Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754010AbbLKWdD (ORCPT ); Fri, 11 Dec 2015 17:33:03 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:51675 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753277AbbLKWdB (ORCPT ); Fri, 11 Dec 2015 17:33:01 -0500 Date: Fri, 11 Dec 2015 14:33:00 -0800 From: Andrew Morton To: Andy Lutomirski Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 2/6] mm: Add vm_insert_pfn_prot Message-Id: <20151211143300.0ac516fbd219a67954698f9a@linux-foundation.org> In-Reply-To: References: X-Mailer: Sylpheed 3.4.1 (GTK+ 2.24.23; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 918 Lines: 24 On Thu, 10 Dec 2015 19:21:43 -0800 Andy Lutomirski wrote: > The x86 vvar mapping contains pages with differing cacheability > flags. This is currently only supported using (io_)remap_pfn_range, > but those functions can't be used inside page faults. Foggy. What does "support" mean here? > Add vm_insert_pfn_prot to support varying cacheability within the > same non-COW VMA in a more sane manner. Here, "support" presumably means "insertion of pfns". Can we spell all this out more completely please? > x86 needs this to avoid a CRIU-breaking and memory-wasting explosion > of VMAs when supporting userspace access to the HPET. > OtherwiseAck. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/