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Date: Tue, 17 Mar 2015 15:41:33 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Steven Rostedt <rostedt@goodmis.org>, Borislav Petkov <bp@alien8.de>,
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        Kees Cook <keescook@chromium.org>, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] x86/asm/entry/64: Remove unused thread_struct::usersp
Message-ID: <20150317144133.GB18462@gmail.com>
References: <1426599779-8010-1-git-send-email-dvlasenk@redhat.com>
 <1426599779-8010-2-git-send-email-dvlasenk@redhat.com>
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* Denys Vlasenko <dvlasenk@redhat.com> wrote:

> All manipulations of PER_CPU(old_rsp) in C code are removed:
> it is not used on SYSRET return, so storing anything there is
> pointless.
> 
> This also allows us to get rid of thread_struct::usersp,
> which was needed only to set PER_CPU(old_rsp) for correct
> return from fork/clone.
> 
> Tweak a few comments as well: we no longer have "partial stack frame",
> ever.

So this doesn't really explain it very well, plus it still 
unnecessarily mixes up two changes in a single patch: please
don't do that!

I've fixed it all up and split up the patch into two, easier
to bisect parts.

Thanks,

	Ingo