rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5218/1:b..l rcu: (detected by 1, t=10503 jiffies, g=15745, q=760 ncpus=2) task:udevd state:R running task stack:23648 pid:5218 tgid:5218 ppid:1 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6690 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7012 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:stack_trace_consume_entry+0xcf/0x280 kernel/stacktrace.c:93 Code: 10 00 74 26 4c 89 0c 24 48 89 df 49 89 f5 4d 89 c6 e8 e5 0c 7e 00 4d 89 f0 4c 8b 0c 24 4c 89 ee 48 ba 00 00 00 00 00 fc ff df <48> 8b 1b 45 8d 70 01 41 0f b6 04 17 84 c0 0f 85 31 01 00 00 45 89 RSP: 0018:ffffc90003ae7290 EFLAGS: 00000246 RAX: 1ffff9200075ce78 RBX: ffffc90003ae73c0 RCX: ffffffff917bd000 RDX: dffffc0000000000 RSI: ffffffff81fe6bb3 RDI: ffffc90003ae73cc RBP: ffffc90003ae73c8 R08: 0000000000000006 R09: ffffc90003ae73d0 R10: ffffc90003ae7330 R11: ffffffff818092c0 R12: 1ffff9200075ce79 R13: 1ffff9200075ce79 R14: 0000000000000000 R15: 1ffff9200075ce7a arch_stack_walk+0x10e/0x150 arch/x86/kernel/stacktrace.c:27 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x76/0x430 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638 discard_slab mm/slub.c:2677 [inline] __put_partials+0xeb/0x130 mm/slub.c:3145 put_cpu_partial+0x17c/0x250 mm/slub.c:3220 __slab_free+0x2ea/0x3d0 mm/slub.c:4449 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4085 [inline] slab_alloc_node mm/slub.c:4134 [inline] __do_kmalloc_node mm/slub.c:4263 [inline] __kmalloc_noprof+0x1a6/0x400 mm/slub.c:4276 kmalloc_noprof include/linux/slab.h:882 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822 security_inode_getattr+0x130/0x330 security/security.c:2373 vfs_getattr+0x45/0x430 fs/stat.c:204 vfs_statx_path fs/stat.c:251 [inline] vfs_statx+0x199/0x490 fs/stat.c:315 vfs_fstatat+0x145/0x190 fs/stat.c:341 __do_sys_newfstatat fs/stat.c:505 [inline] __se_sys_newfstatat fs/stat.c:499 [inline] __x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:499 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff6bf3165f4 RSP: 002b:00007fff4e3e85a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 00005579274cd6d8 RCX: 00007ff6bf3165f4 RDX: 00007fff4e3e85b8 RSI: 00005579274bd897 RDI: 00000000ffffff9c RBP: 00005579342a0448 R08: 0006266e77e83452 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 0006266e77e83452 R15: 00005579274c1dca rcu: rcu_preempt kthread starved for 10544 jiffies! g15745 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:24272 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6782 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 24 Comm: ksoftirqd/1 Not tainted 6.12.0-rc6-syzkaller-00166-g55d42a0c3f9c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:lock_release+0x658/0xa30 kernel/locking/lockdep.c:5850 Code: 3c 3b 00 74 08 4c 89 f7 e8 85 2b 8e 00 f6 84 24 91 00 00 00 02 75 77 41 f7 c5 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 4b c7 44 27 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc900001e6a00 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff9200003cd52 RCX: ffffc900001e6a03 RDX: 0000000000000002 RSI: ffffffff8c0adc40 RDI: ffffffff8c610960 RBP: ffffc900001e6b38 R08: ffffffff901d096f R09: 1ffffffff203a12d R10: dffffc0000000000 R11: fffffbfff203a12e R12: 1ffff9200003cd4c R13: 0000000000000246 R14: ffffc900001e6a90 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005579342aed88 CR3: 000000007796a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_release include/linux/rcupdate.h:347 [inline] rcu_read_unlock include/linux/rcupdate.h:880 [inline] net_generic+0x1eb/0x240 include/net/netns/generic.h:48 brnf_get_logical_dev+0x30/0x280 net/bridge/br_netfilter_hooks.c:460 br_nf_forward_ip+0x5f8/0x7b0 net/bridge/br_netfilter_hooks.c:745 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x2a7/0x460 include/linux/netfilter.h:312 __br_forward+0x489/0x660 net/bridge/br_forward.c:115 br_handle_frame_finish+0x18ba/0x1fe0 net/bridge/br_input.c:215 br_nf_hook_thresh+0x472/0x590 br_nf_pre_routing_finish_ipv6+0xaa0/0xdd0 NF_HOOK include/linux/netfilter.h:314 [inline] br_nf_pre_routing_ipv6+0x379/0x770 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:277 [inline] br_handle_frame+0x9fd/0x1530 net/bridge/br_input.c:424 __netif_receive_skb_core+0x13e8/0x4570 net/core/dev.c:5564 __netif_receive_skb_one_core net/core/dev.c:5668 [inline] __netif_receive_skb+0x12f/0x650 net/core/dev.c:5783 process_backlog+0x662/0x15b0 net/core/dev.c:6115 __napi_poll+0xcb/0x490 net/core/dev.c:6779 napi_poll net/core/dev.c:6848 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6970 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:927 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244