rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P2209/1:b..l P5839/1:b..l P1015/1:b..l rcu: (detected by 1, t=10502 jiffies, g=9561, q=308 ncpus=2) task:kworker/u8:7 state:R running task stack:23752 pid:1015 tgid:1015 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Call Trace: context_switch kernel/sched/core.c:5263 [inline] __schedule+0x1836/0x4ed0 kernel/sched/core.c:6871 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7198 irqentry_exit+0x5b5/0x640 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x16c/0x350 kernel/locking/lockdep.c:5872 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 c4 c1 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:ffffc90003f4f7e0 EFLAGS: 00000206 RAX: 437831db6a23af00 RBX: 0000000000000000 RCX: 437831db6a23af00 RDX: 0000000000000000 RSI: ffffffff8d974ed5 RDI: ffffffff8bbf8160 RBP: ffffffff8b243b70 R08: 0000000000000000 R09: ffffffff8b243b70 R10: dffffc0000000000 R11: ffffed100afc4017 R12: 0000000000000002 R13: ffffffff8df3d740 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:761 [inline] batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:833 [inline] batadv_iv_ogm_schedule+0x454/0xf00 net/batman-adv/bat_iv_ogm.c:873 batadv_iv_send_outstanding_bat_ogm_packet+0x6c6/0x7e0 net/batman-adv/bat_iv_ogm.c:1709 process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261 process_scheduled_works kernel/workqueue.c:3344 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 task:syz-executor state:R running task stack:21608 pid:5839 tgid:5839 ppid:5827 task_flags:0x400140 flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5263 [inline] __schedule+0x1836/0x4ed0 kernel/sched/core.c:6871 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7198 irqentry_exit+0x5b5/0x640 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_release+0x2ac/0x3d0 kernel/locking/lockdep.c:5893 Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 64 af d7 10 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc900040de7f0 EFLAGS: 00000206 RAX: 466879e098d63300 RBX: 0000000000000206 RCX: 466879e098d63300 RDX: 0000000000000003 RSI: ffffffff8d974ed5 RDI: ffffffff8bbf8160 RBP: ffff888032fc2a28 R08: ffffc900040de987 R09: 0000000000000000 R10: ffffc900040de978 R11: fffff5200081bd31 R12: 0000000000000003 R13: 0000000000000003 R14: ffffffff8df3d740 R15: ffff888032fc1e80 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:897 [inline] class_rcu_destructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680 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:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5652 [inline] __kmalloc_node_noprof+0x576/0x810 mm/slub.c:5658 kmalloc_array_node_noprof include/linux/slab.h:1075 [inline] alloc_slab_obj_exts+0x3e/0x100 mm/slub.c:2123 account_slab mm/slub.c:3202 [inline] allocate_slab+0x1cc/0x3b0 mm/slub.c:3267 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xf56/0x1990 mm/slub.c:4651 __slab_alloc+0x65/0x100 mm/slub.c:4774 __slab_alloc_node mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:5246 [inline] kmem_cache_alloc_lru_noprof+0x3fe/0x6e0 mm/slub.c:5277 alloc_inode+0x6a/0x1b0 fs/inode.c:346 new_inode+0x22/0x170 fs/inode.c:1175 debugfs_get_inode fs/debugfs/inode.c:72 [inline] __debugfs_create_file+0x14d/0x4f0 fs/debugfs/inode.c:442 debugfs_create_file_short+0x3f/0x60 fs/debugfs/inode.c:480 debugfs_hw_add+0x2aa/0x380 net/mac80211/debugfs.c:702 ieee80211_register_hw+0x34c7/0x4110 net/mac80211/main.c:1594 mac80211_hwsim_new_radio+0x2f76/0x5340 drivers/net/wireless/virtual/mac80211_hwsim.c:5810 hwsim_new_radio_nl+0xf5b/0x1bd0 drivers/net/wireless/virtual/mac80211_hwsim.c:6504 genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:746 __sys_sendto+0x3bd/0x520 net/socket.c:2248 __do_sys_sendto net/socket.c:2255 [inline] __se_sys_sendto net/socket.c:2251 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2251 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f288bd915dc RSP: 002b:00007ffe76991970 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f288cb14620 RCX: 00007f288bd915dc RDX: 0000000000000024 RSI: 00007f288cb14670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffe769919c4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f288cb14670 R15: 0000000000000000 task:kworker/u8:9 state:R running task stack:23608 pid:2209 tgid:2209 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events_unbound cfg80211_wiphy_work Call Trace: context_switch kernel/sched/core.c:5263 [inline] __schedule+0x1836/0x4ed0 kernel/sched/core.c:6871 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7198 irqentry_exit+0x5b5/0x640 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:60 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline] RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] RIP: 0010:unwind_next_frame+0xb5a/0x2390 arch/x86/kernel/unwind_orc.c:585 Code: 4c 24 20 0f b6 04 01 84 c0 0f 85 85 13 00 00 41 83 3e 00 0f 95 c0 49 39 df 0f 96 c1 20 c1 49 39 dc 0f 97 c0 20 c8 3c 01 75 18 <48> 8d 43 08 4c 39 f8 0f 97 c1 4c 39 e0 0f 96 c0 84 c1 0f 85 c2 00 RSP: 0018:ffffc90005486f98 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffffc90005487a78 RCX: 1ffff92000a90e01 RDX: ffffffff90a85066 RSI: 0000000000000002 RDI: ffffffff8bbf8100 RBP: 1ffff92000a90e0e R08: 0000000000000011 R09: ffffffff81742ff5 R10: ffffc900054870b8 R11: ffffffff81adaf40 R12: ffffc90005488000 R13: 1ffff92000a90e0f R14: ffffc90005487068 R15: ffffc90005480000 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:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5652 [inline] __kmalloc_noprof+0x41d/0x800 mm/slub.c:5664 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] ieee802_11_parse_elems_full+0x152/0x2ab0 net/mac80211/parse.c:1031 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2469 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1571 [inline] ieee80211_ibss_rx_queued_mgmt+0x48e/0x2b10 net/mac80211/ibss.c:1602 ieee80211_iface_process_skb net/mac80211/iface.c:1736 [inline] ieee80211_iface_work+0x85f/0x12d0 net/mac80211/iface.c:1790 cfg80211_wiphy_work+0x2ab/0x470 net/wireless/core.c:438 process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261 process_scheduled_works kernel/workqueue.c:3344 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 rcu: rcu_preempt kthread starved for 10653 jiffies! g9561 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:27712 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5263 [inline] __schedule+0x1836/0x4ed0 kernel/sched/core.c:6871 __schedule_loop kernel/sched/core.c:6953 [inline] schedule+0x165/0x360 kernel/sched/core.c:6968 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: 83 f1 02 00 cc cc cc 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 63 0f 0d 00 f3 0f 1e fa fb f4 58 f1 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6 RAX: cb024027e3f93300 RBX: ffffffff81979497 RCX: cb024027e3f93300 RDX: 0000000000000001 RSI: ffffffff8d78e538 RDI: ffffffff8bbf8160 RBP: ffffc90000197f10 R08: ffff8880b873339b R09: 1ffff110170e6673 R10: dffffc0000000000 R11: ffffed10170e6674 R12: ffffffff8f7de470 R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11003a50b70 FS: 0000000000000000(0000) GS:ffff888125fbc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b3140bff8 CR3: 000000001dad6000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x1e7/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x147