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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 C9685C31E40 for ; Sat, 10 Aug 2019 00:48:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8B9EA2166E for ; Sat, 10 Aug 2019 00:48:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565398119; bh=8knKnN5NvOEmPnMLcZSF8WYpy6HGhXAHy4YEOjEoWqA=; h=Subject:To:Cc:References:From:Date:In-Reply-To:List-ID:From; b=OBp/rCrR5afL8vRG4/huMK/Ckc0nA9F/ndbvO6K1POcxxH0Dw6I4rGPZ/nOu9W84g ijLhXq0zJkvSoVqleECT11/oLETueHt1IUF6CcisKfmkkGb8qDVd0gOpWRS0lIP+ZJ cBPkEiUXv18olp1pAj7h1QyE+68QC7XqvF1h/kVU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726865AbfHJAsg (ORCPT ); Fri, 9 Aug 2019 20:48:36 -0400 Received: from mail-ot1-f68.google.com ([209.85.210.68]:39444 "EHLO mail-ot1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726137AbfHJAsf (ORCPT ); Fri, 9 Aug 2019 20:48:35 -0400 Received: by mail-ot1-f68.google.com with SMTP id r21so133476888otq.6 for ; Fri, 09 Aug 2019 17:48:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=google; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=WebZ25TRZtkhIa50lHla/qWQXpBkJ9sflP4Hbz+vD+Y=; b=HuvBXVEeCNJWw84wz2l726tE2rPCX5b7UhwTqnMzb+iFWOIISsomNj5hTBeUAArs6w ITfd8inpKFZDKwzvk1EseKDSy/vZpWS0eHB+GHYdBDb96BuhJhczv9qUfKF9C9WMXWw7 065nUqfWjU48xMlevxVY3Ah9SOSSwUzJ/S8HI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=WebZ25TRZtkhIa50lHla/qWQXpBkJ9sflP4Hbz+vD+Y=; b=U9i2OSI9lCJnJ7LKvifr0FL2n/yC9q7A7AKNhWNwwP37FtpMCXV8MiPK/Bqf1ePhc/ vcooBXnBUf9ykBxcu4Q8r7qhPWIbj+K2Er8FkHWMLXKUyFzEDH8/2S/2MPXrcsnoCr9b KJfw9ZnuM756s0tn5aWYna3CWeCukoPlEzVOmPBMHnFkLrmOnFPzlkvzeqNS9TBfHeLu 3em1RBuuHBlje/IFtqCA4RJupaaS6IUS0D7hkeIVylEcbQdouabeHwC5bwMLdAIJAbT+ N8qIJItbuZxW62vtWZtZdOk6uOyJw6UOI6slQbQBkpEahkZisYsqvst3v4CfrFfz3It6 kBXg== X-Gm-Message-State: APjAAAVuLDJ2uUYFEiswnKzxLVshp9hWrrgI98PvQ/gt2JHdMahK4Rcn 9jNFBwOEIPYeUlH9ufaSJ7kd1A== X-Google-Smtp-Source: APXvYqxDK6ADZuMJjzYO20j/ly4fmcARa1eZmgkezIM1D1cjRzbn+HSuwH5lcb+MB3iNlDBLSkcOlw== X-Received: by 2002:a6b:ce19:: with SMTP id p25mr9257284iob.201.1565398114400; Fri, 09 Aug 2019 17:48:34 -0700 (PDT) Received: from [192.168.1.112] (c-24-9-64-241.hsd1.co.comcast.net. [24.9.64.241]) by smtp.gmail.com with ESMTPSA id w5sm6219382iom.33.2019.08.09.17.48.33 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 09 Aug 2019 17:48:33 -0700 (PDT) Subject: Re: [PATCH 0/3] Collapse vimc into single monolithic driver To: =?UTF-8?Q?Andr=c3=a9_Almeida?= , mchehab@kernel.org, helen.koike@collabora.com, hverkuil@xs4all.nl, laurent.pinchart@ideasonboard.com Cc: linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, kernel@collabora.com, "skh >> Shuah Khan" References: <3118bc46-14ac-8015-9a6c-a8dfcdcea940@collabora.com> <4e9b8eb3-23c5-62ea-07dc-b51acb238dee@linuxfoundation.org> <15badf5e-49fa-7fbe-de6b-296e9a7f5cd9@collabora.com> From: Shuah Khan Message-ID: Date: Fri, 9 Aug 2019 18:48:32 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <15badf5e-49fa-7fbe-de6b-296e9a7f5cd9@collabora.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On 8/9/19 6:24 PM, André Almeida wrote: > On 8/9/19 9:17 PM, Shuah Khan wrote: >> Hi Andre, >> >> On 8/9/19 5:52 PM, André Almeida wrote: >>> Hello Shuah, >>> >>> Thanks for the patch, I did some comments below. >>> >>> On 8/9/19 6:45 PM, Shuah Khan wrote: >>>> vimc uses Component API to split the driver into functional components. >>>> The real hardware resembles a monolith structure than component and >>>> component structure added a level of complexity making it hard to >>>> maintain without adding any real benefit. >>>>      The sensor is one vimc component that would makes sense to be a >>>> separate >>>> module to closely align with