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From:   Len Brown <lenb@kernel.org>
Date:   Thu, 27 May 2021 09:59:00 -0400
Message-ID: <CAJvTdK=Z5LMU9ehFH2NVFCP7LLEvaTtywfuZHdwRb9-7hvE8KA@mail.gmail.com>
Subject: Re: second, sync-alloc syscall
To:     Borislav Petkov <bp@alien8.de>
Cc:     "Chang S. Bae" <chang.seok.bae@intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@kernel.org>, X86 ML <x86@kernel.org>,
        "Brown, Len" <len.brown@intel.com>,
        Dave Hansen <dave.hansen@intel.com>,
        "Liu, Jing2" <jing2.liu@intel.com>,
        "Ravi V. Shankar" <ravi.v.shankar@intel.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Thu, May 27, 2021 at 7:14 AM Borislav Petkov <bp@alien8.de> wrote:

> So if this second syscall doesn't sound really great, I'd say we stick
> to the #NM-based allocation and keep this one in the bag for now and
> take it out only if it turns out that it makes sense as a use case.

I agree.  Simple to add if later, if something requires it --
though given it's modest incremental value, currently hard to justify.

> As tglx said: it is easy to add stuff later. It is a lot harder - even
> impossible - to remove already present machinery.

Indeed.

thanks!
Len Brown, Intel Open Source Technology Center