From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756133Ab2FFOhq (ORCPT ); Wed, 6 Jun 2012 10:37:46 -0400 Received: from mga03.intel.com ([143.182.124.21]:11641 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755849Ab2FFOho (ORCPT ); Wed, 6 Jun 2012 10:37:44 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.71,315,1320652800"; d="scan'208";a="108542074" Date: Wed, 6 Jun 2012 07:37:43 -0700 From: Andi Kleen To: Peter Zijlstra Cc: Andi Kleen , linux-kernel@vger.kernel.org, eranian@google.com Subject: Re: [PATCH 3/5] perf, x86: Check LBR format capability Message-ID: <20120606143743.GI28225@tassilo.jf.intel.com> References: <1338944211-28275-1-git-send-email-andi@firstfloor.org> <1338944211-28275-3-git-send-email-andi@firstfloor.org> <1338979224.2749.93.camel@twins> <20120606141419.GE28225@tassilo.jf.intel.com> <1338992556.2749.118.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1338992556.2749.118.camel@twins> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 06, 2012 at 04:22:36PM +0200, Peter Zijlstra wrote: > On Wed, 2012-06-06 at 07:14 -0700, Andi Kleen wrote: > > On Wed, Jun 06, 2012 at 12:40:24PM +0200, Peter Zijlstra wrote: > > > On Tue, 2012-06-05 at 17:56 -0700, Andi Kleen wrote: > > > > From: Andi Kleen > > > > > > > > Double check the CPU has a LBR format we support before using it. > > > > > > > > Also I made the init functions __init while I was on it. > > > > > > Why? Its all after a model test anyway. > > > > Because the spec says we should check it. > > The spec says lots of things.. but being that LBR is very much model > specific I really can't be bothered. Well you don't need to be, I did it already :-) > > > It could catch bad VMs and other inconsistencies and it's the right thing > > to do. > > That might be a reason, but does it?, and why wasn't that in the > changelog? No it will not catch KVM because zero is a valid version :-/ That would still need the MISC_ENABLE re-read I think. Still it's the right thing to do I believe. -andi -- ak@linux.intel.com -- Speaking for myself only