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From: Andy Lutomirski <luto@amacapital.net>
Date: Tue, 28 Jul 2015 08:23:04 -0700
Message-ID: <CALCETrX4aBxf_apw8oqb_jM_NWp4mSa_8enP_zwF_DX01Dnsiw@mail.gmail.com>
Subject: Re: [PATCH v8 09/21] x86/paravirt: Align paravirt thunk functions at
 16-byte boundaries
To: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Michal Marek <mmarek@suse.cz>,
        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>, Borislav Petkov <bp@alien8.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andi Kleen <andi@firstfloor.org>, Pedro Alves <palves@redhat.com>,
        Namhyung Kim <namhyung@gmail.com>,
        Bernd Petrovitsch <bernd@petrovitsch.priv.at>, X86 ML <x86@kernel.org>,
        live-patching@vger.kernel.org,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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On Tue, Jul 28, 2015 at 7:47 AM, Josh Poimboeuf <jpoimboe@redhat.com> wrote:
> Paravirt thunk functions aren't aligned, which can impact performance
> and is inconsistent with gcc-generated functions.
>
> Align them at 16-byte boundaries to be consistent with gcc functions.

IMO stackvalidate shouldn't warn about this.  We've discussed dropping
the alignment requirement entirely, since it seems to have little
benefit on modern CPUs.

--Andy
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