rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (2 ticks this GP) idle=fd2c/1/0x4000000000000000 softirq=8536/8536 fqs=1 rcu: (detected by 1, t=10502 jiffies, g=7961, q=182 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5471 Comm: syz-executor.0 Not tainted 6.10.0-rc4-syzkaller-00198-gbab4923132fe #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:instrument_atomic_read include/linux/instrumented.h:68 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] RIP: 0010:__lock_acquire+0xc53/0x1fd0 kernel/locking/lockdep.c:5107 Code: 04 38 84 c0 0f 85 aa 0c 00 00 83 3d f6 7e 07 13 00 75 39 48 63 9c 24 88 00 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 80 75 fa 92 08 00 00 00 e8 b3 64 89 00 48 bf 00 00 00 00 00 fc ff df 48 0f RSP: 0018:ffffc900000077f0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff9479f603 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff92fa7580 RBP: ffff88802aa92958 R08: ffffffff92fa7587 R09: 1ffffffff25f4eb0 R10: dffffc0000000000 R11: fffffbfff25f4eb1 R12: 0000000000000001 R13: ffff88802aa91e00 R14: 1ffff1100555252f R15: ffff88802aa92978 FS: 00007f6473f006c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f64733a8000 CR3: 0000000079780000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 debug_objects_fill_pool+0x9f/0x9b0 lib/debugobjects.c:614 debug_object_activate+0x135/0x510 lib/debugobjects.c:704 debug_hrtimer_activate kernel/time/hrtimer.c:423 [inline] debug_activate kernel/time/hrtimer.c:478 [inline] enqueue_hrtimer+0x30/0x3c0 kernel/time/hrtimer.c:1085 __run_hrtimer kernel/time/hrtimer.c:1704 [inline] __hrtimer_run_queues+0x6cb/0xd50 kernel/time/hrtimer.c:1751 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1813 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 de 46 6b f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 c3 07 d5 f5 65 8b 05 34 41 73 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc900041deb20 EFLAGS: 00000206 RAX: c5e0aaa8e95f5100 RBX: 1ffff9200083bd68 RCX: ffffffff8172d80a RDX: dffffc0000000000 RSI: ffffffff8bcabb80 RDI: 0000000000000001 RBP: ffffc900041debb0 R08: ffffffff92fa7687 R09: 1ffffffff25f4ed0 R10: dffffc0000000000 R11: fffffbfff25f4ed1 R12: dffffc0000000000 R13: 1ffff9200083bd64 R14: ffffc900041deb40 R15: 0000000000000246 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] taprio_change+0x270d/0x4430 net/sched/sch_taprio.c:1970 taprio_init+0x9da/0xc80 net/sched/sch_taprio.c:2111 qdisc_create+0x9d4/0x11a0 net/sched/sch_api.c:1355 tc_modify_qdisc+0xa26/0x1e40 net/sched/sch_api.c:1777 rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2585 ___sys_sendmsg net/socket.c:2639 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f647327dda9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6473f000c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f64733abf80 RCX: 00007f647327dda9 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000004 RBP: 00007f64732ca47a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f64733abf80 R15: 00007fff53437ab8 rcu: rcu_preempt kthread starved for 10495 jiffies! g7961 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:26448 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2000 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2202 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 2434 Comm: kworker/u8:9 Not tainted 6.10.0-rc4-syzkaller-00198-gbab4923132fe #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0x1860/0x29d0 kernel/smp.c:855 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 f9 09 0c 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 a4 05 0c 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 88 05 RSP: 0018:ffffc9000938f700 EFLAGS: 00000293 RAX: ffffffff818a2008 RBX: 1ffff11017288c01 RCX: ffff888029c93c00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000938f8e0 R08: ffffffff818a1fd7 R09: 1ffffffff25f4eb0 R10: dffffc0000000000 R11: fffffbfff25f4eb1 R12: dffffc0000000000 R13: ffff8880b9446008 R14: ffff8880b953f8c0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005564cab53950 CR3: 000000000e132000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1023 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2069 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2279 text_poke_flush arch/x86/kernel/alternative.c:2470 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2477 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:826 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244