rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6072/1:b..l rcu: (detected by 1, t=10503 jiffies, g=11793, q=1250 ncpus=2) task:syz.4.59 state:R running task stack:26840 pid:6072 tgid:6067 ppid:5839 task_flags:0x40044c flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7090 irqentry_exit+0x6f/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5870 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 6b 41 d7 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000b63f3d8 EFLAGS: 00000206 RAX: 6410d69db4880900 RBX: 0000000000000000 RCX: 6410d69db4880900 RDX: 0000000000000000 RSI: ffffffff8d935758 RDI: ffffffff8bc1d220 RBP: ffffffff817199f5 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff817199f5 R12: 0000000000000002 R13: ffffffff8df3b860 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf7/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0xb0e/0xcd0 mm/page_alloc.c:2725 discard_slab mm/slub.c:2716 [inline] __put_partials+0x161/0x1c0 mm/slub.c:3185 put_cpu_partial+0x17c/0x250 mm/slub.c:3260 __slab_free+0x2f7/0x400 mm/slub.c:4512 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 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] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4203 taskstats_tgid_alloc kernel/taskstats.c:576 [inline] taskstats_exit+0x14a/0xa30 kernel/taskstats.c:615 do_exit+0x854/0x2550 kernel/exit.c:938 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 get_signal+0x125e/0x1310 kernel/signal.c:3034 arch_do_signal_or_restart+0x95/0x780 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x8b/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f742ad8e969 RSP: 002b:00007f742bbeb0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f742afb6168 RCX: 00007f742ad8e969 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f742afb6168 RBP: 00007f742afb6160 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f742afb616c R13: 0000000000000000 R14: 00007f742b0df940 R15: 00007f742b0dfa28 rcu: rcu_preempt kthread starved for 1642 jiffies! g11793 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:27304 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2046 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2248 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 4175 Comm: kworker/u8:7 Not tainted 6.15.0-rc4-syzkaller-00256-g95d3481af6dc #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:check_region_inline mm/kasan/generic.c:171 [inline] RIP: 0010:kasan_check_range+0x6/0x2b0 mm/kasan/generic.c:189 Code: 8d e8 8e 38 e5 ff 90 0f 0b cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 b0 01 <48> 85 f6 0f 84 b8 01 00 00 55 41 57 41 56 41 55 41 54 53 4c 8d 04 RSP: 0018:ffffc90000a07890 EFLAGS: 00000246 RAX: 1ffff92000140f01 RBX: 0000000000000010 RCX: ffffffff8171a5e8 RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc90000a079d8 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff817199f5 R12: ffffc90000a08ee0 R13: ffffc90000a079d8 R14: ffffc90000a079d8 R15: ffffc90000a079d0 FS: 0000000000000000(0000) GS:ffff8881261cb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000005e030 CR3: 00000000623e4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __asan_memset+0x22/0x50 mm/kasan/shadow.c:84 unwind_next_frame+0xc98/0x2390 arch/x86/kernel/unwind_orc.c:592 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2380 [inline] slab_free mm/slub.c:4642 [inline] kmem_cache_free+0x192/0x3f0 mm/slub.c:4744 skb_release_all net/core/skbuff.c:1160 [inline] __kfree_skb net/core/skbuff.c:1176 [inline] sk_skb_reason_drop+0xe9/0x170 net/core/skbuff.c:1214 kfree_skb_reason include/linux/skbuff.h:1279 [inline] kfree_skb include/linux/skbuff.h:1288 [inline] ip6_mc_input+0x9c3/0xbe0 net/ipv6/ip6_input.c:591 ip_sabotage_in+0x1de/0x270 net/bridge/br_netfilter_hooks.c:993 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc2/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:312 __netif_receive_skb_one_core net/core/dev.c:5887 [inline] __netif_receive_skb+0xd3/0x380 net/core/dev.c:6000 netif_receive_skb_internal net/core/dev.c:6086 [inline] netif_receive_skb+0x1cb/0x790 net/core/dev.c:6145 NF_HOOK+0x9d/0x390 include/linux/netfilter.h:315 br_handle_frame_finish+0x1489/0x1950 net/bridge/br_input.c:-1 br_nf_hook_thresh+0x3bf/0x490 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x948/0xd00 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:314 [inline] br_nf_pre_routing_ipv6+0x37e/0x6b0 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:282 [inline] br_handle_frame+0x97f/0x14c0 net/bridge/br_input.c:433 __netif_receive_skb_core+0x10de/0x4180 net/core/dev.c:5773 __netif_receive_skb_one_core net/core/dev.c:5885 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6000 process_backlog+0x60e/0x14f0 net/core/dev.c:6352 __napi_poll+0xc4/0x480 net/core/dev.c:7324 napi_poll net/core/dev.c:7388 [inline] net_rx_action+0x6ea/0xdf0 net/core/dev.c:7510 handle_softirqs+0x283/0x870 kernel/softirq.c:579 do_softirq+0xec/0x180 kernel/softirq.c:480 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407 spin_unlock_bh include/linux/spinlock.h:396 [inline] cfg80211_inform_single_bss_data+0x13d2/0x1ac0 net/wireless/scan.c:2383 cfg80211_inform_bss_data+0x1f6/0x3ad0 net/wireless/scan.c:3222 cfg80211_inform_bss_frame_data+0x362/0x700 net/wireless/scan.c:3317 ieee80211_bss_info_update+0x746/0x9e0 net/mac80211/scan.c:226 ieee80211_rx_bss_info net/mac80211/ibss.c:1102 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1581 [inline] ieee80211_ibss_rx_queued_mgmt+0xa36/0x2ae0 net/mac80211/ibss.c:1608 ieee80211_iface_process_skb net/mac80211/iface.c:1625 [inline] ieee80211_iface_work+0x806/0xfe0 net/mac80211/iface.c:1679 cfg80211_wiphy_work+0x2dc/0x460 net/wireless/core.c:435 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245