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[209.132.180.67]) by mx.google.com with ESMTP id 3-v6si6420297pls.721.2018.02.26.01.03.45; Mon, 26 Feb 2018 01:03:59 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@virtuozzo.com header.s=selector1 header.b=NWfPPxsN; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=virtuozzo.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752424AbeBZJCk (ORCPT + 99 others); Mon, 26 Feb 2018 04:02:40 -0500 Received: from mail-db5eur01on0114.outbound.protection.outlook.com ([104.47.2.114]:45132 "EHLO EUR01-DB5-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752405AbeBZJCg (ORCPT ); Mon, 26 Feb 2018 04:02:36 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=virtuozzo.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version; bh=jcwdpwQhqWXcluh3wQbagvNVW61MOMKEsVrnB3Xd0W0=; b=NWfPPxsNg4WKlkNwnb8VTvCkuvwRxlOVosn/7/SX8UY2gNamunNoleCo8Wan1HiwvKrdTH8CFAhOuGyy+T+pSqu6OesLql5Ih3/rclkESShZYK7kWjjjrCIzTgW6aWio2MIzvaJUAcb0dni5USdlB+8553JBeBgJtJioe8sQOfw= Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=xemul@virtuozzo.com; Received: from [172.16.24.160] (195.214.232.6) by AM4PR0802MB2129.eurprd08.prod.outlook.com (2603:10a6:200:5c::20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.527.15; Mon, 26 Feb 2018 09:02:31 +0000 Subject: Re: [PATCH v5 0/4] vm: add a syscall to map a process memory into a pipe To: Andrew Morton , Mike Rapoport Cc: Alexander Viro , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, criu@openvz.org, gdb@sourceware.org, devel@lists.open-mpi.org, rr-dev@mozilla.org, Arnd Bergmann , Michael Kerrisk , Thomas Gleixner , Josh Triplett , Jann Horn , Greg KH , Andrei Vagin References: <1515479453-14672-1-git-send-email-rppt@linux.vnet.ibm.com> <20180220164406.3ec34509376f16841dc66e34@linux-foundation.org> From: Pavel Emelyanov Message-ID: <3122ec5a-7f73-f6b4-33ea-8c10ef32e5b0@virtuozzo.com> Date: Mon, 26 Feb 2018 12:02:25 +0300 User-Agent: Mozilla/5.0 (X11; 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The big question is: do we know that > people will actually use this, and get sufficient value from it to > justify its addition? Yes, that's what bothers us a lot too :) I've tried to start with finding out if anyone used the sys_read/write_process_vm() calls, but failed :( Does anybody know how popular these syscalls are? If its users operate on big amount of memory, they could benefit from the proposed splice extension. -- Pavel