rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P63/1:b..l P6068/1:b..l P5229/1:b..l P1092/1:b..l P5524/1:b..l rcu: (detected by 1, t=10502 jiffies, g=11593, q=677453 ncpus=2) task:dhcpcd state:R running task stack:21352 pid:5524 tgid:5524 ppid:5523 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:deref_stack_reg+0x1a2/0x230 arch/x86/kernel/unwind_orc.c:406 Code: ca 80 fa 01 75 46 49 8d 40 08 48 39 d8 0f 97 c1 4c 39 f0 0f 96 c0 20 c8 3c 01 75 30 4c 89 c7 49 89 f7 e8 11 08 00 00 49 89 c6 <48> 8b 5c 24 18 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df RSP: 0018:ffffc90003a1f780 EFLAGS: 00000202 RAX: 0000000000000dc0 RBX: ffffc90003a18000 RCX: 0000000000000001 RDX: ffffc90003a1f8e8 RSI: dffffc0000000000 RDI: ffffc90003a1fc40 RBP: 1ffff92000743f15 R08: ffffc90003a1fc40 R09: ffffc90003a1f8f8 R10: dffffc0000000000 R11: fffff52000743f21 R12: 1ffff92000743f16 R13: 1ffff92000743f17 R14: 0000000000000dc0 R15: dffffc0000000000 unwind_next_frame+0x17c4/0x2390 arch/x86/kernel/unwind_orc.c:-1 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 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236 lsm_file_alloc security/security.c:733 [inline] security_file_alloc+0x34/0x330 security/security.c:2888 init_file+0x93/0x2f0 fs/file_table.c:159 alloc_empty_file+0x6e/0x1d0 fs/file_table.c:241 alloc_file fs/file_table.c:354 [inline] alloc_file_pseudo+0x13d/0x210 fs/file_table.c:383 sock_alloc_file+0xb8/0x2e0 net/socket.c:470 __sys_socketpair+0x2db/0x560 net/socket.c:1818 __do_sys_socketpair net/socket.c:1847 [inline] __se_sys_socketpair net/socket.c:1844 [inline] __x64_sys_socketpair+0x9b/0xb0 net/socket.c:1844 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc63f55f73a RSP: 002b:00007ffc3db6bbb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000035 RAX: ffffffffffffffda RBX: 00005616baaffbf0 RCX: 00007fc63f55f73a RDX: 0000000000000000 RSI: 0000000000080805 RDI: 0000000000000001 RBP: 00007ffc3db8bfe0 R08: 0000000000000000 R09: 0000000000000001 R10: 00007ffc3db6bbd0 R11: 0000000000000246 R12: 00007ffc3db6bbd0 R13: 0000000000000001 R14: 0000000000000000 R15: 00005616b82bbac0 task:kworker/u8:5 state:R running task stack:24072 pid:1092 tgid:1092 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events_unbound cfg80211_wiphy_work Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_release+0x2b5/0x3e0 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 0b 0f 03 11 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc90003dce570 EFLAGS: 00000206 RAX: 2b773e6004377700 RBX: 0000000000000202 RCX: 2b773e6004377700 RDX: 0000000000000003 RSI: ffffffff8dba7f2b RDI: ffffffff8be33880 RBP: ffff8880268b8b68 R08: ffffc90003dcf9a0 R09: ffffc90003dce6f8 R10: dffffc0000000000 R11: fffff520007b9ce1 R12: 0000000000000003 R13: 0000000000000003 R14: ffffffff8e139f20 R15: ffff8880268b8000 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [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 save_stack+0xf5/0x1f0 mm/page_owner.c:156 __set_page_owner+0x8d/0x4a0 mm/page_owner.c:329 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2655 new_slab mm/slub.c:2709 [inline] ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891 __slab_alloc mm/slub.c:3981 [inline] __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] __do_kmalloc_node mm/slub.c:4364 [inline] __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4377 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] cfg80211_inform_single_bss_data+0x905/0x1ac0 net/wireless/scan.c:2351 cfg80211_inform_bss_data+0x1fb/0x3b30 net/wireless/scan.c:3234 cfg80211_inform_bss_frame_data+0x3d7/0x730 net/wireless/scan.c:3325 ieee80211_bss_info_update+0x746/0x9e0 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+0xa36/0x2ae0 net/mac80211/ibss.c:1600 ieee80211_iface_process_skb net/mac80211/iface.c:1699 [inline] ieee80211_iface_work+0x85f/0x12d0 net/mac80211/iface.c:1753 cfg80211_wiphy_work+0x2bb/0x470 net/wireless/core.c:435 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 task:udevd state:R running task stack:25288 pid:5229 tgid:5229 ppid:1 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__kasan_check_byte+0x14/0x40 mm/kasan/common.c:567 Code: ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 41 56 53 48 89 f3 49 89 fe e8 5e 14 00 00 84 c0 <75> 16 be 01 00 00 00 4c 89 f7 31 d2 48 89 d9 89 c3 e8 c6 03 00 00 RSP: 0018:ffffc900039efc08 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffffff825d47a8 RCX: 0fe30b4a63809000 RDX: 0000000000000000 RSI: ffffffff825d47a8 RDI: 1ffffffff1c273e4 RBP: ffffffff825d478c R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed10042f71e1 R12: 0000000000000002 R13: ffffffff8e139f20 R14: ffffffff8e139f20 R15: 0000000000000000 kasan_check_byte include/linux/kasan.h:399 [inline] lock_acquire+0x8d/0x360 kernel/locking/lockdep.c:5842 