sched: DL replenish lagged too much rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6141/1:b..l rcu: (detected by 1, t=10503 jiffies, g=16841, q=1803 ncpus=2) task:syz.1.107 state:R running task stack:25640 pid:6141 tgid:6141 ppid:5650 task_flags:0x40004c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7556 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:lock_release+0x2d7/0x3c0 kernel/locking/lockdep.c:5893 Code: 1d ca 11 00 00 00 00 eb b5 e8 c5 dd 2d 0a f7 c3 00 02 00 00 74 b9 65 48 8b 05 b5 d8 c9 11 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 9a de 30 0a cc 48 8d 3d 52 e0 b7 RSP: 0018:ffffc9000741f4a8 EFLAGS: 00000282 RAX: 7ef1f4b364211b00 RBX: 0000000000000206 RCX: 0000000000000046 RDX: 0000000000000001 RSI: ffffffff8e4b3728 RDI: ffffffff8c4bdb80 RBP: ffff888028148bc8 R08: ffffc9000741f920 R09: 0000000000000000 R10: ffffc9000741f5d8 R11: fffff52000e83ebd R12: 0000000000000001 R13: 0000000000000001 R14: ffffffff8eb59c60 R15: ffff888028148000 rcu_lock_release include/linux/rcupdate.h:310 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1183 [inline] unwind_next_frame+0x1baa/0x2550 arch/x86/kernel/unwind_orc.c:709 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x32d/0x660 mm/slub.c:5515 _kmalloc_noprof include/linux/slab.h:969 [inline] slab_free_hook mm/slub.c:2657 [inline] slab_free mm/slub.c:6405 [inline] kmem_cache_free+0x156/0x650 mm/slub.c:6532 tear_down_vmas+0x312/0x520 mm/mmap.c:1262 exit_mmap+0x4ca/0x9f0 mm/mmap.c:1320 __mmput+0x118/0x420 kernel/fork.c:1187 exit_mm+0x221/0x2d0 kernel/exit.c:615 do_exit+0x6cd/0x2360 kernel/exit.c:997 do_group_exit+0x22d/0x2f0 kernel/exit.c:1152 __do_sys_exit_group kernel/exit.c:1163 [inline] __se_sys_exit_group kernel/exit.c:1161 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1161 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4b9c99de99 RSP: 002b:00007ffe955fea88 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4b9c99de99 RDX: 00007f4b9bbf9000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffe955feaec R08: 0000000000000000 R09: 00000000000927c0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000017 R13: 00000000000927c0 R14: 00000000000223d4 R15: 00007ffe955feb40 rcu: rcu_preempt kthread starved for 2392 jiffies! g16841 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:27496 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 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: 1318 Comm: aoe_tx0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:__lock_acquire+0x694/0x2cf0 kernel/locking/lockdep.c:5207 Code: 00 18 00 0f 84 bb 00 00 00 4c 89 f7 4c 89 ee ba 08 00 00 00 e8 8d 44 00 00 31 ed 85 c0 0f 84 19 0d 00 00 83 3d 4c 57 d5 18 00 <75> 13 48 63 44 24 20 48 0f a3 05 5d c7 d1 12 0f 83 62 1e 00 00 49 RSP: 0018:ffffc90000007be0 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000003 RCX: ffffffff9415dd58 RDX: 0000000000000008 RSI: ffff8880299ee918 RDI: ffff8880299edd00 RBP: 0000000000000000 R08: ffffffff81b3a166 R09: 0000000000080000 R10: 0000000000000000 R11: ffff8880b86281d8 R12: 0000000000000002 R13: ffff8880299ee918 R14: ffff8880299edd00 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff888124f54000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb02ae6bff8 CR3: 000000007b77c000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock_irq+0x3d/0x50 kernel/locking/spinlock.c:174 __run_hrtimer kernel/time/hrtimer.c:2036 [inline] __hrtimer_run_queues+0x466/0xa10 kernel/time/hrtimer.c:2096 hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2215 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline] __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline] RIP: 0010:vprintk_emit+0x45d/0x560 kernel/printk/printk.c:2478 Code: 0f 84 44 ff ff ff e8 f2 69 21 00 fb eb 44 e8 ea 69 21 00 e8 85 2d 2b 0a 4d 85 f6 74 94 e8 db 69 21 00 fb 48 c7 c7 a0 bf b4 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 fb 1b RSP: 0018:ffffc90005eaf3a0 EFLAGS: 00000293 RAX: ffffffff81a597a5 RBX: ffffffff81a5961f RCX: ffff8880299edd00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8eb4bfa0 RBP: ffffc90005eaf450 R08: ffffffff90578f37 R09: 1ffffffff20af1e6 R10: dffffc0000000000 R11: fffffbfff20af1e7 R12: 0000000000000000 R13: 000000000000002d R14: 0000000000000200 R15: 1ffff92000bd5e78 dev_vprintk_emit+0x338/0x400 drivers/base/core.c:4996 dev_printk_emit+0xee/0x140 drivers/base/core.c:5007 __netdev_printk+0x3e1/0x480 net/core/dev.c:13085 netdev_warn+0x11e/0x180 net/core/dev.c:13138 ieee802154_subif_start_xmit+0x136/0x190 net/mac802154/tx.c:232 __netdev_start_xmit include/linux/netdevice.h:5424 [inline] netdev_start_xmit include/linux/netdevice.h:5433 [inline] xmit_one net/core/dev.c:3892 [inline] dev_hard_start_xmit+0x2cd/0x830 net/core/dev.c:3908 sch_direct_xmit+0x257/0x4c0 net/sched/sch_generic.c:372 __dev_xmit_skb net/core/dev.c:4217 [inline] __dev_queue_xmit+0x177f/0x3820 net/core/dev.c:4839 dev_queue_xmit include/linux/netdevice.h:3451 [inline] tx+0x6b/0x190 drivers/block/aoe/aoenet.c:62 kthread+0x1ed/0x420 drivers/block/aoe/aoecmd.c:1241 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245