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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0A8B8C28B23 for ; Wed, 5 Mar 2025 13:14:48 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tpoZK-0004tw-Pn; Wed, 05 Mar 2025 08:13:50 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tpoZH-0004tc-D3 for qemu-devel@nongnu.org; Wed, 05 Mar 2025 08:13:48 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tpoZF-00012Q-CG for qemu-devel@nongnu.org; Wed, 05 Mar 2025 08:13:46 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1741180423; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=w82E2Dy64YVsrOg8XgWKYMUp0K7NFjHu1Ck/pMvu8es=; b=HsFhCUVWtRXIt1KZd5O7dobasqHojC+W04dF6uYeekieZs7XzuIUyfMDZgev2dQ6mycwIK 1O+rXVFIQn2Bqdvm1HKjwI9wbdNNY19C7CPF4gtLd5Ih3l2Px7ZrD/oPMlk0g/RjyeES6M 3auA8AjyZwIAPTg0sn07uWiZD2YVFAQ= Received: from mail-wr1-f70.google.com (mail-wr1-f70.google.com [209.85.221.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-546-hOV5aktLN46PvuFL7pLe8A-1; Wed, 05 Mar 2025 08:13:41 -0500 X-MC-Unique: hOV5aktLN46PvuFL7pLe8A-1 X-Mimecast-MFC-AGG-ID: hOV5aktLN46PvuFL7pLe8A_1741180420 Received: by mail-wr1-f70.google.com with SMTP id ffacd0b85a97d-390de58dc4eso6345214f8f.0 for ; Wed, 05 Mar 2025 05:13:41 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1741180420; x=1741785220; h=content-transfer-encoding:in-reply-to:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=w82E2Dy64YVsrOg8XgWKYMUp0K7NFjHu1Ck/pMvu8es=; b=NcxS0h7qLmb9X3As78ISb/iURo0QMOm7GVtWom2kHPhSzY8f9+OE5xSa9fDT6FcepU xQtUGxd7JqyPhvYc/n5kyrzNsp5HobGNiTXQEA0Wutdrv/Wy72j2s4DWbNsUVG5clNwJ YS5vuXC6w3dwe7KW941T2qIsuRvmoAXoaqe2wtVheQJO8hhad/SITyC5KgYoGN9zmR+P cp7j6bNvB2XHsQ6hWBq77N9ezO+vY7AkonLY37LXFcATLfxtsc3reAP/JLkz3kMhelD7 9zDPLkNBSDe8YrpRcSrgyWaSODDBk3jt7wYup4WsMmhDRNx38FZbpi9uSzpvkNS/ZCs0 g51A== X-Gm-Message-State: AOJu0YwfwfyOWVTEXIr5O73I+Xw2C8MvYHqGxlyMsJRDrMoM+/Ulzqp9 WgIxPC8/y+9JeBvGb1QSbZ9NCYYdmHxfXN7fLECCbc93QQvOYi+6hMNcPSemOB4SdILvgXdEmmf lncFuynenS5iDMq+Ld0wNlW55dBB+DcYLT7QktZ1Dnpm+FC2WfhS3 X-Gm-Gg: ASbGncv2WerRjBISZ+KxSI2S4lYpRf08sgGR+gyVV4NqvL8jIqxCsi3GpPnALuoWAK4 PQ2VQSwdtVh90C5ARp9UmESXCeU4CAjU+jegQUHtrZP+TXkygtVE0+UF8Bhz4KGjbSzdRFnUvAY +nGwP8I4JH3lHvjbui4zRnZyXTXamAjCTV8psqxM+4w5QY0gBLUltlNWIA7VY2G/fWmVhUw+KcA 8ciAP+pbUUmytQAm78cvTcuA3sHKPu6anRLFfmSgwGboHWEMy1olnMY9lQawOJ7WbvMDpZKGMVI H3awvkvFK9KfNMUaUvbVF+ahEv5yYRywxHxnC1fj9C7+xyi762ENyQ== X-Received: