rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=4c7c/1/0x4000000000000000 softirq=12470/12471 fqs=0 rcu: (detected by 0, t=10505 jiffies, g=10997, q=60 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3523 Comm: kworker/u4:9 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:lookup_object lib/debugobjects.c:194 [inline] RIP: 0010:lookup_object_or_alloc lib/debugobjects.c:565 [inline] RIP: 0010:debug_object_activate+0x71/0x4b0 lib/debugobjects.c:711 Code: 48 0f af c8 48 c1 e9 2f 83 e1 f8 4c 8d a4 c9 60 73 04 97 48 8d bc c9 68 73 04 97 48 89 7c 24 20 e8 f4 e5 4a 06 48 89 44 24 18 <4c> 89 e0 48 c1 e8 03 42 80 3c 30 00 74 08 4c 89 e7 e8 a9 cc b6 fd RSP: 0018:ffffc900001f0ca8 EFLAGS: 00000046 RAX: 0000000000000802 RBX: ffff88807bfa7340 RCX: dffffc0000000000 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc900001f0b80 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200003e170 R12: ffffffff9711e700 R13: dffffc0000000000 R14: dffffc0000000000 R15: ffffffff8aacb180 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000600 CR3: 000000002b4aa000 CR4: 00000000003506e0 Call Trace: debug_hrtimer_activate kernel/time/hrtimer.c:450 [inline] debug_activate kernel/time/hrtimer.c:505 [inline] enqueue_hrtimer+0x30/0x370 kernel/time/hrtimer.c:1108 __run_hrtimer kernel/time/hrtimer.c:1767 [inline] __hrtimer_run_queues+0x637/0xc40 kernel/time/hrtimer.c:1814 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline] __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:unwind_next_frame+0xcd9/0x2970 arch/x86/kernel/unwind_orc.c:-1 Code: 85 07 1b 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 28 84 c0 48 8b 6c 24 10 48 8b 54 24 08 0f 85 08 1b 00 00 48 0f bf 03 48 01 c2 1c 01 00 00 e8 9d e0 4a 00 e9 5e 0c 00 00 e8 93 e0 4a 00 e9 b8 RSP: 0018:ffffc9000cc26f58 EFLAGS: 00000286 RAX: 0000000000000010 RBX: ffffffff8ecdd2b8 RCX: ffff88802dd73c00 RDX: ffffc9000cc27db8 RSI: ffffffff8cb9e760 RDI: 0000000000000004 RBP: ffffc9000cc27078 R08: ffff88802dd73c00 R09: 0000000000000008 R10: 0000000000000009 R11: 0000000000000000 R12: ffffc9000cc27028 R13: dffffc0000000000 R14: ffffffff8ecdd2b9 R15: ffffffff8ecdd2bc arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc+0xb4/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] cfg80211_inform_single_bss_frame_data net/wireless/scan.c:2953 [inline] cfg80211_inform_bss_frame_data+0x760/0x12b0 net/wireless/scan.c:3013 ieee80211_bss_info_update+0x70b/0x930 net/mac80211/scan.c:211 ieee80211_rx_bss_info net/mac80211/ibss.c:1124 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1613 [inline] ieee80211_ibss_rx_queued_mgmt+0x17c9/0x2ac0 net/mac80211/ibss.c:1642 ieee80211_iface_process_skb net/mac80211/iface.c:1651 [inline] ieee80211_iface_work+0x717/0xc70 net/mac80211/iface.c:1705 cfg80211_wiphy_work+0x225/0x260 net/wireless/core.c:437 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 rcu: rcu_preempt kthread starved for 10505 jiffies! g10997 f0x0 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:26568 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 schedule_timeout+0x160/0x280 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 34 Comm: kworker/u4:2 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0xddf/0x1130 kernel/smp.c:855 Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 6a d7 0a 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 a5 d3 0a 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 89 d3 RSP: 0018:ffffc90000aaf780 EFLAGS: 00000293 RAX: ffffffff817abd37 RBX: 1ffff110171e826d RCX: ffff8880182f9e00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000aaf900 R08: ffffffff90d94507 R09: 1ffffffff21b28a0 R10: dffffc0000000000 R11: fffffbfff21b28a1 R12: ffff8880b8f41368 R13: dffffc0000000000 R14: ffff8880b8e3d148 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff793146f98 CR3: 000000000cb30000 CR4: 00000000003506f0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1022 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2222 [inline] text_poke_bp_batch+0x318/0x930 arch/x86/kernel/alternative.c:2432 text_poke_flush arch/x86/kernel/alternative.c:2623 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2630 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x123/0x240 kernel/jump_label.c:207 static_key_enable+0x1a/0x20 kernel/jump_label.c:220 toggle_allocation_gate+0xaa/0x250 mm/kfence/core.c:831 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293