From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-vk0-f71.google.com (mail-vk0-f71.google.com [209.85.213.71]) by kanga.kvack.org (Postfix) with ESMTP id B1C4E6B0038 for ; Fri, 17 Feb 2017 18:02:55 -0500 (EST) Received: by mail-vk0-f71.google.com with SMTP id 23so31358460vkc.1 for ; Fri, 17 Feb 2017 15:02:55 -0800 (PST) Received: from mail-vk0-x22c.google.com (mail-vk0-x22c.google.com. [2607:f8b0:400c:c05::22c]) by mx.google.com with ESMTPS id x132si3632202vkc.43.2017.02.17.15.02.54 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 17 Feb 2017 15:02:54 -0800 (PST) Received: by mail-vk0-x22c.google.com with SMTP id r136so37576932vke.1 for ; Fri, 17 Feb 2017 15:02:54 -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: Andy Lutomirski Date: Fri, 17 Feb 2017 15:02:33 -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: Linus Torvalds 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 1:01 PM, Linus Torvalds wrote: > 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 ). > What I'm trying to say is: if we're going to do the route of 48-bit limit unless a specific mmap call requests otherwise, can we at least have an interface that doesn't suck? -- 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