rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=177433, q=472) rcu: All QSes seen, last rcu_preempt kthread activity 10501 (4295047308-4295036807), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.3 R running task 26224 14658 11066 0x8000000a Call Trace: sched_show_task.cold+0x332/0x396 kernel/sched/core.c:5337 print_other_cpu_stall kernel/rcu/tree.c:1430 [inline] check_cpu_stall kernel/rcu/tree.c:1557 [inline] __rcu_pending kernel/rcu/tree.c:3293 [inline] rcu_pending kernel/rcu/tree.c:3336 [inline] rcu_check_callbacks.cold+0xb37/0xe19 kernel/rcu/tree.c:2682 update_process_times+0x2a/0x70 kernel/time/timer.c:1650 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168 tick_sched_timer+0xfc/0x290 kernel/time/tick-sched.c:1278 __run_hrtimer kernel/time/hrtimer.c:1401 [inline] __hrtimer_run_queues+0x3f6/0xe60 kernel/time/hrtimer.c:1463 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1521 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline] smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:435 [inline] RIP: 0010:__pv_queued_spin_lock_slowpath+0x3a6/0xae0 kernel/locking/qspinlock.c:474 Code: eb c6 45 01 01 41 bc 00 80 00 00 48 c1 e9 03 83 e3 07 41 be 01 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8d 2c 01 eb 0c f3 90 <41> 83 ec 01 0f 84 38 04 00 00 41 0f b6 45 00 38 d8 7f 08 84 c0 0f RSP: 0018:ffff88806d7ff380 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000003 RBX: 0000000000000000 RCX: 1ffffffff1479b6c RDX: 0000000000000001 RSI: ffffffff81677d85 RDI: 0000000000000286 RBP: ffffffff8a3cdb60 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000004f02 R13: fffffbfff1479b6c R14: 0000000000000001 R15: ffff8880ba02bd80 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:679 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:53 [inline] queued_spin_lock include/asm-generic/qspinlock.h:88 [inline] do_raw_spin_lock+0x189/0x220 kernel/locking/spinlock_debug.c:113 spin_lock include/linux/spinlock.h:329 [inline] proc_keys_start+0x4d/0x450 security/keys/proc.c:123 seq_read+0x2a0/0x1160 fs/seq_file.c:224 proc_reg_read+0x1bd/0x2d0 fs/proc/inode.c:231 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x471/0x630 fs/read_write.c:925 vfs_readv+0xe5/0x150 fs/read_write.c:987 kernel_readv fs/splice.c:362 [inline] default_file_splice_read+0x457/0xa00 fs/splice.c:417 do_splice_to+0x10e/0x160 fs/splice.c:881 splice_direct_to_actor+0x2b9/0x8d0 fs/splice.c:959 do_splice_direct+0x1a7/0x270 fs/splice.c:1068 do_sendfile+0x550/0xc30 fs/read_write.c:1447 __do_sys_sendfile64 fs/read_write.c:1508 [inline] __se_sys_sendfile64+0x147/0x160 fs/read_write.c:1494 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465b09 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb94111f188 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465b09 RDX: 0000000000000000 RSI: 0000000000000007 RDI: 0000000000000004 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000020000000005 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fff084adcdf R14: 00007fb94111f300 R15: 0000000000022000 rcu: rcu_preempt kthread starved for 10543 jiffies! g177433 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29208 10 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 schedule_timeout+0x4cf/0xfe0 kernel/time/timer.c:1818 rcu_gp_kthread+0xdad/0x21c0 kernel/rcu/tree.c:2202 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415