Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Mon, 12 Feb 2018 18:05:10 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Kees Cook <keescook@chromium.org>
Cc:     David Woodhouse <dwmw2@infradead.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Ulf Magnusson <ulfalizer@gmail.com>,
        Masahiro Yamada <yamada.masahiro@socionext.com>,
        Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Nicolas Pitre <nicolas.pitre@linaro.org>,
        "Luis R . Rodriguez" <mcgrof@suse.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Sam Ravnborg <sam@ravnborg.org>,
        Michal Marek <michal.lkml@markovi.net>,
        Martin Schwidefsky <schwidefsky@de.ibm.com>,
        Pavel Machek <pavel@ucw.cz>,
        linux-s390 <linux-s390@vger.kernel.org>,
        Jiri Kosina <jkosina@suse.cz>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Tejun Heo <tj@kernel.org>, Ingo Molnar <mingo@kernel.org>,
        "Van De Ven, Arjan" <arjan.van.de.ven@intel.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [RFC PATCH 4/7] kconfig: support new special property shell=
Message-ID: <20180212170510.GQ25181@hirez.programming.kicks-ass.net>
References: <CA+55aFz-SJ970iqDsR8-Ke4z6WvB4n9RXAeen8pG=+YJWubETw@mail.gmail.com>
 <CAGXu5jLo0iuMsH89vj3nr8sv+1YvXfXgoPeBdxHwZm5i=DWoOA@mail.gmail.com>
 <CA+55aFxdx3FYE6YGifRR=BSG9QzXwgThj5z7RmV5P5+RpNXSiQ@mail.gmail.com>
 <CA+55aFyPyYyG-riaBQU5cGp_sC=r8mf9Mg6L=DUEH6EyQfWYwA@mail.gmail.com>
 <20180211103432.pf2ot6nd7nbhdhsy@huvuddator>
 <CAGXu5jLtFcvbazxUvL_=6uT+a8m0JQEB7v0OE41Z-PMoX_fWpA@mail.gmail.com>
 <CA+55aFz3gUKQMr-X-b=ytLPX0AjGUaXNtLSUQ0_xZwZuDU33RQ@mail.gmail.com>
 <20180212082635.GA25314@hirez.programming.kicks-ass.net>
 <1518452362.6606.102.camel@infradead.org>
 <CAGXu5jLdH7wkrnB9YnRLf+vQsQyfHehUywkXqsBuy6WmVLH3OA@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAGXu5jLdH7wkrnB9YnRLf+vQsQyfHehUywkXqsBuy6WmVLH3OA@mail.gmail.com>
User-Agent: Mutt/1.9.2 (2017-12-15)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Mon, Feb 12, 2018 at 08:56:31AM -0800, Kees Cook wrote:
> That would be bad: Android exclusively builds with clang.

So implement asm-goto already, and do asm-cc-output while you're at it.

The whole asm-goto/jump_label stuff really does make a measureable
difference in performance, and its bloody rediculous LLVM doesn't have
it.

And no, a different interface to do something similar is not OK. We're
not going to have a second implementation of jump-labels and everything
else that uses it.