Description of problem:
Once we echo 0 > /proc/pid/sched, the wait_start will be cleared. And if the task is excatly waiting in run queue, the wait_max will be much greater than the actual value, closing to the boot time.

Version-Release number of selected component (if applicable):
devel-5.10

How reproducible:
echo 0 > /proc/[pid]/sched

Steps to Reproduce:
1.echo 0 > /proc/[pid]/sched
2.cat /proc/[pid]/sched | grep wait_max

Actual results:
54768574.070401

Expected results:
29.999171