rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5956/1:b..l rcu: (detected by 1, t=10503 jiffies, g=8165, q=1472205 ncpus=2) task:syz-executor state:R running task stack:26768 pid:5956 tgid:5956 ppid:5230 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6997 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_save+0x12c/0x1d0 kernel/stacktrace.c:123 Code: 25 c0 d7 03 00 48 c7 c7 70 68 80 81 4c 89 f6 31 c9 e8 d8 2a b7 ff 48 89 d8 48 c1 e8 03 42 0f b6 04 28 84 c0 75 79 8b 44 24 50 <48> c7 44 24 20 0e 36 e0 45 4b c7 44 3d 00 00 00 00 00 43 c7 44 3d RSP: 0018:ffffc9001699f460 EFLAGS: 00000246 RAX: 0000000000000010 RBX: ffffc9001699f4b0 RCX: ffffffff917b9000 RDX: dffffc0000000000 RSI: ffffffff8bc4b2b3 RDI: ffffc9001699f4ac RBP: ffffc9001699f530 R08: 000000000000000f R09: ffffc9001699f4b0 R10: ffffc9001699f410 R11: ffffffff81806870 R12: ffffc9001699f580 R13: dffffc0000000000 R14: ffffc9001699f4a0 R15: 1ffff92002d33e90 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:2678 [inline] __put_partials+0xeb/0x130 mm/slub.c:3146 put_cpu_partial+0x17c/0x250 mm/slub.c:3221 __slab_free+0x2ea/0x3d0 mm/slub.c:4450 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:4086 [inline] slab_alloc_node mm/slub.c:4135 [inline] __do_kmalloc_node mm/slub.c:4264 [inline] __kmalloc_noprof+0x1a6/0x400 mm/slub.c:4277 kmalloc_noprof include/linux/slab.h:882 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x26f/0x540 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x59e/0x5e0 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822 tomoyo_path_symlink+0xde/0x120 security/tomoyo/tomoyo.c:212 security_path_symlink+0x16f/0x370 security/security.c:1978 do_symlinkat+0x136/0x3a0 fs/namei.c:4639 __do_sys_symlinkat fs/namei.c:4657 [inline] __se_sys_symlinkat fs/namei.c:4654 [inline] __x64_sys_symlinkat+0x95/0xb0 fs/namei.c:4654 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: 0033:0x7fbbd1b7d577 RSP: 002b:00007ffecb23a528 EFLAGS: 00000206 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbbd1b7d577 RDX: 00007fbbd1bf19b4 RSI: 00000000ffffff9c RDI: 00007ffecb23a5b0 RBP: 00007ffecb23a55c R08: 0000000000000017 R09: 00007ffecb23a277 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000032 R13: 0000000000012895 R14: 000000000001287a R15: 00007ffecb23a5b0 rcu: rcu_preempt kthread starved for 10528 jiffies! g8165 f0x2 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:25888 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9 Comm: kworker/0:1 Not tainted 6.11.0-syzkaller-11546-ga0ffa68c70b3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:206 [inline] RIP: 0010:unwind_next_frame+0x16d/0x22d0 arch/x86/kernel/unwind_orc.c:494 Code: 89 6c 24 08 4c 89 74 24 68 48 89 2c 24 0f 84 0c 01 00 00 48 c7 c0 00 00 00 81 49 39 c7 0f 82 08 01 00 00 48 c7 c0 00 00 00 8c <49> 39 c7 0f 83 f8 00 00 00 48 c7 c0 00 00 00 81 4d 89 fe 49 29 c6 RSP: 0018:ffffc90000006810 EFLAGS: 00000206 RAX: ffffffff8c000000 RBX: ffffc90000006928 RCX: ffffffff9a3c5903 RDX: dffffc0000000000 RSI: ffffffff89f7e6e2 RDI: 0000000000000001 RBP: ffffc90000006915 R08: 0000000000000009 R09: ffffc900000069d0 R10: ffffc90000006930 R11: ffffffff81806870 R12: dffffc0000000000 R13: ffffc900000068e0 R14: ffffffff89f7e6e2 R15: ffffffff89f7e6e1 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffef98519ac CR3: 000000000e734000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4086 [inline] slab_alloc_node mm/slub.c:4135 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4142 fill_pool lib/debugobjects.c:168 [inline] debug_objects_fill_pool+0x453/0x9f0 lib/debugobjects.c:615 debug_object_activate+0x135/0x510 lib/debugobjects.c:704 debug_rcu_head_queue kernel/rcu/rcu.h:224 [inline] __call_rcu_common kernel/rcu/tree.c:3071 [inline] call_rcu+0x97/0xa70 kernel/rcu/tree.c:3190 refdst_drop include/net/dst.h:263 [inline] skb_dst_drop include/net/dst.h:275 [inline] skb_release_head_state+0x73/0x250 net/core/skbuff.c:1174 skb_release_all net/core/skbuff.c:1188 [inline] __kfree_skb net/core/skbuff.c:1204 [inline] consume_skb+0x60/0xf0 net/core/skbuff.c:1436 nft_synproxy_eval_v4+0x3d2/0x610 net/netfilter/nft_synproxy.c:60 nft_synproxy_do_eval+0x362/0xa60 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161 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+0x29e/0x450 include/linux/netfilter.h:312 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5666 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5779 process_backlog+0x662/0x15b0 net/core/dev.c:6111 __napi_poll+0xcb/0x490 net/core/dev.c:6775 napi_poll net/core/dev.c:6844 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6966 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 neigh_periodic_work+0xb35/0xd50 net/core/neighbour.c:1019 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 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