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Date:   Fri, 23 Nov 2018 10:40:52 -0600
From:   Josh Poimboeuf <jpoimboe@redhat.com>
To:     Ingo Molnar <mingo@kernel.org>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>, pabeni@redhat.com,
        Jens Axboe <axboe@kernel.dk>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, bp@alien8.de,
        Peter Anvin <hpa@zytor.com>,
        the arch/x86 maintainers <x86@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Andrew Lutomirski <luto@kernel.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>, dvlasenk@redhat.com,
        brgerst@gmail.com,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] x86: only use ERMS for user copies for larger sizes
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On Thu, Nov 22, 2018 at 12:13:41PM +0100, Ingo Molnar wrote:
> Note to self: watch out for patches that change altinstructions and don't 
> make premature vmlinux size impact assumptions. :-)

I noticed a similar problem with ORC data.  As it turns out, size's
"text" calculation also includes read-only sections.  That includes
.rodata and anything else not writable.

Maybe we need a more sensible "size" script for the kernel.  It would be
trivial to implement based on the output of "readelf -S vmlinux".

-- 
Josh