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Date: Thu, 22 May 2014 00:17:28 +0200
From: Borislav Petkov <bp@alien8.de>
To: Andy Lutomirski <luto@amacapital.net>
Cc: "Luck, Tony" <tony.luck@intel.com>, Jiri Kosina <jkosina@suse.cz>,
        Thomas Gleixner <tglx@linutronix.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@kernel.org>
Subject: Re: [RFC] x86_64: A real proposal for iret-less return to kernel
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On Wed, May 21, 2014 at 03:13:16PM -0700, Andy Lutomirski wrote:
> Why is this necessary?
> 
> If the MCE hit kernel code, then we're going to die anyway.  If the
> MCE hit user code, then we should be in a completely sensible context
> and we can just send the signal.

Are we guaranteed that the first thing the process will execute when
scheduled back in are the signal handlers?

And besides, maybe we don't even want to allow to do the switch_to() but
kill it while it is sleeping.

(I know, we're that nasty :-))

-- 
Regards/Gruss,
    Boris.

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