Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754158AbcDVJHv (ORCPT ); Fri, 22 Apr 2016 05:07:51 -0400 Received: from foss.arm.com ([217.140.101.70]:60160 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754090AbcDVJHs (ORCPT ); Fri, 22 Apr 2016 05:07:48 -0400 Date: Fri, 22 Apr 2016 10:07:45 +0100 From: Will Deacon To: Andrew Morton Cc: Ard Biesheuvel , linux-kernel@vger.kernel.org, linux-mm@kvack.org, lftan@altera.com, jonas@southpole.se Subject: Re: [PATCH resend 0/3] mm: allow arch to override lowmem_page_address Message-ID: <20160422090744.GB4236@arm.com> References: <1460995497-24312-1-git-send-email-ard.biesheuvel@linaro.org> <20160421165138.a57be293ec370d5ea014e1ae@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160421165138.a57be293ec370d5ea014e1ae@linux-foundation.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1626 Lines: 33 On Thu, Apr 21, 2016 at 04:51:38PM -0700, Andrew Morton wrote: > On Mon, 18 Apr 2016 18:04:54 +0200 Ard Biesheuvel wrote: > > > These patches allow the arch to define the page_to_virt() conversion that > > is used in lowmem_page_address(). This is desirable for arm64, where this > > conversion is trivial when CONFIG_SPARSEMEM_VMEMMAP is enabled, while > > breaking it up into __va(PFN_PHYS(page_to_pfn(page))), as is done currently > > in lowmem_page_address(), will force the use of a virt-to-phys() conversion > > and back again, which always involves a memory access on arm64, since the > > start of physical memory is not a compile time constant. > > > > I have split off these patches from my series 'arm64: optimize virt_to_page > > and page_address' which I sent out 3 weeks ago, and resending them in the > > hope that they can be picked up (with Will's ack on #3) to be merged via > > the mm tree. > > > > I have cc'ed the nios2 and openrisc maintainers on previous versions, and > > cc'ing them again now. I have dropped both of the arch specific mailing > > lists, since one is defunct and the other is subscriber only. > > > > Andrew, is this something you would be pulling to pick up (assuming that you > > agree with the contents)? Thanks. > > Looks OK to me and apart from the trivial openrisc/nios2 changes it's > obviously a no-op for all-but-arm. So I suggest you include these > patches in the appropriate arm tree. > > Acked-by: Andrew Morton Cracking, thanks Andrew. I'll queue these three in the arm64 tree and get them into -next. Will