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From: Borislav Petkov <bp@alien8.de>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Ben Harris <bjh21@bjh21.me.uk>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
	x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86: Don't allow stackprotector without TSC
Date: Fri, 24 Oct 2014 14:03:23 +0200	[thread overview]
Message-ID: <20141024120323.GA30459@pd.tnic> (raw)
In-Reply-To: <54499287.5070803@amacapital.net>

On Thu, Oct 23, 2014 at 04:43:03PM -0700, Andy Lutomirski wrote:
> Presumably the actual failure is a #GP when trying to do the rdtsc. If
> so, wouldn't a better fix be to make that rdtsc check cpuid first? Can
> we easily check cpuid that early?

I don't see why not.

The real question, though is, can we have a fallback for RDTSC on those
machines so that they don't have to disable stack protector in order to
boot.

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
--

  reply	other threads:[~2014-10-24 12:03 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-23 22:10 [PATCH] x86: Don't allow stackprotector without TSC Ben Harris
2014-10-23 23:43 ` Andy Lutomirski
2014-10-24 12:03   ` Borislav Petkov [this message]
2014-10-25 21:31     ` Thomas Gleixner

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