rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=12493, q=372) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294964532-4294954030), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.1 R running task 23424 10158 8039 0x00004000 Call Trace: sched_show_task+0x3bd/0x490 kernel/sched/core.c:5286 print_other_cpu_stall kernel/rcu/tree_stall.h:410 [inline] check_cpu_stall kernel/rcu/tree_stall.h:536 [inline] rcu_pending kernel/rcu/tree.c:2625 [inline] rcu_sched_clock_irq+0x1607/0x1740 kernel/rcu/tree.c:2161 update_process_times+0x134/0x190 kernel/time/timer.c:1639 tick_sched_handle kernel/time/tick-sched.c:167 [inline] tick_sched_timer+0x257/0x410 kernel/time/tick-sched.c:1298 __run_hrtimer kernel/time/hrtimer.c:1389 [inline] __hrtimer_run_queues+0x471/0x8b0 kernel/time/hrtimer.c:1451 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1509 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline] smp_apic_timer_interrupt+0xee/0x260 arch/x86/kernel/apic/apic.c:1066 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:806 RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:67 Code: 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 aa <4c> 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01 RSP: 0018:ffff888090b9f4e8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: ffff8880922cb37f RCX: 0000000000000000 RDX: 0000000000000020 RSI: 0000000000000000 RDI: ffffed1012459670 RBP: ffff888090b9f748 R08: ffff88805612a8c0 R09: ffffed1012459650 R10: 1ffff1100ac2551d R11: 0000000000000000 R12: ffffed1012459670 R13: 0000000000000100 R14: ffff8880922cb380 R15: ffff8880922cb37f kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:497 slab_post_alloc_hook mm/slab.h:437 [inline] slab_alloc mm/slab.c:3326 [inline] __do_kmalloc mm/slab.c:3658 [inline] __kmalloc+0x213/0x310 mm/slab.c:3669 kmalloc_array+0x32/0x60 include/linux/slab.h:670 kcalloc include/linux/slab.h:681 [inline] iter_file_splice_write+0x220/0xf40 fs/splice.c:690 do_splice_from fs/splice.c:848 [inline] direct_splice_actor+0xf7/0x130 fs/splice.c:1020 splice_direct_to_actor+0x4c6/0xb40 fs/splice.c:975 do_splice_direct+0x279/0x3d0 fs/splice.c:1063 do_sendfile+0x8a3/0x1110 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+0x1bc/0x220 fs/read_write.c:1511 do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4592c9 Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2a51bc1c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000004592c9 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 00008000fffffffe R11: 0000000000000246 R12: 00007f2a51bc26d4 R13: 00000000004c689d R14: 00000000004db828 R15: 00000000ffffffff rcu: rcu_preempt kthread starved for 10502 jiffies! g12493 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 26176 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x658/0x9e0 kernel/sched/core.c:3445 schedule+0x131/0x1d0 kernel/sched/core.c:3509 schedule_timeout+0x19d/0x2b0 kernel/time/timer.c:1807 rcu_gp_fqs_loop kernel/rcu/tree.c:1589 [inline] rcu_gp_kthread+0xfd8/0x1880 kernel/rcu/tree.c:1746 kthread+0x325/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352