makedumpfile-1.5.9: Introduce parallel compression processing.

[Atsushi Kumagai]

Hello Louis,

>>>> o Support new kernels
>>>>  - The supported kernel is updated to 4.1 in this version.
>>>>    At first I'm going to extend the supported version to 4.2, but
>>>>    I found an issue that makedumpfile seems to exclude necessary pages
>>>>    by mistake on linux 4.2. When crash-7.1.3 reads that filtered dump file,
>>>>    the following message is shown.
>>>>
>>>>       crash: page excluded: kernel virtual address: f3fe0000  type: "fill_task_struct"
>>>>
>>>>    This will be fixed in the next version.
>>>
>>> Have you fixed the 4.2 kernel issue already or you intend to work on it in the
>>> future ?
>>
>> I haven't done anything yet, I was going to work from now.
>>
>>> Both Debian and Ubuntu run 4.2 kernel so if waiting for a fix is acceptable I
>>> would rather bring in a 1.5.9 + patch version.
>>
>> So it will be helpful if you can do it.
>>
>>
>> Thanks,
>> Atsushi Kumagai
>>
>
>That is perfect.  Just let me know once you have identified a fix and I will
>include it in the new package.

I confirmed that there is no problem in makedumpfile, so you don't need to
update your makedumpfile packages.

That was a crash side issue and the problem is still under discussion.
The warning I reported first is going to be solved in the next crash version,
but "struct" and "task" commands with task_struct (or some corresponding fields)
can fail if a dumpfile of linux 4.2 is filtered.

You should see this thread for more details:

  https://www.redhat.com/archives/crash-utility/2015-November/msg00021.html


Thanks,
Atsushi Kumagai