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Date:   Tue, 14 Apr 2020 06:02:03 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Nicholas Piggin <npiggin@gmail.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        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
Subject: Re: [PATCH v2 4/4] mm/vmalloc: Hugepage vmalloc mappings
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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 
> mapping.

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?