From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7EBDFC4321A for ; Sat, 29 Jun 2019 10:22:06 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0BDD9214AF for ; Sat, 29 Jun 2019 10:22:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (4096-bit key) header.d=crudebyte.com header.i=@crudebyte.com header.b="bNyUfn6Z" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0BDD9214AF Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=nongnu.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:38672 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hhAUe-0001NW-Ut for qemu-devel@archiver.kernel.org; Sat, 29 Jun 2019 06:22:04 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:44447) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hhATc-0000ls-9P for qemu-devel@nongnu.org; Sat, 29 Jun 2019 06:21:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hhATb-0005Gg-8E for qemu-devel@nongnu.org; Sat, 29 Jun 2019 06:21:00 -0400 Received: from kylie.crudebyte.com ([5.189.157.229]:41875) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hhATa-0005DH-Nn for qemu-devel@nongnu.org; Sat, 29 Jun 2019 06:20:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=crudebyte.com; s=kylie; h=Content-Type:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=XPc9tVsZC9+q0LC9Nw2tscTqstUx0oDgtuFZBuVC8co=; b=bNyUfn6ZIsVmnwGL5DJVR/HBxH VNWfosGuyuAOaTJIHJ60GzZ1EyqqXxPYWkRah9F6DXWn8YhSENPbSY4wX+72K1GAZgTBo2N4FUR78 NOX0GqpkmDwgqstq1qXiDQMwk+pXw3ni7kZ2OWROv/rMG0800WKhWWnGTvrwhpDpr5NooFvdJ7mm3 WeSaVy58ImknWKEaE5jLFsDF73WddQ4D6xKK/JCx5+4dxHVO0Oef1/JPuNJt5B2202p9kj0AH4BPU qDn+MFghg4kawPe6XmyTSL1UTv1s8BpMFHPnykySqXL+R2GuJC9yAWF4gUogNBcZK+3um66rVOIZ+ pSS3bSaO1KBT3G0yMBPCy02pnd8me7PaF/xrrIXVT7HWso1lFwUfytkHrnqierxxT4AhXlm1wtHYL fPL3eHuvsoILKNgNqoUNvZOKgmK4MidjNkjdaPdgdYmMNEmytL+GjBlu2SfMqzpIou1gRO9bcynpe qF6rJIUOFjXqR0JYVArwolyrV5ZZU5N66GXtFIOjr5XPQS9XYNzCjfEgrYpv33OViyLK1MoTuPiA4 Dju0Y8zH+DTVLfGfHfpVL1oTwAK8il5dBDPqYXfdE3XEl0vP67GKrvoKVB/vSTgMoTj1CDlWdHXtt vofH79qawOC1bEsfd3fqwcrzpwwV0BxCgh5Y3cpy8=; To: qemu-devel@nongnu.org Date: Sat, 29 Jun 2019 12:20:49 +0200 Message-ID: <10483682.05G6IJrOKK@silver> In-Reply-To: <20190628162308.40ec742c@bahia.lan> References: <4068711.1y5nem0Q7a@silver> <20190628162308.40ec742c@bahia.lan> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 5.189.157.229 Subject: Re: [Qemu-devel] [PATCH v4 3/5] 9p: Added virtfs option "remap_inodes" X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Christian Schoenebeck via Qemu-devel Reply-To: Christian Schoenebeck Cc: Daniel =?ISO-8859-1?Q?P=2E_Berrang=E9?= , Christian Schoenebeck , Greg Kurz , Antonios Motakis Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Freitag, 28. Juni 2019 16:23:08 CEST Greg Kurz wrote: > > > This feature applies to all backends IIUC. We don't really care for the > > > synth backend since it generates non-colliding inode numbers by design, > > > but the proxy backend has the same issue as local. So... > > > > Yeah, I was not sure about these, because I did not even know what these > > two were for exactly. :) [ lazyness disclaimer end] > > "proxy" is a backend where all I/O accesses are performed by a separate > process running the virtfs-proxy-helper command. It runs with root > privileges, which provides the same level of functionality as "local" > with security_model=passthrough. It also chroot() into the shared > folder for extra security. But it is slower since it all requests > still go through the virtio-9p device in QEMU. This would call > for a vhost-9p implementation, but it's yet another story. > > "synth" is a software pseudo-backend, currently used to test 9pfs > with QTest (see tests/virtio-9p-test.c). Thanks for the clarification! So the proxy backend sounds like an idea that has not been implemented fully to its end. I guess it is not really used in production environments, right? What is the actual motivation for this proxy backend? And now that I look at it, I am a bit surprised that there is this pure Unix pipe socket based proxy variant, but no TCPIP network socket variant. I mean the latter is AFAIK the original idea behind the 9p protocol and IMO might be interesting to physical separate pure storage backends that way. Best regards, Christian Schoenebeck