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Date:   Wed, 6 Dec 2023 13:09:01 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Florian Weimer <fweimer@redhat.com>
Cc:     Alexey Dobriyan <adobriyan@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
        linux-api@vger.kernel.org, x86@kernel.org
Subject: Re: [PATCH v2] ELF: supply userspace with available page shifts
 (AT_PAGE_SHIFT_MASK)
Message-ID: <202312061308.630C56CCA@keescook>
References: <6b399b86-a478-48b0-92a1-25240a8ede54@p183>
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 <1d679805-8a82-44a4-ba14-49d4f28ff597@p183>
 <202312061236.DE847C52AA@keescook>
 <87edfzavof.fsf@oldenburg.str.redhat.com>
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On Wed, Dec 06, 2023 at 10:05:36PM +0100, Florian Weimer wrote:
> * Kees Cook:
> 
> > On Tue, Dec 05, 2023 at 07:01:34PM +0300, Alexey Dobriyan wrote:
> >> Report available page shifts in arch independent manner, so that
> >> userspace developers won't have to parse /proc/cpuinfo hunting
> >> for arch specific strings:
> >> 
> >> Note!
> >> 
> >> This is strictly for userspace, if some page size is shutdown due
> >> to kernel command line option or CPU bug workaround, than is must not
> >> be reported in aux vector!
> >
> > Given Florian in CC, I assume this is something glibc would like to be
> > using? Please mention this in the commit log.
> 
> Nope, I just wrote a random drive-by comment on the first version.

Ah, okay. Then Alexey, who do you expect to be the consumer of this new
AT value?

-- 
Kees Cook