rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (3 ticks this GP) idle=f34c/1/0x4000000000000000 softirq=58006/58006 fqs=0 rcu: (detected by 0, t=10502 jiffies, g=50833, q=1125 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5827 Comm: syz-executor Not tainted 6.15.0-rc7-syzkaller-00083-gba5cb47b56e5 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x0/0x90 kernel/kcov.c:320 Code: 7c 11 10 48 89 74 11 18 48 89 44 11 20 e9 48 61 99 09 cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 e0 75 92 65 8b 15 68 e9 RSP: 0018:ffffc90000a08bf8 EFLAGS: 00000002 RAX: ffffffff89780940 RBX: 0000000000000004 RCX: ffff88802b75bc00 RDX: 0000000000010000 RSI: 0000000000000001 RDI: 0000000000000010 RBP: 0000000000000008 R08: ffff88805cb6b883 R09: 1ffff1100b96d710 R10: dffffc0000000000 R11: ffffed100b96d711 R12: 0000000000000001 R13: 0000000000000000 R14: ffff888144ab02e0 R15: ffff88805cb6b800 FS: 000055557cc05500(0000) GS:ffff8881261c2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055557cc205c8 CR3: 000000004e9c2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: taprio_set_budgets+0x122/0x3b0 net/sched/sch_taprio.c:666 advance_sched+0x963/0xc90 net/sched/sch_taprio.c:977 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x108/0x410 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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194 Code: 74 05 e8 fb 64 6e f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 e3 e6 37 f6 65 8b 05 6c d5 1c 07 85 c0 74 40 48 c7 04 24 0e 36 RSP: 0018:ffffc90004267ba0 EFLAGS: 00000206 RAX: e03c04202dd6d600 RBX: 0000000000000a06 RCX: e03c04202dd6d600 RDX: 0000000000000006 RSI: ffffffff8d74de43 RDI: 0000000000000001 RBP: ffffc90004267c28 R08: ffffffff8f7f3277 R09: 1ffffffff1efe64e R10: dffffc0000000000 R11: fffffbfff1efe64f R12: dffffc0000000000 R13: 1ffff11017127ee0 R14: ffff88813fffc180 R15: 1ffff9200084cf74 free_frozen_page_commit+0x4ba/0xff0 mm/page_alloc.c:2695 __free_frozen_pages+0x688/0xcd0 mm/page_alloc.c:2749 __slab_free+0x326/0x400 mm/slub.c:4553 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4147 [inline] slab_alloc_node mm/slub.c:4196 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4203 getname_flags+0xb8/0x540 fs/namei.c:146 getname include/linux/fs.h:2852 [inline] __do_sys_unlink fs/namei.c:4689 [inline] __se_sys_unlink fs/namei.c:4687 [inline] __x64_sys_unlink+0x3a/0x50 fs/namei.c:4687 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3b9098df17 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff10debbd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3b9098df17 RDX: 00007fff10debc00 RSI: 00007fff10debc90 RDI: 00007fff10debc90 RBP: 00007fff10debc90 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000206 R12: 00007fff10decd20 R13: 00007f3b90a1089d R14: 0000000000052991 R15: 00007fff10decd60 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g50833 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=26869 rcu: rcu_preempt kthread starved for 10502 jiffies! g50833 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:27032 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2046 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2248 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245