rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=18845, q=82) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294978485-4294967983), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.5 R running task 26328 10895 9416 0x00004000 Call Trace: sched_show_task kernel/sched/core.c:5954 [inline] sched_show_task.cold+0x2ee/0x35d kernel/sched/core.c:5929 print_other_cpu_stall kernel/rcu/tree_stall.h:410 [inline] check_cpu_stall kernel/rcu/tree_stall.h:538 [inline] rcu_pending kernel/rcu/tree.c:2827 [inline] rcu_sched_clock_irq.cold+0xaf4/0xc0d kernel/rcu/tree.c:2271 update_process_times+0x2d/0x70 kernel/time/timer.c:1726 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1310 __run_hrtimer kernel/time/hrtimer.c:1517 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1579 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1641 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline] smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1135 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:__sanitizer_cov_trace_pc+0x1/0x50 kernel/kcov.c:180 Code: cc cc cc cc cc cc cc cc cc 65 48 8b 04 25 c0 1e 02 00 48 8b 80 98 13 00 00 c3 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 55 <48> 89 e5 65 48 8b 04 25 c0 1e 02 00 65 8b 15 e4 28 8d 7e 81 e2 00 RSP: 0018:ffffc90001557900 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000002 RBX: 0000000000000001 RCX: ffffffff81cb01f5 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffffc90001557938 R08: ffff88805377e600 R09: fffff94000153521 R10: fffff94000153520 R11: ffffea0000a9a907 R12: ffffea0000a9a900 R13: ffffea0000a9a908 R14: 0000000000000000 R15: dead000000000100 pipe_buf_confirm include/linux/pipe_fs_i.h:196 [inline] iter_file_splice_write+0x5cf/0xc10 fs/splice.c:746 do_splice_from fs/splice.c:863 [inline] direct_splice_actor+0x123/0x190 fs/splice.c:1037 splice_direct_to_actor+0x3b4/0xa30 fs/splice.c:992 do_splice_direct+0x1da/0x2a0 fs/splice.c:1080 do_sendfile+0x597/0xd00 fs/read_write.c:1464 __do_sys_sendfile64 fs/read_write.c:1525 [inline] __se_sys_sendfile64 fs/read_write.c:1511 [inline] __x64_sys_sendfile64+0x1dd/0x220 fs/read_write.c:1511 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45af49 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f0ef2550c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045af49 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000007 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 00008000fffffffe R11: 0000000000000246 R12: 00007f0ef25516d4 R13: 00000000004c9b06 R14: 00000000004e2ae0 R15: 00000000ffffffff rcu: rcu_preempt kthread starved for 10502 jiffies! g18845 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29264 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4081 schedule+0xdc/0x2b0 kernel/sched/core.c:4155 schedule_timeout+0x486/0xc50 kernel/time/timer.c:1895 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline] rcu_gp_kthread+0x9b2/0x18d0 kernel/rcu/tree.c:1821 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352