the real hardware. It would be easier to >>>> collapse vimc into single monolithic driver first and then split the >>>> sensor off as a separate module. >>>> >>>> This patch series emoves the component API and makes minimal changes to >>>> the code base preserving the functional division of the code structure. >>>> Preserving the functional structure allows us to split the sensor off >>>> as a separate module in the future. >>>> >>>> Major design elements in this change are: >>>>      - Use existing struct vimc_ent_config and struct >>>> vimc_pipeline_config >>>>        to drive the initialization of the functional components. >>>>      - Make vimc_ent_config global by moving it to vimc.h >>>>      - Add two new hooks add and rm to initialize and register, >>>> unregister >>>>        and free subdevs. >>>>      - All component API is now gone and bind and unbind hooks are >>>> modified >>>>        to do "add" and "rm" with minimal changes to just add and rm >>>> subdevs. >>>>      - vimc-core's bind and unbind are now register and unregister. >>>>      - vimc-core invokes "add" hooks from its vimc_register_devices(). >>>>        The "add" hooks remain the same and register subdevs. They don't >>>>        create platform devices of their own and use vimc's pdev.dev as >>>>        their reference device. The "add" hooks save their >>>> vimc_ent_device(s) >>>>        in the corresponding vimc_ent_config. >>>>      - vimc-core invokes "rm" hooks from its unregister to unregister >>>> subdevs >>>>        and cleanup. >>>>      - vimc-core invokes "add" and "rm" hooks with pointer to struct >>>> vimc_device >>>>        and the corresponding struct vimc_ent_config pointer. >>>>      The following configure and stream test works on all devices. >>>>           media-ctl -d platform:vimc -V '"Sensor >>>> A":0[fmt:SBGGR8_1X8/640x480]' >>>>      media-ctl -d platform:vimc -V '"Debayer >>>> A":0[fmt:SBGGR8_1X8/640x480]' >>>>      media-ctl -d platform:vimc -V '"Sensor >>>> B":0[fmt:SBGGR8_1X8/640x480]' >>>>      media-ctl -d platform:vimc -V '"Debayer >>>> B":0[fmt:SBGGR8_1X8/640x480]' >>>>           v4l2-ctl -z platform:vimc -d "RGB/YUV Capture" -v >>>> width=1920,height=1440 >>>>      v4l2-ctl -z platform:vimc -d "Raw Capture 0" -v pixelformat=BA81 >>>>      v4l2-ctl -z platform:vimc -d "Raw Capture 1" -v pixelformat=BA81 >>>>           v4l2-ctl --stream-mmap --stream-count=100 -d /dev/video1 >>>>      v4l2-ctl --stream-mmap --stream-count=100 -d /dev/video2 >>>>      v4l2-ctl --stream-mmap --stream-count=100 -d /dev/video3 >>>> >>>> The third patch in the series fixes a general protection fault found >>>> when rmmod is done while stream is active. >>> >>> I applied your patch on top of media_tree/master and I did some testing. >>> Not sure if I did something wrong, but just adding and removing the >>> module generated a kernel panic: >> >> Thanks for testing. >> >> Odd. I tested modprobe and rmmod both.I was working on Linux 5.3-rc2. >> I will apply these to media latest and work from there. I have to >> rebase these on top of the reverts from Lucas and Helen > > Ok, please let me know if I succeeded to reproduce. > >>> >>> ~# modprobe vimc >>> ~# rmmod vimc >>> [   16.452974] stack segment: 0000 [#1] SMP PTI >>> [   16.453688] CPU: 0 PID: 2038 Comm: rmmod Not tainted 5.3.0-rc2+ #36 >>> [   16.454678] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), >>> BIOS 1.12.0-20181126_142135-anatol 04/01/2014 >>> [   16.456191] RIP: 0010:kfree+0x4d/0x240 >>> >>> >>> >>> [   16.469188] Call Trace: >>> [   16.469666]  vimc_remove+0x35/0x90 [vimc] >>> [   16.470436]  platform_drv_remove+0x1f/0x40 >>> [   16.471233]  device_release_driver_internal+0xd3/0x1b0 >>> [   16.472184]  driver_detach+0x37/0x6b >>> [   16.472882]  bus_remove_driver+0x50/0xc1 >>> [   16.473569]  vimc_exit+0xc/0xca0 [vimc] >>> [   16.474231]  __x64_sys_delete_module+0x18d/0x240 >>> [   16.475036]  do_syscall_64+0x43/0x110 >>> [   16.475656]  entry_SYSCALL_64_after_hwframe+0x44/0xa9 >>> [   16.476504] RIP: 0033:0x7fceb8dafa4b >>> >>> >>> >>> [   16.484853] Modules linked in: vimc(-) videobuf2_vmalloc >>> videobuf2_memops v4l2_tpg videobuf2_v4l2 videobuf2_common >>> [   16.486187] ---[ end trace 91e5e0894e254d49 ]--- >>> [   16.486758] RIP: 0010:kfree+0x4d/0x240 >>> >>> >>> >>> fish: “rmmod vimc” terminated by signal SIGSEGV (Address boundary error) >>> >>> I just added the module after booting, no other action was made. Here is >>> how my `git log --oneline` looks like: >>> >>> 897d708e922b media: vimc: Fix gpf in rmmod path when stream is active >>> 2e4a5ad8ad6d media: vimc: Collapse component structure into a single >>> monolithic driver >>> 7c8da1687e92 media: vimc: move private defines to a common header >>> 97299a303532 media: Remove dev_err() usage after platform_get_irq() >>> 25a3d6bac6b9 media: adv7511/cobalt: rename driver name to adv7511-v4l2 >>> ... >>> >>>> >>>> vimc_print_dot (--print-dot) topology after this change: >>>> digraph board { >>>>     rankdir=TB >>>>     n00000001 [label="{{} | Sensor A\n/dev/v4l-subdev0 | { >>>> 0}}", shape=Mrecord, style=filled, fillcolor=green] >>>>     n00000001:port0 -> n00000005:port0 [style=bold] >>>>     n00000001:port0 -> n0000000b [style=bold] >>>>     n00000003 [label="{{} | Sensor B\n/dev/v4l-subdev1 | { >>>> 0}}", shape=Mrecord, style=filled, fillcolor=green] >>>>     n00000003:port0 -> n00000008:port0 [style=bold] >>>>     n00000003:port0 -> n0000000f [style=bold] >>>>     n00000005 [label="{{ 0} | Debayer A\n/dev/v4l-subdev2 | >>>> { 1}}", shape=Mrecord, style=filled, fillcolor=green] >>>>     n00000005:port1 -> n00000015:port0 >>>>     n00000008 [label="{{ 0} | Debayer B\n/dev/v4l-subdev3 | >>>> { 1}}", shape=Mrecord, style=filled, fillcolor=green] >>>>     n00000008:port1 -> n00000015:port0 [style=dashed] >>>>     n0000000b [label="Raw Capture 0\n/dev/video1", shape=box, >>>> style=filled, fillcolor=yellow] >>>>     n0000000f [label="Raw Capture 1\n/dev/video2", shape=box, >>>> style=filled, fillcolor=yellow] >>>>     n00000013 [label="{{} | RGB/YUV Input\n/dev/v4l-subdev4 | >>>> { 0}}", shape=Mrecord, style=filled, fillcolor=green] >>>>     n00000013:port0 -> n00000015:port0 [style=dashed] >>>>     n00000015 [label="{{ 0} | Scaler\n/dev/v4l-subdev5 | >>>> { 1}}", shape=Mrecord, style=filled, fillcolor=green] >>>>     n00000015:port1 -> n00000018 [style=bold] >>>>     n00000018 [label="RGB/YUV Capture\n/dev/video3", shape=box, >>>> style=filled, fillcolor=yellow] >>>> } >>> >>> Since the topology changed, it would be nice to change in the >>> documentation as well. The current dot file can be found at >>> `Documentation/media/v4l-drivers/vimc.dot` and it's rendered at this >>> page: https://www.kernel.org/doc/html/latest/media/v4l-drivers/vimc.html >>> >> >> Topology shouldn't have changed. No changes to links or pads etc. >> I will take a look to be sure. I agree that if topology changes >> document should be updated. > > If you "diff" the current dot with the dot you generated, you will see > some differences. The main difference is that "RGB/YUV Input" was a > device "/dev/video2/", and now it a subdevice "/dev/v4l-subdev4". > Yeah. I should have saved dot before my changes and compare. The goal is to not change anything. I will make sure topology doesn't change. Thanks again for testing these patches quickly. thanks, -- Shuah