[LTP] [PATCH] commands/sysctl: Add new regression test for invalid sched_time_avg

[Xiao Yang]

On 2018/03/15 1:01, Cyril Hrubis wrote:
> Hi!
>>> What is this sleep good for? Do we wait here for the kernel to crash?
>> On my RHEL6, restoring the original value immediately after setting an
>> invalid value always didn't
>> trigger a hang in time, so we just wait a moment for kernel to hang.
Hi,
> Shouldn't the kernel crash just by setting the avg_ms to 0 or do I
> misunderstand the kernel commit changelog?
Yes,  if the value which is set to 0 is picked up  by the scheduller, 
the kernel shouldn't crash.
> Or is the offending code that crashes the kernel invoked asynchronously
> so that the value is picked up later by the scheduller? If so I would
> prefer removing the sleep anyways since the test will fail if we happen
> to be able to write 0 to the file anyways which is IMHO enough to inform
> the user about the present bug.
It seems reasonable, and i will remove the sleep.

Thanks,
Xiao Yang
> Other than that the test looks fine.
>