rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P14234/1:b..l P5222/1:b..l rcu: (detected by 0, t=10503 jiffies, g=84885, q=265 ncpus=2) task:udevd state:R running task stack:20976 pid:5222 tgid:5222 ppid:1 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5327 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6707 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6886 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6910 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x130/0x140 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __wake_up_common_lock+0x18c/0x1e0 kernel/sched/wait.c:108 sock_def_readable+0x20f/0x5b0 net/core/sock.c:3447 __netlink_sendskb net/netlink/af_netlink.c:1278 [inline] netlink_sendskb+0x9e/0x140 net/netlink/af_netlink.c:1284 netlink_unicast+0x39d/0x990 net/netlink/af_netlink.c:1372 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:744 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2609 ___sys_sendmsg net/socket.c:2663 [inline] __sys_sendmsg+0x292/0x380 net/socket.c:2692 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: 0033:0x7f3164d24a4b RSP: 002b:00007fffa2449f68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000055f90358d9e0 RCX: 00007f3164d24a4b RDX: 0000000000000000 RSI: 00007fffa2449f78 RDI: 0000000000000004 RBP: 000055f9035950a0 R08: 0000000000000001 R09: 0000000000000000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000000a9 R14: 0000000000000000 R15: 0000000000000000 task:syz-executor state:R running task stack:20688 pid:14234 tgid:14234 ppid:14213 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5327 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6707 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6886 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6910 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] copy_pte_range mm/memory.c:1200 [inline] copy_pmd_range+0x74ac/0x7ee0 mm/memory.c:1261 copy_pud_range mm/memory.c:1298 [inline] copy_p4d_range mm/memory.c:1322 [inline] copy_page_range+0x99f/0xe90 mm/memory.c:1420 dup_mmap kernel/fork.c:745 [inline] dup_mm kernel/fork.c:1672 [inline] copy_mm+0x122b/0x1f60 kernel/fork.c:1721 copy_process+0x1845/0x3d50 kernel/fork.c:2371 kernel_clone+0x226/0x8f0 kernel/fork.c:2783 __do_sys_clone kernel/fork.c:2926 [inline] __se_sys_clone kernel/fork.c:2910 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2910 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: 0033:0x7fcd77974f93 RSP: 002b:00007ffff7a18cb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fcd77974f93 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 000055557dfaf7d0 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000015ddfe R14: 000000000015d500 R15: 00007ffff7a18e40 rcu: rcu_preempt kthread timer wakeup didn't happen for 10502 jiffies! g84885 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=98232 rcu: rcu_preempt kthread starved for 10503 jiffies! g84885 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:25616 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5327 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6707 __schedule_loop kernel/sched/core.c:6784 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6799 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 19 Comm: rcu_exp_gp_kthr Not tainted 6.12.0-rc5-next-20241101-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:taprio_set_budgets+0x24e/0x370 net/sched/sch_taprio.c:664 Code: 00 00 fc ff df 0f b6 04 08 84 c0 75 31 41 89 2e 4c 39 64 24 20 0f 84 e8 00 00 00 e8 6c 29 cd f7 49 83 c5 08 48 83 44 24 18 08 <49> 83 c4 04 49 ff c7 49 89 de 48 8b 5c 24 08 e9 9d fe ff ff 44 89 RSP: 0018:ffffc90000a18c30 EFLAGS: 00000082 RAX: ffffffff89c89494 RBX: ffff8880281d6c00 RCX: ffff88801cadbc00 RDX: 0000000000010000 RSI: 0000000000000004 RDI: ffff8880281d6c80 RBP: 0000000000000000 R08: ffff8880281d6c83 R09: 1ffff1100503ad90 R10: dffffc0000000000 R11: ffffed100503ad91 R12: 0000000000000000 R13: ffff8880281d6c08 R14: ffff8880281d6c80 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020003c80 CR3: 0000000063850000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: advance_sched+0x98d/0xca0 net/sched/sch_taprio.c:977 __run_hrtimer kernel/time/hrtimer.c:1691 [inline] __hrtimer_run_queues+0x59b/0xd50 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5201 Code: c9 50 e8 29 05 0c 00 48 83 c4 08 4c 89 f7 e8 4d 39 00 00 0f 1f 44 00 00 4c 89 f7 e8 e0 75 69 0a e8 9b 99 38 00 fb 48 8b 5d c0 <48> 8d bb f8 15 00 00 48 89 f8 48 c1 e8 03 49 be 00 00 00 00 00 fc RSP: 0018:ffffc90000187b68 EFLAGS: 00000286 RAX: 21f8c21ee861e400 RBX: ffff88801cadbc00 RCX: ffffffff9a3d8903 RDX: dffffc0000000000 RSI: ffffffff8c0ad520 RDI: ffffffff8c6054c0 RBP: ffffc90000187bb0 R08: ffffffff901d0fb7 R09: 1ffffffff203a1f6 R10: dffffc0000000000 R11: fffffbfff203a1f7 R12: 1ffff110170e7eb4 R13: dffffc0000000000 R14: ffff8880b873e780 R15: ffff8880b873f5a0 context_switch kernel/sched/core.c:5330 [inline] __schedule+0x1857/0x4c30 kernel/sched/core.c:6707 __schedule_loop kernel/sched/core.c:6784 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6799 kthread_worker_fn+0x486/0xb70 kernel/kthread.c:851 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