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Date:   Thu, 26 Sep 2019 00:16:03 +0000 (UTC)
From:   Christopher Lameter <cl@linux.com>
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To:     Vlastimil Babka <vbabka@suse.cz>
cc:     Andrew Morton <akpm@linux-foundation.org>,
        David Sterba <dsterba@suse.cz>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Ming Lei <ming.lei@redhat.com>,
        Dave Chinner <david@fromorbit.com>,
        Matthew Wilcox <willy@infradead.org>,
        "Darrick J . Wong" <darrick.wong@oracle.com>,
        Christoph Hellwig <hch@lst.de>, linux-xfs@vger.kernel.org,
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        linux-btrfs@vger.kernel.org, Roman Gushchin <guro@fb.com>,
        Johannes Weiner <hannes@cmpxchg.org>
Subject: Re: [PATCH v2 2/2] mm, sl[aou]b: guarantee natural alignment for
 kmalloc(power-of-two)
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On Wed, 25 Sep 2019, Vlastimil Babka wrote:

> Most of the new code is for SLOB, which has no debugging and yet
> misaligns. For SLUB and SLAB, it's just passing alignment argument to
> kmem_cache_create() for kmalloc caches, which means just extra few
> instructions during boot, and no extra code during kmalloc/kfree itself.

SLOB follows the standards for alignments in slab allocators and will
correctly align if you ask the allocator for a properly aligned object.