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Date:   Sat, 29 Aug 2020 11:24:06 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Christoph Hellwig <hch@lst.de>, Al Viro <viro@zeniv.linux.org.uk>,
        Michael Ellerman <mpe@ellerman.id.au>,
        the arch/x86 maintainers <x86@kernel.org>,
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Subject: Re: [PATCH 05/10] lkdtm: disable set_fs-based tests for
 !CONFIG_SET_FS
Message-ID: <20200829092406.GB8833@lst.de>
References: <20200827150030.282762-1-hch@lst.de> <20200827150030.282762-6-hch@lst.de> <CAHk-=wipbWD66sU7etETXwDW5NRsU2vnbDpXXQ5i94hiTcawyw@mail.gmail.com>
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On Thu, Aug 27, 2020 at 11:06:28AM -0700, Linus Torvalds wrote:
> On Thu, Aug 27, 2020 at 8:00 AM Christoph Hellwig <hch@lst.de> wrote:
> >
> > Once we can't manipulate the address limit, we also can't test what
> > happens when the manipulation is abused.
> 
> Just remove these tests entirely.
> 
> Once set_fs() doesn't exist on x86, the tests no longer make any sense
> what-so-ever, because test coverage will be basically zero.
> 
> So don't make the code uglier just to maintain a fiction that
> something is tested when it isn't really.

Sure fine with me unless Kees screams.