INFO: rcu detected stall in sendfile64

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
linux-5.15	INFO: rcu detected stall in sendfile64	1				1	69d	69d	0/3	upstream: reported on 2025/11/07 23:07
linux-4.14	INFO: rcu detected stall in sendfile64 (2)	1				3	1989d	2144d	0/1	auto-closed as invalid on 2020/12/03 20:18

net_ratelimit: 25 callbacks suppressed protocol 88fb is buggy, dev hsr_slave_0 protocol 88fb is buggy, dev hsr_slave_1 protocol 88fb is buggy, dev hsr_slave_0 protocol 88fb is buggy, dev hsr_slave_1 INFO: rcu_sched self-detected stall on CPU 0-...: (10499 ticks this GP) idle=a6e/140000000000001/0 softirq=223324/223327 fqs=0 (t=10500 jiffies g=49836 c=49835 q=3) rcu_sched kthread starved for 10500 jiffies! g49836 c49835 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0 rcu_sched R running task 29776 9 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x43e/0xe10 kernel/time/timer.c:1744 rcu_gp_kthread+0xbf4/0x1ec0 kernel/rcu/tree.c:2255 kthread+0x31c/0x430 kernel/kthread.c:232 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402 NMI backtrace for cpu 0 CPU: 0 PID: 9032 Comm: syz-executor.3 Not tainted 4.14.111 #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x138/0x19c lib/dump_stack.c:53 nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x141/0x189 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:158 [inline] rcu_dump_cpu_stacks+0x186/0x1d2 kernel/rcu/tree.c:1396 print_cpu_stall kernel/rcu/tree.c:1542 [inline] check_cpu_stall kernel/rcu/tree.c:1610 [inline] __rcu_pending kernel/rcu/tree.c:3390 [inline] rcu_pending kernel/rcu/tree.c:3452 [inline] rcu_check_callbacks.cold+0x43d/0xd0a kernel/rcu/tree.c:2792 update_process_times+0x31/0x70 kernel/time/timer.c:1588 tick_sched_handle+0x85/0x160 kernel/time/tick-sched.c:161 tick_sched_timer+0x43/0x130 kernel/time/tick-sched.c:1219 __run_hrtimer kernel/time/hrtimer.c:1220 [inline] __hrtimer_run_queues+0x273/0xbd0 kernel/time/hrtimer.c:1284 hrtimer_interrupt+0x1d8/0x5d0 kernel/time/hrtimer.c:1318 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] smp_apic_timer_interrupt+0x12c/0x600 arch/x86/kernel/apic/apic.c:1062 apic_timer_interrupt+0x8e/0xa0 arch/x86/entry/entry_64.S:787 </IRQ> RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:778 [inline] RIP: 0010:lock_acquire+0x1ea/0x430 kernel/locking/lockdep.c:3997 RSP: 0018:ffff88802d5ff8d8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10 RAX: 1ffffffff0ee2965 RBX: ffff88807f9022c0 RCX: 0000000037b75585 RDX: dffffc0000000000 RSI: ffff88807f902b68 RDI: 0000000000000282 RBP: ffff88802d5ff920 R08: 0000000000003f71 R09: ffffffff88c97f48 R10: ffff88807f902b68 R11: ffff88807f9022c0 R12: ffffffff877efe60 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 fs_reclaim_acquire.part.0+0x24/0x30 mm/page_alloc.c:3551 fs_reclaim_acquire+0x14/0x20 mm/page_alloc.c:3552 slab_pre_alloc_hook mm/slab.h:416 [inline] slab_alloc mm/slab.c:3376 [inline] __do_kmalloc mm/slab.c:3718 [inline] __kmalloc+0x52/0x7a0 mm/slab.c:3729 kmalloc_array include/linux/slab.h:607 [inline] kcalloc include/linux/slab.h:618 [inline] iter_file_splice_write+0x141/0xae0 fs/splice.c:692 do_splice_from fs/splice.c:851 [inline] direct_splice_actor+0x126/0x1a0 fs/splice.c:1018 splice_direct_to_actor+0x2a1/0x7b0 fs/splice.c:973 do_splice_direct+0x18d/0x230 fs/splice.c:1061 do_sendfile+0x4db/0xbd0 fs/read_write.c:1440 SYSC_sendfile64 fs/read_write.c:1501 [inline] SyS_sendfile64+0x102/0x110 fs/read_write.c:1487 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4582f9 RSP: 002b:00007f9d93eb9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000004582f9 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000004 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 00008000fffffffe R11: 0000000000000246 R12: 00007f9d93eba6d4 R13: 00000000004c5267 R14: 00000000004d93a8 R15: 00000000ffffffff INFO: rcu_preempt detected stalls on CPUs/tasks: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7215 (detected by 0, t=10545 jiffies, g=86519, c=86518, q=87) kworker/u4:5 R running task 25312 7215 2 0x80000000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383 preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:3610 retint_kernel+0x1b/0x2d RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:778 [inline] RIP: 0010:lock_acquire+0x1ea/0x430 kernel/locking/lockdep.c:3997 RSP: 0018:ffff88806ecd7c90 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10 RAX: 1ffffffff0ee2965 RBX: ffff88806ecce640 RCX: 000000002e890d4b RDX: dffffc0000000000 RSI: ffff88806eccef10 RDI: 0000000000000282 RBP: ffff88806ecd7cd8 R08: 0000000000000000 R09: ffff88806eccef30 R10: ffff88806eccef10 R11: ffff88806ecce640 R12: ffffffff8778ed60 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000002 rcu_lock_acquire include/linux/rcupdate.h:244 [inline] rcu_read_lock include/linux/rcupdate.h:631 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:416 [inline] batadv_nc_worker+0x107/0x6d0 net/batman-adv/network-coding.c:726 process_one_work+0x868/0x1610 kernel/workqueue.c:2114 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248 kthread+0x31c/0x430 kernel/kthread.c:232 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402 kworker/u4:5 R running task 25312 7215 2 0x80000000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383 preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:3610 retint_kernel+0x1b/0x2d RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:778 [inline] RIP: 0010:lock_acquire+0x1ea/0x430 kernel/locking/lockdep.c:3997 RSP: 0018:ffff88806ecd7c90 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10 RAX: 1ffffffff0ee2965 RBX: ffff88806ecce640 RCX: 000000002e890d4b RDX: dffffc0000000000 RSI: ffff88806eccef10 RDI: 0000000000000282 RBP: ffff88806ecd7cd8 R08: 0000000000000000 R09: ffff88806eccef30 R10: ffff88806eccef10 R11: ffff88806ecce640 R12: ffffffff8778ed60 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000002 rcu_lock_acquire include/linux/rcupdate.h:244 [inline] rcu_read_lock include/linux/rcupdate.h:631 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:416 [inline] batadv_nc_worker+0x107/0x6d0 net/batman-adv/network-coding.c:726 process_one_work+0x868/0x1610 kernel/workqueue.c:2114 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248 kthread+0x31c/0x430 kernel/kthread.c:232 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402 rcu_preempt kthread starved for 10545 jiffies! g86519 c86518 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=1 rcu_preempt R running task 29776 8 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x43e/0xe10 kernel/time/timer.c:1744 rcu_gp_kthread+0xbf4/0x1ec0 kernel/rcu/tree.c:2255 kthread+0x31c/0x430 kernel/kthread.c:232 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402 sched: RT throttling activated