From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH] x86: make IDT read-only
Date: Mon, 08 Apr 2013 15:48:21 -0700
Message-ID: <51634935.9010905@zytor.com>
References: <20130408224328.GA17641@www.outflux.net>
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To: Kees Cook <keescook@chromium.org>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>, Alex Shi <alex.shi@intel.com>, Jeremy Fitzhardinge <jeremy@goop.org>, Will Drewry <wad@chromium.org>, Julien Tinnes <jln@google.com>, Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>, Frederic Weisbecker <fweisbec@gmail.com>, Dan Rosenberg <drosenberg@vsecurity.com>, x86@kernel.org, linux-kernel@vger.kernel.org, Steven Rostedt <rostedt@goodmis.org>, Borislav Petkov <borislav.petkov@amd.com>, Ingo Molnar <mingo@redhat.com>, kernel-hardening@lists.openwall.com, Thomas Gleixner <tglx@linutronix.de>, "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>, virtualization@lists.linux-foundation.org, xen-devel@lists.xensource.com
List-Id: virtualization@lists.linuxfoundation.org

On 04/08/2013 03:43 PM, Kees Cook wrote:
> This makes the IDT unconditionally read-only. This primarily removes
> the IDT from being a target for arbitrary memory write attacks. It has
> an added benefit of also not leaking (via the "sidt" instruction) the
> kernel base offset, if it has been relocated.
> 
> Signed-off-by: Kees Cook <keescook@chromium.org>
> Cc: Eric Northup <digitaleric@google.com>

Also, tglx: does this interfere with your per-cpu IDT efforts?

	-hpa