Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752817AbbFHMxq (ORCPT ); Mon, 8 Jun 2015 08:53:46 -0400 Received: from mail-la0-f43.google.com ([209.85.215.43]:35791 "EHLO mail-la0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752013AbbFHMxi (ORCPT ); Mon, 8 Jun 2015 08:53:38 -0400 MIME-Version: 1.0 In-Reply-To: References: <20150512090156.24768.2521.stgit@buzz> Date: Mon, 8 Jun 2015 13:53:36 +0100 Message-ID: Subject: Re: [PATCH RFC 0/3] pagemap: make useable for non-privilege users From: Mark Williamson To: Konstantin Khlebnikov Cc: linux-mm@kvack.org, Naoya Horiguchi , kernel list , Andrew Morton , Pavel Emelyanov , Linux API , Andy Lutomirski , Vlastimil Babka , Pavel Machek , Mark Seaborn , "Kirill A. Shutemov" , Linus Torvalds , Daniel James , Finn Grimwood Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2522 Lines: 68 Hi Konstantin, Would you still be intending to re-submit this patch? We'd be quite keen to assist, so if there's anything further I can do please let me know! Just to re-confirm - we do think that the patch will solve our problem (relatively minor changes required on our side). Thanks, Mark On Thu, May 14, 2015 at 7:40 PM, Mark Williamson wrote: > Hi Konstantin, > > I modified our code to check for the map-exclusive flag where it used > to compare pageframe numbers. First tests look pretty promising, so > this patch looks like a viable approach for us. > > Is there anything further we can do to help? > > Thanks, > Mark > > On Tue, May 12, 2015 at 12:13 PM, Mark Williamson > wrote: >> Hi Konstantin, >> >> Thanks very much for continuing to look at this! It's very much >> appreciated. I've been investigating from our end but got caught up >> in some gnarly details of our pagemap-consuming code. >> >> I like the approach and it seems like the information you're exposing >> will be useful for our application. I'll test the patch and see if it >> works for us as-is. >> >> Will follow up with any comments on the individual patches. >> >> Thanks, >> Mark >> >> On Tue, May 12, 2015 at 10:43 AM, Konstantin Khlebnikov >> wrote: >>> This patchset tries to make pagemap useable again in the safe way. >>> First patch adds bit 'map-exlusive' which is set if page is mapped only here. >>> Second patch restores access for non-privileged users but hides pfn if task >>> has no capability CAP_SYS_ADMIN. Third patch removes page-shift bits and >>> completes migration to the new pagemap format (flags soft-dirty and >>> mmap-exlusive are available only in the new format). >>> >>> --- >>> >>> Konstantin Khlebnikov (3): >>> pagemap: add mmap-exclusive bit for marking pages mapped only here >>> pagemap: hide physical addresses from non-privileged users >>> pagemap: switch to the new format and do some cleanup >>> >>> >>> Documentation/vm/pagemap.txt | 3 - >>> fs/proc/task_mmu.c | 178 +++++++++++++++++------------------------- >>> tools/vm/page-types.c | 35 ++++---- >>> 3 files changed, 91 insertions(+), 125 deletions(-) -- 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/