From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759473Ab3BYO6H (ORCPT ); Mon, 25 Feb 2013 09:58:07 -0500 Received: from e8.ny.us.ibm.com ([32.97.182.138]:59960 "EHLO e8.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751661Ab3BYO6C (ORCPT ); Mon, 25 Feb 2013 09:58:02 -0500 Message-ID: <512B784E.5070002@linux.vnet.ibm.com> Date: Mon, 25 Feb 2013 06:42:22 -0800 From: Dave Hansen User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Peter Hurley CC: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Gleb Natapov , "H. Peter Anvin" , x86@kernel.org, Marcelo Tosatti , Rik van Riel Subject: Re: [PATCH 0/5] [v3] fix illegal use of __pa() in KVM code References: <20130122212428.8DF70119@kernel.stglabs.ibm.com> <1361741338.21499.38.camel@thor.lan> In-Reply-To: <1361741338.21499.38.camel@thor.lan> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13022514-9360-0000-0000-00001109284B Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/24/2013 01:28 PM, Peter Hurley wrote: > Now that the alloc_remap() has been/is being removed, is most/all of > this being reverted? I _believe_ alloc_remap() is the only case where we actually remapped low memory. However, there is still other code that does __pa() translations for percpu areas: per_cpu_ptr_to_phys(). I _think_ it's still theoretically possible to get some percpu data in the vmalloc() area. > So in short, my questions are: > 1) is the slow_virt_to_phys() necessary anymore? kvm_vcpu_arch has a struct pvclock_vcpu_time_info hv_clock; and I believe I mistook the two 'hv_clock's for each other. However, this doesn't hurt anything, and the performance difference is probably horribly tiny.