From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f67.google.com (mail-ed1-f67.google.com [209.85.208.67]) by dpdk.org (Postfix) with ESMTP id E71924F91 for ; Tue, 30 Oct 2018 15:03:13 +0100 (CET) Received: by mail-ed1-f67.google.com with SMTP id z12-v6so4804862edp.7 for ; Tue, 30 Oct 2018 07:03:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netronome-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=gS8k7/n2Umh446zMDZ7OjNW60Iot4jCED45Gf5SJD9A=; b=gD6ic125hx1Gq38XuktGKCXR0MrJo9BQLzemOJHWfTtRBLJFGdLgXu3OghAnFyV0z0 wVrzFvRApXW4a9yLYUzECscK5O59RhX4t0b/i0fEXKQaGzf/6GAUXMuT7btZ2yq/qeiL Ykbg0UzLRWEdvsDwd3cs/CbTZ0dDfG4eoHzgtAM+YKqRJFqa9PO3G1rGbv4ToH++8xcs IDchOJV7+CzWmh+j1OrGJxqDCHys0M7qbxQ0WHNtsJHvbPxwYuBsH/s4a/jFKdoETLCr vjPIwqT3zjz1cLxq3tuBLRGKC/jGfJmNFc/Sd8rsvlJniaH3raKZeAiIr4iGy6kMd3LP 67Sg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=gS8k7/n2Umh446zMDZ7OjNW60Iot4jCED45Gf5SJD9A=; b=PhmXtcaVoyzxQkPIFryKnzy5hT7gdfunXJrPxPrVMNtkuDIyc78bGdT3DhX+7zhnFE B5qsWvOxwnIr5eLDQJdani4MtfhOftgzthqdm48/IqPXCagUhPxu+RlPu291vieXDBOF A2/TkAAhucaSu9KYLKmKw6052VxH3w63OVDHYQ6+26OfXmSjhwivX6DgE9/ubHgrnU/5 5cUFwv4NYOp7AO52xp70OJ177XZJr4/TVJNx6UETt0kDMrxlGcAHZyexNeF1UhD/exwH jtR5BXt9WxTjU2j6ljyiXCP7SrsKajf2QXr3ifyzr0aKM+iqewV7GPKieo7Qs7lF5pfk Zl3Q== X-Gm-Message-State: AGRZ1gKKg6i5I8XZVbfAIhDW51+Y/TDNyTm3Z/VGrpqmNQzSFBGq6U2N Ku7tctwiddcKWLe6KluV8zFJYa3sQNNC7keja9H7iA== X-Google-Smtp-Source: AJdET5ef8UnoSs51hE4nRfdryBKgnvJWANWus0NnMnSZjujePdTE7+zumj0oRPjnVDrmrmz66w+lt7FL1AvgosnsouY= X-Received: by 2002:a17:906:92d6:: with SMTP id d22-v6mr13064336ejx.96.1540908193372; Tue, 30 Oct 2018 07:03:13 -0700 (PDT) MIME-Version: 1.0 References: <1538599994-23331-1-git-send-email-eric.zhang@windriver.com> <3464472.yQ3oHpXKXX@xps> <1870558.97lydUBT9V@xps> In-Reply-To: From: Alejandro Lucero Date: Tue, 30 Oct 2018 14:03:02 +0000 Message-ID: To: "Burakov, Anatoly" Cc: Thomas Monjalon , eric.zhang@windriver.com, dev , "Mcnamara, John" , Allain Legacy , matt.peters@windriver.com, Stephen Hemminger , Ferruh Yigit , Andrew Rybchenko , Maxime Coquelin , Shahaf Shuler , Jerin Jacob , Hemant Agrawal , David Marchand Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Subject: Re: [dpdk-dev] [PATCH v3 0/3] force IOVA to a particular mode 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: , X-List-Received-Date: Tue, 30 Oct 2018 14:03:14 -0000 On Tue, Oct 30, 2018 at 1:48 PM Burakov, Anatoly wrote: > On 30-Oct-18 12:02 PM, Alejandro Lucero wrote: > > > > > > On Sun, Oct 28, 2018 at 11:04 PM Thomas Monjalon > > wrote: > > > > 11/10/2018 12:08, Thomas Monjalon: > > > +Cc more maintainers in order to collect more reviews > > > > > > 04/10/2018 11:19, Burakov, Anatoly: > > > > On 03-Oct-18 9:53 PM, eric zhang wrote: > > > > > This patchset introduces an EAL command line option > "--iova-mode" > > > > > to give the user a facility to force IOVA mode to a special > > value. > > > > > > > > > > Auto detection of the IOVA mode, based on probing the bus and > > IOMMU > > > > > configuration, may not report the desired addressing mode > > when virtual > > > > > devices that are not directly attached to the bus are present. > > > > > The EAL command line option "--iova-mode" can be used to > > select either > > > > > physical addressing('pa') or virtual addressing('va'). > > > > > > > > Acked-by: Anatoly Burakov > > > > > > Rebased and applied, thanks > > > > > > > > Could not this lead to a problem if a device can not wok with the mode > set? > > For example, IOVA mode set to VA and IOMMU hw with less bits than those > > required for the virtual addresses? > > > > IMO any device should be attached to a bus, and a bus should have a > > function for setting IOVA mode and the --iova-mode option just allowed > > with supported IOVA modes within the bus. > > I don't think it should work that way. It should warn the user that an > incompatible IOVA mode was selected, but the user has specified an IOVA > mode for a reason - it probably implies he really means it, so let him :) > > Yes, that's true, but setting IOVA VA when a device has problems with it, it is a bad idea and it could lead to a system crash. My concern is not with the user knowing what he is doing but with the user that "uhmm, what is this for, let's try this option". > -- > Thanks, > Anatoly >