by 2002:a05:6000:2a86:b0:391:253b:4050 with SMTP id ffacd0b85a97d-391253b435amr1249284f8f.51.1741180420325; Wed, 05 Mar 2025 05:13:40 -0800 (PST) X-Google-Smtp-Source: AGHT+IEAZBDcEernJgvo0xHlPG48Zu4kmVfY797BGlFwWYNmwvAYaHfLSgwPRfJVumvTPvyl8YqCTw== X-Received: by 2002:a05:6000:2a86:b0:391:253b:4050 with SMTP id ffacd0b85a97d-391253b435amr1249251f8f.51.1741180419941; Wed, 05 Mar 2025 05:13:39 -0800 (PST) Received: from ?IPV6:2a01:e0a:280:24f0:9db0:474c:ff43:9f5c? ([2a01:e0a:280:24f0:9db0:474c:ff43:9f5c]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-390e47b6ddesm20939950f8f.41.2025.03.05.05.13.39 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 05 Mar 2025 05:13:39 -0800 (PST) Message-ID: <8ac4f034-3e68-4c8a-9a63-9eeacc0de113@redhat.com> Date: Wed, 5 Mar 2025 14:13:38 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] vfio: Add property documentation To: Joao Martins , Alex Williamson , Kirti Wankhede Cc: qemu-devel@nongnu.org, Tony Krowiak , Eric Farman , Eric Auger , tomitamoeko@gmail.com, corvin.koehne@gmail.com References: <20250213135050.1426258-1-clg@redhat.com> <20250213144513.32b3241f.alex.williamson@redhat.com> <995ef2ed-a5e0-469e-b780-6800f26d7b22@redhat.com> <6985a62f-a091-4087-887c-361570170ef6@oracle.com> Content-Language: en-US, fr From: =?UTF-8?Q?C=C3=A9dric_Le_Goater?= Autocrypt: addr=clg@redhat.com; keydata= xsFNBFu8o3UBEADP+oJVJaWm5vzZa/iLgpBAuzxSmNYhURZH+guITvSySk30YWfLYGBWQgeo 8NzNXBY3cH7JX3/a0jzmhDc0U61qFxVgrPqs1PQOjp7yRSFuDAnjtRqNvWkvlnRWLFq4+U5t yzYe4SFMjFb6Oc0xkQmaK2flmiJNnnxPttYwKBPd98WfXMmjwAv7QfwW+OL3VlTPADgzkcqj 53bfZ4VblAQrq6Ctbtu7JuUGAxSIL3XqeQlAwwLTfFGrmpY7MroE7n9Rl+hy/kuIrb/TO8n0 ZxYXvvhT7OmRKvbYuc5Jze6o7op/bJHlufY+AquYQ4dPxjPPVUT/DLiUYJ3oVBWFYNbzfOrV RxEwNuRbycttMiZWxgflsQoHF06q/2l4ttS3zsV4TDZudMq0TbCH/uJFPFsbHUN91qwwaN/+ gy1j7o6aWMz+Ib3O9dK2M/j/O/Ube95mdCqN4N/uSnDlca3YDEWrV9jO1mUS/ndOkjxa34ia 70FjwiSQAsyIwqbRO3CGmiOJqDa9qNvd2TJgAaS2WCw/TlBALjVQ7AyoPEoBPj31K74Wc4GS Rm+FSch32ei61yFu6ACdZ12i5Edt+To+hkElzjt6db/UgRUeKfzlMB7PodK7o8NBD8outJGS tsL2GRX24QvvBuusJdMiLGpNz3uqyqwzC5w0Fd34E6G94806fwARAQABzSJDw6lkcmljIExl IEdvYXRlciA8Y2xnQHJlZGhhdC5jb20+wsGRBBMBCAA7FiEEoPZlSPBIlev+awtgUaNDx8/7 7KEFAmTLlVECGwMFCwkIBwICIgIGFQoJCAsCBBYCAwECHgcCF4AACgkQUaNDx8/77KG0eg// S0zIzTcxkrwJ/9XgdcvVTnXLVF9V4/tZPfB7sCp8rpDCEseU6O0TkOVFoGWM39sEMiQBSvyY lHrP7p7E/JYQNNLh441MfaX8RJ5Ul3btluLapm8oHp/vbHKV2IhLcpNCfAqaQKdfk8yazYhh