rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5187/1:b..l P5952/1:b..l rcu: (detected by 1, t=10502 jiffies, g=10197, q=489 ncpus=2) task:syz-executor state:R running task stack:23064 pid:5952 tgid:5952 ppid:5949 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_release+0x0/0x2d0 kernel/locking/lockdep.c:5876 Code: 24 18 4c 8b 54 24 10 44 8b 5c 24 0c eb 98 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 41 57 41 56 41 55 41 54 49 89 f4 53 48 89 fb 48 83 ec RSP: 0018:ffffc90003876e40 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffc90003877690 RCX: ffffc90003878001 RDX: 0000000000000000 RSI: ffffffff816cb9a4 RDI: ffffffff8e3c9620 RBP: 0000000000000001 R08: 0000000000000001 R09: 00000000c869dcb5 R10: 0000000000000002 R11: 000000000009c5b0 R12: ffffc90003876f08 R13: ffffc90003876eb8 R14: ffffc90003877690 R15: ffffc90003876eec 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+0x3f9/0x20a0 arch/x86/kernel/unwind_orc.c:479 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 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_lru_noprof+0x262/0x770 mm/slub.c:5282 __d_alloc+0x35/0xa80 fs/dcache.c:1730 d_alloc+0x4a/0x1e0 fs/dcache.c:1809 lookup_one_qstr_excl+0x175/0x250 fs/namei.c:1743 __start_dirop fs/namei.c:2866 [inline] start_dirop+0x59/0xb0 fs/namei.c:2875 simple_start_creating+0xf4/0x100 fs/libfs.c:2330 debugfs_start_creating.part.0+0x86/0x1c0 fs/debugfs/inode.c:394 debugfs_start_creating fs/debugfs/inode.c:371 [inline] __debugfs_create_file+0xb3/0x530 fs/debugfs/inode.c:428 debugfs_create_file_short+0x41/0x60 fs/debugfs/inode.c:471 add_common_files net/mac80211/debugfs_netdev.c:825 [inline] add_files net/mac80211/debugfs_netdev.c:945 [inline] ieee80211_debugfs_add_netdev net/mac80211/debugfs_netdev.c:1009 [inline] ieee80211_debugfs_recreate_netdev+0x4e6/0x17a0 net/mac80211/debugfs_netdev.c:1033 ieee80211_if_change_type+0x2ba/0x7a0 net/mac80211/iface.c:2050 ieee80211_change_iface+0xa5/0x500 net/mac80211/cfg.c:271 rdev_change_virtual_intf net/wireless/rdev-ops.h:74 [inline] cfg80211_change_iface+0x55d/0xce0 net/wireless/util.c:1217 nl80211_set_interface+0x8e0/0xc80 net/wireless/nl80211.c:4638 genl_family_rcv_msg_doit+0x209/0x2f0 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x158/0x420 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+0x5aa/0x870 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] __sys_sendto+0x4a3/0x520 net/socket.c:2206 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f765e1915dc RSP: 002b:00007ffe213870c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f765ef14620 RCX: 00007f765e1915dc RDX: 0000000000000024 RSI: 00007f765ef14670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffe21387114 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f765ef14670 R15: 0000000000000000 task:udevd state:R running task stack:26360 pid:5187 tgid:5187 ppid:1 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7047 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/0x5d0 net/core/sock.c:3611 __netlink_sendskb net/netlink/af_netlink.c:1263 [inline] netlink_sendskb net/netlink/af_netlink.c:1269 [inline] netlink_unicast+0x75f/0x870 net/netlink/af_netlink.c:1359 netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2646 __sys_sendmsg+0x16d/0x220 net/socket.c:2678 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcea62a7407 RSP: 002b:00007ffd391fa3b0 EFLAGS: 00000202 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fcea6977880 RCX: 00007fcea62a7407 RDX: 0000000000000000 RSI: 00007ffd391fa410 RDI: 0000000000000004 RBP: 000056339ab1fbb0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000000b3 R13: 000056339a89bd80 R14: 0000000000000000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10582 jiffies! g10197 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:29112 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 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+0x983/0xb10 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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 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+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: c6 5f 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 13 59 12 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff8e007df8 EFLAGS: 000002c6 RAX: 0000000000123833 RBX: 0000000000000000 RCX: ffffffff8b7806d9 RDX: 0000000000000000 RSI: ffffffff8dacdb69 RDI: ffffffff8bf2b380 RBP: fffffbfff1c12f68 R08: 0000000000000001 R09: ffffed101708673d R10: ffff8880b84339eb R11: ffffffff8e098670 R12: 0000000000000000 R13: ffffffff8e097b40 R14: ffffffff9088afd0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881248f6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000035e38000 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:191 [inline] do_idle+0x38d/0x510 kernel/sched/idle.c:332 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 rest_init+0x16b/0x2b0 init/main.c:757 start_kernel+0x3ef/0x4d0 init/main.c:1206 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x148