rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (1 GPs behind) idle=3cb/1/0x4000000000000000 softirq=11089/11095 fqs=4370 (t=10500 jiffies g=12925 q=1255) NMI backtrace for cpu 0 CPU: 0 PID: 5855 Comm: syz.3.481 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_dump_cpu_stacks+0x22f/0x380 kernel/rcu/tree_stall.h:349 print_cpu_stall+0x31d/0x5f0 kernel/rcu/tree_stall.h:633 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline] rcu_pending kernel/rcu/tree.c:3936 [inline] rcu_sched_clock_irq+0x6ea/0x1120 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:2021 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4b4/0xb70 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194 Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 2f 8a 8c f7 65 8b 05 d0 97 3c 76 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc90000007720 EFLAGS: 00000206 RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: bbaae5e77fc71600 RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: 0000000000000001 RBP: ffffc900000077b8 R08: ffffffff901d418f R09: 1ffffffff203a831 R10: dffffc0000000000 R11: fffffbfff203a832 R12: dffffc0000000000 R13: ffff88807c758000 R14: ffffffff964c3e78 R15: 1ffff92000000ee4 __debug_check_no_obj_freed lib/debugobjects.c:982 [inline] debug_check_no_obj_freed+0x515/0x530 lib/debugobjects.c:1003 free_pages_prepare mm/page_alloc.c:1345 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x237/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396 put_page include/linux/mm.h:1258 [inline] __skb_frag_unref include/linux/skbuff.h:3254 [inline] skb_release_data+0x3b1/0x800 net/core/skbuff.c:672 skb_release_all net/core/skbuff.c:742 [inline] __kfree_skb+0x4c/0x60 net/core/skbuff.c:756 tcp_write_queue_purge+0x13d/0x3e0 net/ipv4/tcp.c:2967 tcp_done_with_error+0x3f/0xc0 net/ipv4/tcp_input.c:4400 tcp_write_err net/ipv4/tcp_timer.c:70 [inline] tcp_write_timeout net/ipv4/tcp_timer.c:273 [inline] tcp_retransmit_timer+0x1195/0x2540 net/ipv4/tcp_timer.c:543 tcp_write_timer_handler+0x205/0x9a0 net/ipv4/tcp_timer.c:655 tcp_write_timer+0x126/0x280 net/ipv4/tcp_timer.c:675 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648 expire_timers kernel/time/timer.c:1699 [inline] __run_timers+0x53e/0x800 kernel/time/timer.c:1970 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983 handle_softirqs+0x339/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x9d/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 RIP: 0010:finish_lock_switch+0x134/0x280 kernel/sched/core.c:4804 Code: be ff ff ff ff e8 6c 01 68 08 85 c0 74 4a 4d 85 ff 75 66 0f 1f 44 00 00 48 89 df e8 16 6d 71 08 e8 f1 e2 2a 00 fb 48 83 c4 08 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 c9 09 fe ff 43 80 3c RSP: 0018:ffffc9000320e328 EFLAGS: 00000286 RAX: bbaae5e77fc71600 RBX: ffff8880b903a340 RCX: bbaae5e77fc71600 RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f980 RBP: 1ffff11017207613 R08: ffffffff901d412f R09: 1ffffffff203a825 R10: dffffc0000000000 R11: fffffbfff203a826 R12: 1ffff110172075c1 R13: dffffc0000000000 R14: ffff8880b903ae08 R15: 0000000000000000 finish_task_switch+0x12f/0x640 kernel/sched/core.c:4921 context_switch kernel/sched/core.c:5052 [inline] __schedule+0x11f7/0x43c0 kernel/sched/core.c:6395 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6799 irqentry_exit+0x63/0x70 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:put_cpu_partial+0x15e/0x190 mm/slub.c:2591 Code: 00 00 48 3b 44 24 08 75 4d 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 3f aa fe 07 41 f7 c5 00 02 00 00 74 c3 fb 4d 85 ff <75> c2 eb cb 48 c7 c7 d0 21 3f 8c 4c 89 e6 e8 5f 34 46 02 e9 e5 fe RSP: 0018:ffffc9000320e718 EFLAGS: 00000246 RAX: bbaae5e77fc71600 RBX: ffff888016c418c0 RCX: bbaae5e77fc71600 RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f980 RBP: 0000000000000001 R08: ffffffff901d412f R09: 1ffffffff203a825 R10: dffffc0000000000 R11: fffffbfff203a826 R12: 0000000000000000 R13: 0000000000000286 R14: ffff8880b903de20 R15: 0000000000000000 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x100/0x290 mm/slub.c:3238 kmem_cache_zalloc include/linux/slab.h:728 [inline] __kernfs_new_node+0xe3/0x6c0 fs/kernfs/dir.c:593 kernfs_new_node+0x148/0x250 fs/kernfs/dir.c:669 __kernfs_create_file+0x47/0x2e0 fs/kernfs/file.c:985 sysfs_add_file_mode_ns+0x2d4/0x3a0 fs/sysfs/file.c:317 create_files fs/sysfs/group.c:64 [inline] internal_create_group+0x495/0xd00 fs/sysfs/group.c:149 internal_create_groups fs/sysfs/group.c:189 [inline] sysfs_create_groups+0x55/0x120 fs/sysfs/group.c:215 device_add_groups drivers/base/core.c:2491 [inline] device_add_attrs+0x83/0x6a0 drivers/base/core.c:2639 device_add+0x64b/0xfb0 drivers/base/core.c:3363 netdev_register_kobject+0x184/0x320 net/core/net-sysfs.c:2014 register_netdevice+0x1042/0x1710 net/core/dev.c:10423 cfg80211_register_netdevice+0x155/0x2f0 net/wireless/core.c:1426 ieee80211_if_add+0x1022/0x1dc0 net/mac80211/iface.c:2078 ieee80211_register_hw+0x2bde/0x3af0 net/mac80211/main.c:1323 mac80211_hwsim_new_radio+0x20d3/0x4080 drivers/net/wireless/mac80211_hwsim.c:3374 hwsim_new_radio_nl+0xa6f/0xc40 drivers/net/wireless/mac80211_hwsim.c:3950 genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline] genl_family_rcv_msg net/netlink/genetlink.c:775 [inline] genl_rcv_msg+0xcea/0xf90 net/netlink/genetlink.c:792 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2507 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2445 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2499 __sys_sendmsg net/socket.c:2528 [inline] __do_sys_sendmsg net/socket.c:2537 [inline] __se_sys_sendmsg+0x1af/0x290 net/socket.c:2535 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f3570140819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f356e39a028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f35703b9fa0 RCX: 00007f3570140819 RDX: 0000000000000000 RSI: 0000200000000000 RDI: 000000000000000d RBP: 00007f35701d6c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f35703ba038 R14: 00007f35703b9fa0 R15: 00007ffda0f1a3a8