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Subject: Re: [RFC 0/3] kunit: add support to use modules
From:   Vitor Massaru Iha <vitor@massaru.org>
To:     Kees Cook <keescook@chromium.org>, David Gow <davidgow@google.com>
Cc:     KUnit Development <kunit-dev@googlegroups.com>,
        "open list:KERNEL SELFTEST FRAMEWORK" 
        <linux-kselftest@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Brendan Higgins <brendanhiggins@google.com>,
        Shuah Khan <skhan@linuxfoundation.org>,
        linux-kernel-mentees@lists.linuxfoundation.org
Date:   Thu, 16 Jul 2020 13:32:01 -0300
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         <CABVgOSkBAiMSMzCx62_CRo_0e2SGdvRWZ0dSC4t628YJBw-3Aw@mail.gmail.com>
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On Wed, 2020-07-15 at 19:41 -0700, Kees Cook wrote:
> On Wed, Jul 15, 2020 at 11:47:11AM +0800, David Gow wrote:
> > - The inheriting of the mm stuff still means that
> > copy_{from,to}_user() will only work if loaded as a module. This
> > really needs to be documented. (Ideally, we'd find a way of having
> > this work even for built-in tests, but I don't have any real ideas
> > as
> > to how that could be done).
> 
> I'd like to better understand this ... are there conditions where
> vm_mmap() doesn't work? I thought this would either use current()
> (e.g.
> how LKDTM uses it when getting triggered from debugfs), or use
> init_mm.
> 
> I'd really like to see the mm patch more well described/justified.
> 

Sure, I'll describe the patch better.

Thanks for the review.