From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f42.google.com (mail-pa0-f42.google.com [209.85.220.42]) by kanga.kvack.org (Postfix) with ESMTP id 82AC16B0253 for ; Fri, 11 Dec 2015 17:33:02 -0500 (EST) Received: by padhk6 with SMTP id hk6so31720644pad.2 for ; Fri, 11 Dec 2015 14:33:02 -0800 (PST) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTPS id bf7si3784542pad.239.2015.12.11.14.33.01 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 11 Dec 2015 14:33:01 -0800 (PST) Date: Fri, 11 Dec 2015 14:33:00 -0800 From: Andrew Morton Subject: Re: [PATCH 2/6] mm: Add vm_insert_pfn_prot Message-Id: <20151211143300.0ac516fbd219a67954698f9a@linux-foundation.org> In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andy Lutomirski Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org