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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 D514FC433ED for ; Thu, 13 May 2021 12:01:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B40AD61435 for ; Thu, 13 May 2021 12:01:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233212AbhEMMCN (ORCPT ); Thu, 13 May 2021 08:02:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38452 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233061AbhEMMCK (ORCPT ); Thu, 13 May 2021 08:02:10 -0400 Received: from mail-qk1-x730.google.com (mail-qk1-x730.google.com [IPv6:2607:f8b0:4864:20::730]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1AB9BC061574 for ; Thu, 13 May 2021 05:01:01 -0700 (PDT) Received: by mail-qk1-x730.google.com with SMTP id o27so25154363qkj.9 for ; Thu, 13 May 2021 05:01:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=NJihL2Xw2lHhkxSxjm+gjn8CDqqOTmpq6YLn31gRVlo=; b=M8TgruUqCLhDzSxpaZE6ZcHOf7qpdfRsiP60D15PaB+xgLxnWTKx++sLGfwnuEY7cK uTYSf6cnwrBxnDipK3mbByMUjNzCtv1L/Oc0MBJlorr4NuoxvcGkikJ5BmLG8fbvE38K cwW6Vm2DWhlAD6Eowz2NJT8cl5tk+WTOTtU+xd01yaVbd5ckZ576ptV9N5Xs3i+gxPAw 2lJz5jv2tvdGhWn/ak1dF0461aZaFpTVHnvAOx9H2sx1wXa9fA05Uxpg9Bwu5ECS9aek C6gecVqVy/zLo76dzPwDBYJVfNzm4wyZXebHd+I7rH6wm0Ah7oP8HeQv9jNhbqP1eekf KNGA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=NJihL2Xw2lHhkxSxjm+gjn8CDqqOTmpq6YLn31gRVlo=; b=HqlS4h25kf0FI9J1uS0iFSsev5OWvdBfGhCIZb9KCibtpxNsj15LqsqnPXAi6HSNbr Yo4wBcc9g/HUgj6FVz4s5HwLqdQ1ij1cunkeGMExd8CIOQWb7SPwR09jGZAKTzpXZIMR XFuccbhbavW//lZ8UnFD4gV3PV/Pyw2/Fg486RZ8GQ7HGAnnCPE40cBI/HlMF3I7n7Kh iJN3pOeButB7zHjnqdevDwZ7ZPNgHH7JwYlU0XJDbDqY5qHjyYtOPbNutc0ROW+8mqy/ xrJm8WhRCU3++hy1cDJgzmrStPurjpJdZEfBN3lSz5iXo0u5G2A6VzuMui/LAxpAckqO yJ+Q== X-Gm-Message-State: AOAM530vVN3N8SmW91l4BkcTlphGY59hdmJFcJsXyaWTa9R8/wTTd4cZ z3MIRfNR5JmbbqnGzN7vO6tFag== X-Google-Smtp-Source: ABdhPJwdEODv0dV1RGQbKjSCOgnSJl/y5fEW7JnLEVOJ+y3Rq/nxRWKcs8mWpepP6QF3X0y4yh8XwQ== X-Received: by 2002:a37:a301:: with SMTP id m1mr38481585qke.491.1620907260254; Thu, 13 May 2021 05:01:00 -0700 (PDT) Received: from ziepe.ca (hlfxns017vw-47-55-113-94.dhcp-dynamic.fibreop.ns.bellaliant.net. [47.55.113.94]) by smtp.gmail.com with ESMTPSA id b188sm2207623qkc.11.2021.05.13.05.00.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 13 May 2021 05:00:59 -0700 (PDT) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1lhA1S-006ntk-K6; Thu, 13 May 2021 09:00:58 -0300 Date: Thu, 13 May 2021 09:00:58 -0300 From: Jason Gunthorpe To: "Tian, Kevin" Cc: Christoph Hellwig , Joerg Roedel , Alex Williamson , David Woodhouse , Lu Baolu , Will Deacon , Kirti Wankhede , "linux-arm-kernel@lists.infradead.org" , "iommu@lists.linux-foundation.org" , "kvm@vger.kernel.org" Subject: Re: [PATCH 3/6] vfio: remove the unused mdev iommu hook Message-ID: <20210513120058.GG1096940@ziepe.ca> References: <20210510065405.2334771-1-hch@lst.de> <20210510065405.2334771-4-hch@lst.de> <20210510155454.GA1096940@ziepe.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, May 13, 2021 at 03:28:52AM +0000, Tian, Kevin wrote: > Are you specially concerned about this iommu_device hack which > directly connects mdev_device to iommu layer or the entire removed > logic including the aux domain concept? For the former we are now > following up the referred thread to find a clean way. But for the latter > we feel it's still necessary regardless of how iommu interface is redesigned > to support device connection from the upper level driver. The reason is > that with mdev or subdevice one physical device could be attached to > multiple domains now. there could be a primary domain with DOMAIN_ > DMA type for DMA_API use by parent driver itself, and multiple auxiliary > domains with DOMAIN_UNMANAGED types for subdevices assigned to > different VMs. Why do we need more domains than just the physical domain for the parent? How does auxdomain appear in /dev/ioasid? I never understood what this dead code was supposed to be used for. Jason