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Date:   Tue, 26 Jul 2022 16:30:55 +0200
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Subject: Re: [PATCHv7 02/14] mm: Add support for unaccepted memory
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To:     Borislav Petkov <bp@alien8.de>
Cc:     Dave Hansen <dave.hansen@intel.com>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Sean Christopherson <seanjc@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Ard Biesheuvel <ardb@kernel.org>,
        Andi Kleen <ak@linux.intel.com>,
        Kuppuswamy Sathyanarayanan 
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From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
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On 25.07.22 14:53, Borislav Petkov wrote:
> On Mon, Jul 25, 2022 at 02:38:57PM +0200, David Hildenbrand wrote:
>> The less core-MM code to handle unaccepted memory the better. Meaning,
>> that any kind of additional pre-acceptance (in addition to what we have
>> here) needs good justification.
> 
> I actually mean to have a user interface to have the core code
> pre-accept. I.e., interface to what will be already there anyway.
>

Ah, got it. The "issue" with ordinary prefaulting in user space is that
you'll also end up zeroing the memory. But yeah, it should just accept a
bunch of memory.

> Or is that frowned upon too?

I was assuming you'd want some additional interface that only accept
memory without actually temporarily allocating it.

-- 
Thanks,

David / dhildenb