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Message-ID: <b55720804de8e56febf48c7c3c11b578d06a8c9f.camel@sipsolutions.net>
Subject: Re: [RFC PATCH] UML: add support for KASAN under x86_64
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Patricia Alfonso <trishalfonso@google.com>
Cc:     richard@nod.at, jdike@addtoit.com,
        Brendan Higgins <brendanhiggins@google.com>,
        linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com,
        linux-um@lists.infradead.org, David Gow <davidgow@google.com>,
        aryabinin@virtuozzo.com, dvyukov@google.com,
        anton.ivanov@cambridgegreys.com
Date:   Thu, 16 Jan 2020 09:03:35 +0100
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On Thu, 2020-01-16 at 08:57 +0100, Johannes Berg wrote:
> 
> And if I remember from looking at KASAN, some of the constructors there
> depended on initializing after the KASAN data structures were set up (or
> at least allocated)? It may be that you solved that by allocating the
> shadow so very early though.

Actually, no ... it's still after main(), and the constructors run
before.

So I _think_ with the CONFIG_CONSTRUCTORS revert, this will no longer
work (but happy to be proven wrong!), if so then I guess we do have to
find a way to initialize the KASAN things from another (somehow
earlier?) constructor ...

Or find a way to fix CONFIG_CONSTRUCTORS and not revert, but I looked at
it quite a bit and didn't.

johannes