From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934961AbdBQVBZ (ORCPT ); Fri, 17 Feb 2017 16:01:25 -0500 Received: from mail-oi0-f65.google.com ([209.85.218.65]:33698 "EHLO mail-oi0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934271AbdBQVBX (ORCPT ); Fri, 17 Feb 2017 16:01:23 -0500 MIME-Version: 1.0 In-Reply-To: References: <20170217141328.164563-1-kirill.shutemov@linux.intel.com> <20170217141328.164563-34-kirill.shutemov@linux.intel.com> From: Linus Torvalds Date: Fri, 17 Feb 2017 13:01:21 -0800 X-Google-Sender-Auth: FNYeJ8wUecSgayw2Z91D980162E Message-ID: Subject: Re: [PATCHv3 33/33] mm, x86: introduce PR_SET_MAX_VADDR and PR_GET_MAX_VADDR To: Andy Lutomirski Cc: "Kirill A. Shutemov" , Andrew Morton , "the arch/x86 maintainers" , Thomas Gleixner , Ingo Molnar , Arnd Bergmann , "H. Peter Anvin" , Andi Kleen , Dave Hansen , "linux-arch@vger.kernel.org" , linux-mm , Linux Kernel Mailing List , Catalin Marinas , Linux API Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 17, 2017 at 12:12 PM, Andy Lutomirski wrote: > > At the very least, I'd want to see > MAP_FIXED_BUT_DONT_BLOODY_UNMAP_ANYTHING. I *hate* the current > interface. That's unrelated, but I guess w could add a MAP_NOUNMAP flag, and then you can use MAP_FIXED | MAP_NOUNMAP or something. But that has nothing to do with the 47-vs-56 bit issue. > How about MAP_LIMIT where the address passed in is interpreted as an > upper bound instead of a fixed address? Again, that's a unrelated semantic issue. Right now - if you don't pass in MAP_FIXED at all, the "addr" argument is used as a starting value for deciding where to find an unmapped area. But there is no way to specify the end. That would basically be what the process control thing would be (not per-system-call, but per-thread ). Linus From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ot0-f200.google.com (mail-ot0-f200.google.com [74.125.82.200]) by kanga.kvack.org (Postfix) with ESMTP id B9FCE6B0038 for ; Fri, 17 Feb 2017 16:01:22 -0500 (EST) Received: by mail-ot0-f200.google.com with SMTP id 45so41973918otd.6 for ; Fri, 17 Feb 2017 13:01:22 -0800 (PST) Received: from mail-oi0-x244.google.com (mail-oi0-x244.google.com. [2607:f8b0:4003:c06::244]) by mx.google.com with ESMTPS id f24si1514040ote.213.2017.02.17.13.01.22 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 17 Feb 2017 13:01:22 -0800 (PST) Received: by mail-oi0-x244.google.com with SMTP id e123so110583oig.0 for ; Fri, 17 Feb 2017 13:01:22 -0800 (PST) MIME-Version: 1.0 In-Reply-To: References: <20170217141328.164563-1-kirill.shutemov@linux.intel.com> <20170217141328.164563-34-kirill.shutemov@linux.intel.com> From: Linus Torvalds Date: Fri, 17 Feb 2017 13:01:21 -0800 Message-ID: Subject: Re: [PATCHv3 33/33] mm, x86: introduce PR_SET_MAX_VADDR and PR_GET_MAX_VADDR Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Andy Lutomirski Cc: "Kirill A. Shutemov" , Andrew Morton , the arch/x86 maintainers , Thomas Gleixner , Ingo Molnar , Arnd Bergmann , "H. Peter Anvin" , Andi Kleen , Dave Hansen , "linux-arch@vger.kernel.org" , linux-mm , Linux Kernel Mailing List , Catalin Marinas , Linux API On Fri, Feb 17, 2017 at 12:12 PM, Andy Lutomirski wrote: > > At the very least, I'd want to see > MAP_FIXED_BUT_DONT_BLOODY_UNMAP_ANYTHING. I *hate* the current > interface. That's unrelated, but I guess w could add a MAP_NOUNMAP flag, and then you can use MAP_FIXED | MAP_NOUNMAP or something. But that has nothing to do with the 47-vs-56 bit issue. > How about MAP_LIMIT where the address passed in is interpreted as an > upper bound instead of a fixed address? Again, that's a unrelated semantic issue. Right now - if you don't pass in MAP_FIXED at all, the "addr" argument is used as a starting value for deciding where to find an unmapped area. But there is no way to specify the end. That would basically be what the process control thing would be (not per-system-call, but per-thread ). Linus -- 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