rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5616/1:b..l rcu: (detected by 0, t=10503 jiffies, g=29901, q=813903 ncpus=2) task:syz-executor state:R running task stack:21160 pid:5616 tgid:5616 ppid:5606 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d4/0x5630 kernel/sched/core.c:7239 preempt_schedule_irq+0x4b/0x90 kernel/sched/core.c:7561 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x910 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:56 [inline] RIP: 0010:unwind_next_frame+0x1a27/0x2550 arch/x86/kernel/unwind_orc.c:694 Code: 00 74 09 49 8d 7e 38 e8 c7 c4 be 00 4d 8b 7e 38 49 8d 7e 08 48 89 f8 48 c1 e8 03 80 3c 18 00 74 05 e8 ad c4 be 00 4d 8b 66 08 <49> 8d 5e 10 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 RSP: 0018:ffffc90003b6f340 EFLAGS: 00000246 RAX: 1ffff9200076de7e RBX: dffffc0000000000 RCX: 0000000000000001 RDX: ffffc90003b6f428 RSI: dffffc0000000000 RDI: ffffc90003b6f3f0 RBP: 1ffffffff21ff301 R08: ffffc90003b6fbf0 R09: 0000000000000000 R10: ffffc90003b6f438 R11: fffff5200076de89 R12: ffffc90003b68000 R13: ffffffff8177710f R14: ffffc90003b6f3e8 R15: ffffc90003b6fc00 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0xc22/0xd20 mm/page_alloc.c:2950 __slab_free+0x274/0x2c0 mm/slub.c:5741 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:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] __do_kmalloc_node mm/slub.c:5333 [inline] __kmalloc_noprof+0x315/0x720 mm/slub.c:5359 _kmalloc_noprof include/linux/slab.h:992 [inline] tomoyo_realpath_from_path+0xef/0x640 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x283/0x560 security/tomoyo/file.c:827 security_inode_getattr+0x12b/0x310 security/security.c:1895 vfs_getattr+0x23/0x70 fs/stat.c:259 vfs_statx_path+0x2b/0x230 fs/stat.c:299 vfs_statx+0x12e/0x200 fs/stat.c:356 vfs_fstatat+0x11b/0x170 fs/stat.c:373 __do_sys_newfstatat fs/stat.c:538 [inline] __se_sys_newfstatat fs/stat.c:532 [inline] __x64_sys_newfstatat+0x151/0x200 fs/stat.c:532 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f20a659c71a RSP: 002b:00007ffd7b425a88 EFLAGS: 00000286 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f20a659c71a RDX: 00007ffd7b425ab0 RSI: 00007ffd7b425b40 RDI: 00000000ffffff9c RBP: 00007ffd7b425b40 R08: 00007ffd7b426b40 R09: 00000000ffffffff R10: 0000000000000100 R11: 0000000000000286 R12: 00007ffd7b426bd0 R13: 00007f20a6634474 R14: 00000000000371d4 R15: 00007ffd7b426c10 rcu: rcu_preempt kthread starved for 1204 jiffies! g29901 f0x2 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:27496 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d4/0x5630 kernel/sched/core.c:7239 __schedule_loop kernel/sched/core.c:7316 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7331 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325 kthread+0x38b/0x480 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 3273 Comm: kworker/u8:8 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:debug_lockdep_rcu_enabled+0x29/0x40 kernel/rcu/update.c:321 Code: 90 f3 0f 1e fa 31 c0 83 3d 23 19 80 04 00 74 1d 83 3d fa 48 80 04 00 74 14 65 48 8b 0d b8 45 97 07 31 c0 83 b9 a4 0b 00 00 00 <0f> 94 c0 e9 bf ff 02 00 cc cc cc cc cc cc cc cc cc cc cc cc cc cc RSP: 0018:ffffc90000a07db8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff8a0713d0 RCX: ffff888032955dc0 RDX: 00000000a42637f2 RSI: ffffffff8e4dc38e RDI: ffffffff8c4cd780 RBP: 1ffff92000140fd4 R08: ffffffff8177710f R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb5a1e0 R12: dffffc0000000000 R13: ffffffff8177710f R14: ffffc90000a07e68 R15: 1ffff92000140fcd FS: 0000000000000000(0000) GS:ffff888125024000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2a21bf14b8 CR3: 0000000065bea000 CR4: 00000000003526f0 Call Trace: rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1183 [inline] unwind_next_frame+0xb5/0x2550 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] kmem_cache_alloc_node_noprof+0x359/0x620 mm/slub.c:4989 __alloc_skb+0x1db/0x7a0 net/core/skbuff.c:704 alloc_skb include/linux/skbuff.h:1384 [inline] synproxy_send_client_synack+0x175/0xde0 net/netfilter/nf_synproxy_core.c:463 nft_synproxy_eval_v4+0x362/0x4e0 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x335/0x550 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] nft_do_chain+0x48d/0x1b10 net/netfilter/nf_tables_core.c:285 nft_do_chain_inet+0x360/0x4b0 net/netfilter/nft_chain_filter.c:162 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619 nf_hook include/linux/netfilter.h:280 [inline] NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:323 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:325 __netif_receive_skb_one_core net/core/dev.c:6264 [inline] __netif_receive_skb net/core/dev.c:6377 [inline] process_backlog+0xa6b/0x18b0 net/core/dev.c:6728 __napi_poll+0xaa/0x330 net/core/dev.c:7787 napi_poll net/core/dev.c:7850 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:8007 handle_softirqs+0x226/0x860 kernel/softirq.c:645 __do_softirq kernel/softirq.c:679 [inline] invoke_softirq kernel/softirq.c:519 [inline] __irq_exit_rcu+0xcb/0x220 kernel/softirq.c:767 irq_exit_rcu+0x9/0x30 kernel/softirq.c:784 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:debug_lockdep_rcu_enabled+0x29/0x40 kernel/rcu/update.c:321 Code: 90 f3 0f 1e fa 31 c0 83 3d 23 19 80 04 00 74 1d 83 3d fa 48 80 04 00 74 14 65 48 8b 0d b8 45 97 07 31 c0 83 b9 a4 0b 00 00 00 <0f> 94 c0 e9 bf ff 02 00 cc cc cc cc cc cc cc cc cc cc cc cc cc cc RSP: 0018:ffffc9000cc57258 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff8236172e RCX: ffff888032955dc0 RDX: 0000000045c64bcc RSI: ffffffff8e4dc38e RDI: ffffffff8c4cd780 RBP: 1ffff9200198ae68 R08: ffffffff8177710f R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb5a1e0 R12: dffffc0000000000 R13: ffffffff8177710f R14: ffffc9000cc57308 R15: 1ffff9200198ae61 rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1183 [inline] unwind_next_frame+0xb5/0x2550 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] slab_free mm/slub.c:6377 [inline] kfree+0x1c5/0x640 mm/slub.c:6692 ieee80211_ibss_rx_queued_mgmt+0x1ea1/0x2c40 net/mac80211/ibss.c:-1 ieee80211_iface_process_skb net/mac80211/iface.c:1769 [inline] ieee80211_iface_work+0x78a/0x1010 net/mac80211/iface.c:1823 cfg80211_wiphy_work+0x29e/0x420 net/wireless/core.c:541 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa88/0x14c0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x38b/0x480 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