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Date:   Wed, 15 Apr 2020 00:48:13 +1000
From:   Nicholas Piggin <npiggin@gmail.com>
Subject: Re: [PATCH v2 4/4] mm/vmalloc: Hugepage vmalloc mappings
To:     Christoph Hellwig <hch@infradead.org>
Cc:     Borislav Petkov <bp@alien8.de>,
        Catalin Marinas <catalin.marinas@arm.com>,
        "H. Peter Anvin" <hpa@zytor.com>, linux-arch@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org,
        Ingo Molnar <mingo@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Will Deacon <will@kernel.org>, x86@kernel.org
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Excerpts from Christoph Hellwig's message of April 14, 2020 11:02 pm:
> On Tue, Apr 14, 2020 at 10:13:44PM +1000, Nicholas Piggin wrote:
>> Which case? Usually the answer would be because you don't want to use
>> contiguous physical memory and/or you don't want to use the linear=20
>> mapping.
>=20
> But with huge pages you do by definition already use large contiguous
> areas.  So you want allocations larger than "small" huge pages but not
> using gigantic pages using vmalloc?

Yes.

Thanks,
Nick