RE: [EXTERNAL] Re: [PATCH 1/2] x86/Kconfig: Allow CONFIG_X86_MPPARSE disable for OF platforms

[Saurabh Singh Sengar <ssengar@microsoft.com>]

> -----Original Message-----
> From: Dave Hansen <dave.hansen@intel.com>
> Sent: Friday, June 2, 2023 7:54 PM
> To: Saurabh Singh Sengar <ssengar@microsoft.com>; Saurabh Sengar
> <ssengar@linux.microsoft.com>; tglx@linutronix.de; mingo@redhat.com;
> bp@alien8.de; dave.hansen@linux.intel.com; x86@kernel.org;
> hpa@zytor.com; KY Srinivasan <kys@microsoft.com>; Haiyang Zhang
> <haiyangz@microsoft.com>; wei.liu@kernel.org; Dexuan Cui
> <decui@microsoft.com>; Michael Kelley (LINUX) <mikelley@microsoft.com>;
> linux-kernel@vger.kernel.org; linux-hyperv@vger.kernel.org
> Subject: [EXTERNAL] Re: [PATCH 1/2] x86/Kconfig: Allow
> CONFIG_X86_MPPARSE disable for OF platforms
> 
> On 6/2/23 05:22, Saurabh Singh Sengar wrote:
> > Furthermore, I would like to learn about the rationale behind
> > disallowing the disablement of CONFIG_X86_MPPARSE when MP tables are
> > not in use. Considering that we compile out the features we don't
> > support, wouldn't it be acceptable to allow users to customize their
> > configurations in this manner? Allowing the disablement of
> > CONFIG_X86_MPPARSE would provide greater flexibility and efficiency for
> those who do not utilize MP tables.
> 
> If someone sent a patch, I'd certainly look and figure out what "flexibility" and
> "efficiency" it would provide.  But, honestly, it would just just be noise if it
> doesn't solve an _actual_ problem.
> 
> Would anyone care or notice the "flexibility" and "efficiency" it would
> provide?

After the new approach we have opted, I agree it's not blocking us from any functional
problem. Although one of the things we are trying to achieve is the minimal kernel
where we want to remove all the unnecessary options. Our system is not dependent
MPPARSE and we just don't want this code in our minimal kernel, and this config
option is preventing us from removing it.

Also, in past kernel has provided this flexibility for other options, which made me think
it is fine do it for OF as well.
https://lkml.indiana.edu/hypermail/linux/kernel/1210.3/01987.html

Happy to know your opinion and learn.