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Date:   Tue, 24 Sep 2019 20:52:52 +0000 (UTC)
From:   cl@linux.com
To:     David Sterba <dsterba@suse.cz>
cc:     Vlastimil Babka <vbabka@suse.cz>,
        Andrew Morton <akpm@linux-foundation.org>, 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,
        linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org,
        James Bottomley <James.Bottomley@HansenPartnership.com>,
        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)
In-Reply-To: <20190923171710.GN2751@twin.jikos.cz>
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On Mon, 23 Sep 2019, David Sterba wrote:

> As a user of the allocator interface in filesystem, I'd like to see a
> more generic way to address the alignment guarantees so we don't have to
> apply workarounds like 3acd48507dc43eeeb each time we find that we
> missed something. (Where 'missed' might be another sort of weird memory
> corruption hard to trigger.)

The alignment guarantees are clearly documented and objects are misaligned
in debugging kernels.

Looking at 3acd48507dc43eeeb:Looks like no one tested that patch with a
debug kernel or full debugging on until it hit mainline. Not good.

The consequence for the lack of proper testing is to make the production
kernel contain the debug measures?