rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6682/1:b..l P5183/1:b..l rcu: (detected by 1, t=10502 jiffies, g=20205, q=492 ncpus=2) task:udevd state:R running task stack:24728 pid:5183 tgid:5183 ppid:1 task_flags:0x400140 flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6929 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7113 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x61/0x80 kernel/locking/spinlock.c:194 sock_def_readable+0x15b/0x600 net/core/sock.c:3551 __netlink_sendskb net/netlink/af_netlink.c:1265 [inline] netlink_sendskb net/netlink/af_netlink.c:1271 [inline] netlink_unicast+0x75f/0x870 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa98/0xc70 net/socket.c:2630 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2684 __sys_sendmsg+0x16d/0x220 net/socket.c:2716 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7d19ca7407 RSP: 002b:00007ffc089dac00 EFLAGS: 00000202 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f7d1a3f9880 RCX: 00007f7d19ca7407 RDX: 0000000000000000 RSI: 00007ffc089dac60 RDI: 0000000000000004 RBP: 000055abef625870 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000000b3 R13: 000055abef109d80 R14: 0000000000000000 R15: 0000000000000000 task:kworker/u8:13 state:R running task stack:25592 pid:6682 tgid:6682 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events_unbound cfg80211_wiphy_work Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6929 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7256 irqentry_exit+0x36/0x90 kernel/entry/common.c:211 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:unwind_next_frame+0x5fc/0x20a0 arch/x86/kernel/unwind_orc.c:517 Code: 00 00 0f 87 20 02 00 00 41 80 fe 04 0f 84 c7 0b 00 00 41 80 fe 05 0f 85 cf 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 14 24 <48> c1 ea 03 80 3c 02 00 0f 85 0c 17 00 00 48 89 c8 4d 8b 7d 38 48 RSP: 0018:ffffc9001be86df8 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffffff912608bc RDX: ffffc9001be86ea0 RSI: 0000000000000001 RDI: ffffffff909dbd1c RBP: ffffc9001be86eb0 R08: ffffffff912608c0 R09: 0000000000000000 R10: 0000000000000000 R11: 000000000001258a R12: ffffc9001be86eb8 R13: ffffc9001be86e68 R14: 0000000000000005 R15: 0000000000000000 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5627 [inline] __kmalloc_noprof+0x32f/0x880 mm/slub.c:5639 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] cfg80211_inform_single_bss_data+0x53e/0x1df0 net/wireless/scan.c:2357 cfg80211_inform_bss_data+0x22b/0x3be0 net/wireless/scan.c:3240 cfg80211_inform_bss_frame_data+0x26f/0x750 net/wireless/scan.c:3331 ieee80211_bss_info_update+0x310/0xab0 net/mac80211/scan.c:226 ieee80211_rx_bss_info net/mac80211/ibss.c:1094 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1573 [inline] ieee80211_ibss_rx_queued_mgmt+0x191b/0x2fe0 net/mac80211/ibss.c:1600 ieee80211_iface_process_skb net/mac80211/iface.c:1694 [inline] ieee80211_iface_work+0xe2e/0x1360 net/mac80211/iface.c:1748 cfg80211_wiphy_work+0x2c7/0x580 net/wireless/core.c:435 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: rcu_preempt kthread starved for 9882 jiffies! g20205 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:28120 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7026 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 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: 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 10/02/2025 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 97 74 02 c3 cc cc cc cc 0f 1f 00 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 43 95 23 00 fb f4 3c 0a 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197de8 EFLAGS: 000002c6 RAX: 0000000000e6a993 RBX: 0000000000000001 RCX: ffffffff8b6692a9 RDX: 0000000000000000 RSI: ffffffff8db03f46 RDI: ffffffff8bf1ea40 RBP: ffffed1003adb490 R08: 0000000000000001 R09: ffffed10170a6655 R10: ffff8880b85332ab R11: 0000000000000001 R12: 0000000000000001 R13: ffff88801d6da480 R14: ffffffff908339d0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124ad6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feeab2156c8 CR3: 0000000077b8a000 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+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x38d/0x500 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148