Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932482AbdIGSoT (ORCPT ); Thu, 7 Sep 2017 14:44:19 -0400 Received: from mail-it0-f50.google.com ([209.85.214.50]:38424 "EHLO mail-it0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932415AbdIGSoR (ORCPT ); Thu, 7 Sep 2017 14:44:17 -0400 X-Google-Smtp-Source: ADKCNb4eGFt5tTo0GwE1qlupl5LYcicfnM1EtNux6cVgNpwL57QgE5+f0QXpoB/d4qFqZYmhaXH48A== Date: Thu, 7 Sep 2017 12:44:14 -0600 From: Tycho Andersen To: Christoph Hellwig Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, kernel-hardening@lists.openwall.com, Marco Benatto , Juerg Haefliger , Konrad Rzeszutek Wilk Subject: Re: [PATCH v6 04/11] swiotlb: Map the buffer if it was unmapped by XPFO Message-ID: <20170907184414.ow7av6wt5vht6pnd@docker> References: <20170907173609.22696-1-tycho@docker.com> <20170907173609.22696-5-tycho@docker.com> <20170907181015.GA9557@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170907181015.GA9557@infradead.org> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 555 Lines: 19 On Thu, Sep 07, 2017 at 11:10:15AM -0700, Christoph Hellwig wrote: > > - if (PageHighMem(pfn_to_page(pfn))) { > > + if (PageHighMem(page) || xpfo_page_is_unmapped(page)) { > > Please don't sprinkle xpfo details over various bits of code. > > Just add a helper with a descriptive name, e.g. > > page_is_unmapped() > > that also includes the highmem case, as that will easily document > what this check is doing. Will do, thanks. Patch 7 has a similar feel to this one, I can add a wrapper around __clean_dcache_area_pou() if that makes sense? Tycho