R09: ffffed101708663d R10: ffff8880b84331eb R11: 0000000000000001 R12: 0000000000000000 R13: ffffffff8e097740 R14: ffffffff90878750 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124970000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555570eee5c8 CR3: 000000007b498000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:743 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 rest_init+0x16b/0x2b0 init/main.c:743 start_kernel+0x3e9/0x4d0 init/main.c:1099 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x148 net_ratelimit: 6086 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ea:26:91:7e:a9:eb, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ea:26:91:7e:a9:eb, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ea:26:91:7e:a9:eb, vlan:0) net_ratelimit: 7716 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ea:26:91:7e:a9:eb, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ea:26:91:7e:a9:eb, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)