Re: [Patch] Call sched_destroy_domain before cpupool_rm_domain.

[Juergen Gross <juergen.gross@ts.fujitsu.com>]

On 07.11.2013 08:39, Jan Beulich wrote:
>>>> On 05.11.13 at 06:59, Juergen Gross <juergen.gross@ts.fujitsu.com> wrote:
>> On 04.11.2013 16:22, Nate Studer wrote:
>>> On 11/4/2013 4:58 AM, Juergen Gross wrote:
>>>> All other schedulers will just call xfree() for the domain specific data (and
>>>> may be update some statistic data, which is not critical).
>>>
>>> The credit and credit2 schedulers do a bit more than that in their free_domdata
>>> functions.
>>
>> Sorry, got not enough sleep on the weekend ;-)
>>
>> I checked only 4.1 and 4.2 trees. There only xfree of the domain data is
>> done.
>>
>>>
>>> The credit scheduler frees the node_affinity_cpumask contained in the domain
>>> data and the credit2 scheduler deletes a list element contained in the domain
>>> data.  Since with this bug they are accessing structures that do not belong to
>>> them, bad things happen.
>>
>> So the patch would be subject to a 4.3 backport, I think.
>
> Hmm, I'm slightly confused: credit2's free_domdata has always been
> doing more than just xfree() afaict, and hence backporting is either
> necessary uniformly or (taking into account that it was made clear
> that arinc doesn't work with CPU pools anyway so far) not at all.
>
> Please clarify.

Okay, I assumed only "production ready" features are to be taken into account
for a backport. And credit2 is clearly not in this state, or am I wrong?

A 4.3 backport should be considered in any case, as sedf and credit schedulers
behave differently in free_domdata, and both are "production ready". If you
want to be safe for credit2 and/or arinc653 as well, backports to 4.2 and 4.1
will be required.

In any case a backport isn't very complex. :-)


Juergen

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Juergen Gross                 Principal Developer Operating Systems
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