Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756144AbaFYVnP (ORCPT ); Wed, 25 Jun 2014 17:43:15 -0400 Received: from mga02.intel.com ([134.134.136.20]:34504 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754995AbaFYVnO (ORCPT ); Wed, 25 Jun 2014 17:43:14 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.01,548,1400050800"; d="scan'208";a="563476439" Message-ID: <53AB4271.6040301@intel.com> Date: Wed, 25 Jun 2014 14:43:13 -0700 From: Dave Hansen User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Andy Lutomirski , "Ren, Qiaowei" CC: "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , X86 ML , "linux-kernel@vger.kernel.org" , Linux MM Subject: Re: [PATCH v6 02/10] x86, mpx: add MPX specific mmap interface References: <1403084656-27284-1-git-send-email-qiaowei.ren@intel.com> <1403084656-27284-3-git-send-email-qiaowei.ren@intel.com> <53A884B2.5070702@mit.edu> <53A88806.1060908@intel.com> <53A88DE4.8050107@intel.com> <9E0BE1322F2F2246BD820DA9FC397ADE016AF41C@shsmsx102.ccr.corp.intel.com> <9E0BE1322F2F2246BD820DA9FC397ADE016B26AB@shsmsx102.ccr.corp.intel.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/25/2014 02:04 PM, Andy Lutomirski wrote: > On Tue, Jun 24, 2014 at 6:40 PM, Ren, Qiaowei wrote: >> Hmm, _install_special_mapping should completely prevent merging, even among MPX vmas. >> >> So, could you tell me how to set MPX specific ->name to the vma when it is created? Seems like that I could not find such interface. > > You may need to add one. > > I'd suggest posting a new thread to linux-mm describing what you need > and asking how to do it. I shared this with Qiaowei privately, but might as well repeat myself here in case anyone wants to set me straight. Most of the interfaces do to set vm_ops do it in file_operations ->mmap op. Nobody sets ->vm_ops on anonymous VMAs, so we're in uncharted territory. My suggestion: you can either plumb a new API down in to mmap_region() to get the VMA or set ->vm_ops, or just call find_vma() after mmap_region() or get_unmapped_area() and set it manually. Just make sure you still have mmap_sem held over the whole thing. I think I prefer just setting ->vm_ops directly, even though it's a wee bit of a hack to create something just to look it up a moment later. Oh, well. -- 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/