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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E518C19F2B for ; Wed, 3 Aug 2022 23:32:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238392AbiHCXc3 (ORCPT ); Wed, 3 Aug 2022 19:32:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33106 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229881AbiHCXc1 (ORCPT ); Wed, 3 Aug 2022 19:32:27 -0400 Received: from mail-oo1-xc2c.google.com (mail-oo1-xc2c.google.com [IPv6:2607:f8b0:4864:20::c2c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 45B494E877 for ; Wed, 3 Aug 2022 16:32:26 -0700 (PDT) Received: by mail-oo1-xc2c.google.com with SMTP id d12-20020a4aeb8c000000b004214e709b72so3261484ooj.6 for ; Wed, 03 Aug 2022 16:32:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fooishbar-org.20210112.gappssmtp.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc; bh=ZZp/mpqWm7MHvgF6uTyDMp42kr2Njy7C2uXF4wQPOwo=; b=3DPS0mjfbJdbjToepDdO1S2S3zdUjdQJBt0jGkacyWBVxaE/Tsg0FESZtVHQG6E6S3 U2kREMlA1P3Bf8hZ4/RhW0vfQk5neJMTiIUpL16lZ7KjxduKAKuN3r5vZwVl0FGlI5O7 wcVGwQvcYLayLWi3fMxucb6Hmj+Vqv8lPACXPSnYWMIknnB1Hh0EwqGw/EDWLqeQ6kLB 4P17IjI6LKt+S+hAlywSHRWBBvzdJZQ8o0S38u/fuA+EHcgdD7AIfKu4i3rzMBaQ9Vgz 1RgX/yCkO2EsHnfXzDw5yLrXZce71rZmnVmtW6ELxu6KhU2gvBfakCEklhz69027+yqp qZ1g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc; bh=ZZp/mpqWm7MHvgF6uTyDMp42kr2Njy7C2uXF4wQPOwo=; b=PGUs+bHHrq3NN/uFbcP4Jf4j0/UpnhLTQnH5HHLDzmlIqcsbHLpZK3YGt2t2ixvEcR /8n653hLeAIhHPlzTO+rGTJD7oLPW01gMSlmuy8yvlIg64VXTZGKW5snElF0xgD1aAJT LGQXjEsJOYXgZkOoGJXgVzwUMxmQBvUtoBPUnoVp/3aJ1yh8P07OIHZu41f7ssCAo2uQ WpFIk1bh/pCmuq+YKl/E4vC/97sIUcBWBv/c5FzSimyxg2C8EShETCI1AqpdQltFutap 4p3t8xoZxEyHLwvbsHaDEbx3nJ581BjlwNi6YNYrf7IT19cLR6tncWiM/jBs2dZPe+fK HVIw== X-Gm-Message-State: AJIora/Ni3Zwzhv2PmQgKKBb+xTs01XtzOI7TX8NpA06hbZ5HBYkWNGQ mWRnI9a3SxzY1CtzcMwLDSedy11qQ7Xf7u+QIjW9iVhhii4EWg== X-Google-Smtp-Source: AGRyM1sHmMNEUlUl3pAbbNlUgZITxMc87KTUVrIRloEeKvKXACYdDy9c7oiQXFxRG56P/md1h2R0fVXfJVHLpnBXJuo= X-Received: by 2002:a4a:95ca:0:b0:435:fcc6:5eca with SMTP id p10-20020a4a95ca000000b00435fcc65ecamr8893903ooi.5.1659569545598; Wed, 03 Aug 2022 16:32:25 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Daniel Stone Date: Thu, 4 Aug 2022 00:31:16 +0100 Message-ID: Subject: Re: New subsystem for acceleration devices To: Oded Gabbay Cc: Dave Airlie , Greg Kroah-Hartman , Yuji Ishikawa , Jiho Chu , Arnd Bergmann , "Linux-Kernel@Vger. Kernel. Org" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Oded, On Wed, 3 Aug 2022 at 21:21, Oded Gabbay wrote: > The reason it happened now is because I saw two drivers, which are > doing h/w acceleration for AI, trying to be accepted to the misc > subsystem. Why misc? > Regarding the open source userspace rules in drm - yes, I think your > rules are too limiting for the relatively young AI scene, and I saw at > the 2021 kernel summit that other people from the kernel community > think that as well. > But that's not the main reason, or even a reason at all for doing > this. After all, at least for habana, we open-sourced our compiler and > a runtime library. And Greg also asked those two drivers if they have > matching open-sourced user-space code. > > And a final reason is that I thought this can also help in somewhat > reducing the workload on Greg. I saw in the last kernel summit there > was a concern about bringing more people to be kernel maintainers so I > thought this is a step in the right direction. Can you please explain what the reason is here? Everything you have described - uniform device enumeration, common job description, memory management helpers, unique job submission format, etc - applies exactly to DRM. If open userspace is not a requirement, and bypassing Greg's manual merging is a requirement, then I don't see what the difference is between DRM and this new bespoke subsystem. It would be great to have these differences enumerated in email as well as in kerneldoc. Cheers, Daniel