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Date:   Tue, 24 Sep 2019 20:55:02 +0000 (UTC)
From:   cl@linux.com
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To:     Matthew Wilcox <willy@infradead.org>
cc:     "Darrick J. Wong" <darrick.wong@oracle.com>, dsterba@suse.cz,
        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>,
        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)
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n Tue, 24 Sep 2019, Matthew Wilcox wrote:

> > There was a public discussion about this issue and from what I can tell
> > the outcome was that the allocator already provides what you want. Which
> > was a mechanism to misalign objects and detect these issues. This
> > mechanism has been in use for over a decade.
>
> You missed the important part, which was *ENABLED BY DEFAULT*.  People
> who are enabling a debugging option to debug their issues, should not
> have to first debug all the other issues that enabling that debugging
> option uncovers!

Why would you have to debug all other issues? You could put your patch on
top of the latest stable or distro kernel for testing.

And I thought the rc phase was there for everyone to work on the bugs of
each other?