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] kernfs_root+0x38/0x230 fs/kernfs/kernfs-internal.h:75 kernfs_root_is_locked fs/kernfs/kernfs-internal.h:109 [inline] kernfs_rcu_name fs/kernfs/kernfs-internal.h:119 [inline] kernfs_fop_readdir+0x38e/0x870 fs/kernfs/dir.c:1901 iterate_dir+0x399/0x570 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:410 [inline] __se_sys_getdents64+0xe4/0x260 fs/readdir.c:396 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f13a0ef0d23 RSP: 002b:00007ffed5f15f28 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 000056489d98c1a0 RCX: 00007f13a0ef0d23 RDX: 0000000000008000 RSI: 000056489d98c1d0 RDI: 000000000000000d RBP: 000056489d98c1a4 R08: 00007f13a0ff1ac0 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000293 R12: 000056489d98c1d0 R13: fffffffffffffe68 R14: 0000000000000002 R15: 00007ffed5f16210 task:kworker/u8:11 state:R running task stack:24744 pid:6068 tgid:6068 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events_unbound cfg80211_wiphy_work Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x175/0x360 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 7b 21 03 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc900050170f8 EFLAGS: 00000206 RAX: 60f01a527fde9300 RBX: 0000000000000000 RCX: 60f01a527fde9300 RDX: 0000000000000000 RSI: ffffffff8dba7f2b RDI: ffffffff8be33880 RBP: ffffffff8172c195 R08: 0000000000000000 R09: ffffffff8172c195 R10: dffffc0000000000 R11: fffff52000a02e65 R12: 0000000000000002 R13: ffffffff8e139f20 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 __unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24 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:243 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kfree+0x18e/0x440 mm/slub.c:4879 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1574 [inline] ieee80211_ibss_rx_queued_mgmt+0x11ef/0x2ae0 net/mac80211/ibss.c:1600 ieee80211_iface_process_skb net/mac80211/iface.c:1699 [inline] ieee80211_iface_work+0x85f/0x12d0 net/mac80211/iface.c:1753 cfg80211_wiphy_work+0x2bb/0x470 net/wireless/core.c:435 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 task:kworker/u8:4 state:R running task stack:22232 pid:63 tgid:63 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events_unbound cfg80211_wiphy_work Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__kasan_check_byte+0x2d/0x40 mm/kasan/common.c:572 Code: 00 41 56 53 48 89 f3 49 89 fe e8 5e 14 00 00 84 c0 75 16 be 01 00 00 00 4c 89 f7 31 d2 48 89 d9 89 c3 e8 c6 03 00 00 89 d8 5b <41> 5e e9 67 4b ed fe cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 RSP: 0018:ffffc9000211f148 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ff379ad44d0afe00 RDX: 0000000000000000 RSI: ffffffff8172c1b2 RDI: 1ffffffff1c273e4 RBP: ffffffff8172c195 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff81ac3ae0 R12: 0000000000000002 R13: ffffffff8e139f20 R14: ffffffff8e139f20 R15: 0000000000000000 kasan_check_byte include/linux/kasan.h:399 [inline] lock_acquire+0x8d/0x360 kernel/locking/lockdep.c:5842 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 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:243 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kfree+0x18e/0x440 mm/slub.c:4879 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1574 [inline] ieee80211_ibss_rx_queued_mgmt+0x11ef/0x2ae0 net/mac80211/ibss.c:1600 ieee80211_iface_process_skb net/mac80211/iface.c:1699 [inline] ieee80211_iface_work+0x85f/0x12d0 net/mac80211/iface.c:1753 cfg80211_wiphy_work+0x2bb/0x470 net/wireless/core.c:435 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: rcu_preempt kthread starved for 10673 jiffies! g11593 f0x2 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:27160 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 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+0x3fc/0x770 arch/x86/kernel/process.c:148 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 07/12/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: 3e 6d 96 f5 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 73 57 0e 00 f3 0f 1e fa fb f4 13 6d 96 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197de0 EFLAGS: 000002c2 RAX: d8adf05943907a00 RBX: ffffffff819683f8 RCX: d8adf05943907a00 RDX: 0000000000000001 RSI: ffffffff8d9b8acb RDI: ffffffff8be33880 RBP: ffffc90000197f20 R08: ffff8880b8732f9b R09: 1ffff110170e65f3 R10: dffffc0000000000 R11: ffffed10170e65f4 R12: ffffffff8fa39630 R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110039d9b40 FS: 0000000000000000(0000) GS:ffff888125d18000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc3db8c380 CR3: 0000000055730000 CR4: 0000000000350ef0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x74/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x1e8/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x147