From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f69.google.com (mail-oi0-f69.google.com [209.85.218.69]) by kanga.kvack.org (Postfix) with ESMTP id 8006E6B0005 for ; Tue, 2 Aug 2016 07:00:46 -0400 (EDT) Received: by mail-oi0-f69.google.com with SMTP id w207so356376937oiw.1 for ; Tue, 02 Aug 2016 04:00:46 -0700 (PDT) Received: from EUR01-DB5-obe.outbound.protection.outlook.com (mail-db5eur01on0093.outbound.protection.outlook.com. [104.47.2.93]) by mx.google.com with ESMTPS id p22si1006937otd.125.2016.08.02.04.00.44 for (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 02 Aug 2016 04:00:45 -0700 (PDT) Subject: Re: [PATCHv2 3/6] x86/arch_prctl/vdso: add ARCH_MAP_VDSO_* References: <20160629105736.15017-1-dsafonov@virtuozzo.com> <20160629105736.15017-4-dsafonov@virtuozzo.com> <20160711182654.GA19160@redhat.com> <20160712141446.GB28837@redhat.com> From: Dmitry Safonov Message-ID: Date: Tue, 2 Aug 2016 13:59:40 +0300 MIME-Version: 1.0 In-Reply-To: <20160712141446.GB28837@redhat.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Oleg Nesterov , Andy Lutomirski Cc: Michal Hocko , Vladimir Davydov , "linux-kernel@vger.kernel.org" , Dmitry Safonov <0x7f454c46@gmail.com>, "linux-mm@kvack.org" , Ingo Molnar , Cyrill Gorcunov , xemul@virtuozzo.com, Andy Lutomirski , Thomas Gleixner , "H. Peter Anvin" , X86 ML On 07/12/2016 05:14 PM, Oleg Nesterov wrote: > On 07/11, Andy Lutomirski wrote: >> I'm starting to wonder if we should finally suck it up and give >> special mappings a non-NULL vm_file so we can track them properly. >> Oleg, weren't you thinking of doing that for some other reason? > > Yes, uprobes. Currently we can't probe vdso page(s). So, to make sure, that I've understood correctly, I need to: o add vm_file to vdso/vvar vmas, __install_special_mapping will init them; o place array pages[] inside f_mapping; o create f_inode for each file -- for this we need some mount point, so I'll create something like vdsofs, register this filesystem and mount it in initcall (or like do_basic_setup - as it's done by shmem, i.e). Is this the idea, or I got it wrong? And maybe the idea is to create fake vm_file for just reference counting, but do not treat/init it like file with inode, etc? So with fake file I can also check if vdso is mapped already, but I'm sure the fake file will not help Oleg with uprobes. -- Dmitry -- 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