From mboxrd@z Thu Jan 1 00:00:00 1970 From: KOSAKI Motohiro Subject: Re: Arch specific mmap attributes (Was: mprotect pgprot handling weirdness) Date: Tue, 6 Apr 2010 19:26:01 +0900 (JST) Message-ID: <20100406185246.7E63.A69D9226@jp.fujitsu.com> References: <20100406151751.7E4E.A69D9226@jp.fujitsu.com> <1270539044.13812.65.camel@pasglop> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Return-path: Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:52781 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751682Ab0DFK0I (ORCPT ); Tue, 6 Apr 2010 06:26:08 -0400 In-Reply-To: <1270539044.13812.65.camel@pasglop> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Benjamin Herrenschmidt Cc: kosaki.motohiro@jp.fujitsu.com, linux-mm@kvack.org, "linux-kernel@vger.kernel.org" , linux-arch@vger.kernel.org > Ok, I see. No biggie. The main deal remains how we want to do that > inside the kernel :-) I think the less horrible options here are > to either extend vm_flags to always be 64-bit, or add a separate > vm_map_attributes flag, and add the necessary bits and pieces to > prevent merge accross different attribute vma's. vma->vm_flags already have VM_SAO. Why do we need more flags? At least, I dislike to add separate flags member into vma. It might introduce unnecessary messy into vma merge thing. > The more I try to hack it into vm_page_prot, the more I hate that > option.