From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 7F57BA00E6 for ; Tue, 9 Jul 2019 17:04:32 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 2454D1B95C; Tue, 9 Jul 2019 17:04:32 +0200 (CEST) Received: from wout5-smtp.messagingengine.com (wout5-smtp.messagingengine.com [64.147.123.21]) by dpdk.org (Postfix) with ESMTP id 8B11C1B959 for ; Tue, 9 Jul 2019 17:04:30 +0200 (CEST) Received: from compute1.internal (compute1.nyi.internal [10.202.2.41]) by mailout.west.internal (Postfix) with ESMTP id DAE0E46F; Tue, 9 Jul 2019 11:04:28 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute1.internal (MEProxy); Tue, 09 Jul 2019 11:04:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=monjalon.net; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s=mesmtp; bh=o/PYiZRDuMp1iYz6BvmQSiPcAApx3WCYi7LVI5dq9vs=; b=J3z65+VFHbH5 ACUVbGRDjG9lXHLJUmsdm/InA0HijaJgYCvAcuIBapkr+Sto3z29x8ffr6w3DV0P CvKY9njTAKgmDPKt/H+fFsTC5OLx615jmsu7hVDSZ9/Svz2lS69SsZes4yyZmgqm m3JxGwG8S7A/bP6rjE8HFmBrjEXaqd0= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm3; bh=o/PYiZRDuMp1iYz6BvmQSiPcAApx3WCYi7LVI5dq9 vs=; b=A57KLQhXsp1tASGhMxZ+VnwJ10M0KntPLM52OL3OBWh3nN6apbMfydfi7 RCdftryJk2C55AFMBuCskDYOzGdGvxu6RLb5YkYL7g4Q1GJqjCKa2piNJ/BrQMs+ SD2JGtFcAg8HsJnyt3I5wI6BWCIaz/55yjwjFTr+ZnDYJ/Zp1mu5qNaJTIQtagvn IezxEM3utaTVJuKvGyqr4pnyP0CWyV7krED8Wh05El/GZMf/IyDCTgUPG7SeQftb mQNLNMWh0FiF2SyOAbPneRtwa4RxX/laEOBdEC1KXIl77kkMIze/felJTdOH+JkR L6Ys/Ke5aoJQER0UfUIjWiRXuHJKQ== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduvddrgedvgdekjecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefhvffufffkjghfggfgtgesthfuredttddtvdenucfhrhhomhepvfhhohhmrghs ucfoohhnjhgrlhhonhcuoehthhhomhgrshesmhhonhhjrghlohhnrdhnvghtqeenucfkph epjeejrddufeegrddvtdefrddukeegnecurfgrrhgrmhepmhgrihhlfhhrohhmpehthhho mhgrshesmhhonhhjrghlohhnrdhnvghtnecuvehluhhsthgvrhfuihiivgeptd X-ME-Proxy: Received: from xps.localnet (184.203.134.77.rev.sfr.net [77.134.203.184]) by mail.messagingengine.com (Postfix) with ESMTPA id F3CFB80060; Tue, 9 Jul 2019 11:04:25 -0400 (EDT) From: Thomas Monjalon To: "Burakov, Anatoly" , Jerin Jacob Kollanukkaran , David Marchand Cc: dev , Ben Walker Date: Tue, 09 Jul 2019 17:04:23 +0200 Message-ID: <2073381.Trv6OtLvPF@xps> In-Reply-To: <553b3a91-7458-98d0-9df6-5b53010d326f@intel.com> References: <20190708142450.51597-1-jerinj@marvell.com> <553b3a91-7458-98d0-9df6-5b53010d326f@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Subject: Re: [dpdk-dev] [EXT] Re: [PATCH] bus/pci: fix IOVA as VA mode selection X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 09/07/2019 16:37, Burakov, Anatoly: > My view would be to always run in IOVA as VA by default and only falling > back to IOVA as PA if there is a need to do that. Yet, it seems that > whenever i try to bring this up, the response (not necessarily from you, > so this is not directed at you specifically) seems to be that because of > hotplug, we have to start in the "safest" (from device support point of > view) mode - that is, in IOVA as PA. Seeing how, as you claim, some > devices require IOVA as VA, then IOVA as PA is no longer the "safe" > default that all devices will support. Perhaps we can use this > opportunity to finally make IOVA as VA the default :) That's a good point Anatoly. We need to decide what is the safest default. About the capabilities flags, please let's agree that we want to express 3 cases, so we need 2 flags. About the preference of a mode for a device, if a mode is really bad for a device, I suggest to not advertise it in capabilities. In order to take a better decision, we need a summary of the decision algorithm per layer, involving kernel driver capabilities and memory capabilities.