Re: [PATCH 0 of 3] mmu notifier v18 for -mm

Avi Kivity
2008-07-02T04:58:55Z

Andrew Morton wrote:
> On Thu, 26 Jun 2008 02:26:56 +0200 Andrea Arcangeli <andrea@qumranet.com> wrote:
>
>
>> Hello,
>>
>> Christoph suggested me to repost v18 for merging in -mm, to give it more
>> exposure before the .27 merge window opens. There's no code change compared to
>> the previous v18 submission (the only change is the correction in the comment
>> in the mm_take_all_locks patch rightfully pointed out by Linus).
>>
>> Full patchset including other XPMEM support patches can be found here:
>>
>> http://www.kernel.org/pub/linux/kernel/people/andrea/patches/v2.6/2.6.26-rc7/mmu-notifier-v18
>>
>> Only the three patches of the patchset I'm submitting here by email are ready
>> for merging, the rest you can find in the website is not ready for merging yet
>> for various performance degradations, lots of the XPMEM patches needs to be
>> elaborated to avoid any slowdown for the non-XPMEM case, but I keep
>> maintaining them to make life easier to XPMEM current development and later we
>> can keep work on them to make them suitable for inclusion to avoid any
>> performance degradation risk.
>>
>
> I'm a bit concerned about merging the first three patches when there
> are eleven more patches of which some, afacit, are required to make
> these three actually useful. Committing these three would be signing a
> blank cheque.
>
>

The first three are useful for kvm, gru, and likely drm and rdma nics.

It is only xpmem which requires the other eleven patches.

> Because if we hit strong objections with the later patches we end up in a
> cant-go-forward, cant-go-backward situation.
>
>

No, we end up in a some-people-are-happy,
some-have-to-redo-their-homework situation.

--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.