From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753372AbaIXP6S (ORCPT ); Wed, 24 Sep 2014 11:58:18 -0400 Received: from outbound-smtp05.blacknight.com ([81.17.249.38]:36716 "EHLO outbound-smtp05.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752942AbaIXP6O (ORCPT ); Wed, 24 Sep 2014 11:58:14 -0400 Message-ID: <5422EA13.1080706@nexus-software.ie> Date: Wed, 24 Sep 2014 16:58:11 +0100 From: "Bryan O'Donoghue" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.1.1 MIME-Version: 1.0 To: "H. Peter Anvin" , mingo@kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, stable@vger.kernel.org, bp@alien8.de, linux-tip-commits@vger.kernel.org Subject: Re: [tip:x86/platform] x86/intel/quark: Switch off CR4.PGE so TLB flush uses CR3 instead References: <1411514784-14885-1-git-send-email-pure.logic@nexus-software.ie> <5422E8D0.5080705@zytor.com> In-Reply-To: <5422E8D0.5080705@zytor.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > I believe there is one more change needed: there is a __flush_tlb_all() > in the early code which gets executed before the above code runs; the > easiest fix is to just add a __flush_tlb() immediately after it. > > This should have been pushed upstream, and not stayed in the BSP kernel. Peter. You're talking about void __init setup_arch() right ? The code looks like this load_cr3(swapper_pg_dir); __flush_tlb_all(); Note that on Quark the method to invalidate the TLB is by reloading CR3 - which is immediately prior to __flush_tlb_all(); So __flush_tlb_all(); will do nothing but that's OK since load_cr3() already flushed the TLB - including any PTE with PGE set Best, Bryan