EdxTBlzxPcu+78uE5fF4wusmtutK0JG0sAgq0mHFZX7qKG6LIbdLdaQalZ8CCFMKUhLptW71 xe+aNrn7hScBoOj2kTDRgf9CE7svmjGToJzUxgeh9mIkxAxTu7XU+8lmL28j2L5uNuDOq9vl hM30OT+pfHmyPLtLK8+GXfFDxjea5hZLF+2yolE/ATQFt9AmOmXC+YayrcO2ZvdnKExZS1o8 VUKpZgRnkwMUUReaF/mTauRQGLuS4lDcI4DrARPyLGNbvYlpmJWnGRWCDguQ/LBPpbG7djoy k3NlvoeA757c4DgCzggViqLm0Bae320qEc6z9o0X0ePqSU2f7vcuWN49Uhox5kM5L86DzjEQ RHXndoJkeL8LmHx8DM+kx4aZt0zVfCHwmKTkSTQoAQakLpLte7tWXIio9ZKhUGPv/eHxXEoS 0rOOAZ6np1U/xNR82QbF9qr9TrTVI3GtVe7Vxmff+qoSAxJiZQCo5kt0YlWwti2fFI4xvkOi V7lyhOA3+/3oRKpZYQ86Frlo61HU3r6d9wzOwU0EW7yjdQEQALyDNNMw/08/fsyWEWjfqVhW pOOrX2h+z4q0lOHkjxi/FRIRLfXeZjFfNQNLSoL8j1y2rQOs1j1g+NV3K5hrZYYcMs0xhmrZ KXAHjjDx7FW3sG3jcGjFW5Xk4olTrZwFsZVUcP8XZlArLmkAX3UyrrXEWPSBJCXxDIW1hzwp bV/nVbo/K9XBptT/wPd+RPiOTIIRptjypGY+S23HYBDND3mtfTz/uY0Jytaio9GETj+fFis6 TxFjjbZNUxKpwftu/4RimZ7qL+uM1rG1lLWc9SPtFxRQ8uLvLOUFB1AqHixBcx7LIXSKZEFU CSLB2AE4wXQkJbApye48qnZ09zc929df5gU6hjgqV9Gk1rIfHxvTsYltA1jWalySEScmr0iS YBZjw8Nbd7SxeomAxzBv2l1Fk8fPzR7M616dtb3Z3HLjyvwAwxtfGD7VnvINPbzyibbe9c6g LxYCr23c2Ry0UfFXh6UKD83d5ybqnXrEJ5n/t1+TLGCYGzF2erVYGkQrReJe8Mld3iGVldB7 JhuAU1+d88NS3aBpNF6TbGXqlXGF6Yua6n1cOY2Yb4lO/mDKgjXd3aviqlwVlodC8AwI0Sdu jWryzL5/AGEU2sIDQCHuv1QgzmKwhE58d475KdVX/3Vt5I9kTXpvEpfW18TjlFkdHGESM/Jx IqVsqvhAJkalABEBAAHCwV8EGAECAAkFAlu8o3UCGwwACgkQUaNDx8/77KEhwg//WqVopd5k 8hQb9VVdk6RQOCTfo6wHhEqgjbXQGlaxKHoXywEQBi8eULbeMQf5l4+tHJWBxswQ93IHBQjK yKyNr4FXseUI5O20XVNYDJZUrhA4yn0e/Af0IX25d94HXQ5sMTWr1qlSK6Zu79lbH3R57w9j hQm9emQEp785ui3A5U2Lqp6nWYWXz0eUZ0Tad2zC71Gg9VazU9MXyWn749s0nXbVLcLS0yop s302Gf3ZmtgfXTX/W+M25hiVRRKCH88yr6it+OMJBUndQVAA/fE9hYom6t/zqA248j0QAV/p LHH3hSirE1mv+7jpQnhMvatrwUpeXrOiEw1nHzWCqOJUZ4SY+HmGFW0YirWV2mYKoaGO2YBU wYF7O9TI3GEEgRMBIRT98fHa0NPwtlTktVISl73LpgVscdW8yg9Gc82oe8FzU1uHjU8b10lU XOMHpqDDEV9//r4ZhkKZ9C4O+YZcTFu+mvAY3GlqivBNkmYsHYSlFsbxc37E1HpTEaSWsGfA HQoPn9qrDJgsgcbBVc1gkUT6hnxShKPp4PlsZVMNjvPAnr5TEBgHkk54HQRhhwcYv1T2QumQ izDiU6iOrUzBThaMhZO3i927SG2DwWDVzZltKrCMD1aMPvb3NU8FOYRhNmIFR3fcalYr+9gD uVKe8BVz4atMOoktmt0GWTOC8P4= In-Reply-To: <6985a62f-a091-4087-887c-361570170ef6@oracle.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.133.124; envelope-from=clg@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Joao, On 3/5/25 12:16, Joao Martins wrote: > On 14/02/2025 13:05, Cédric Le Goater wrote: >> +Kirti >> +Joao >> >> On 2/13/25 22:45, Alex Williamson wrote: >>>> + >>>> +    /* >>>> +     * Migration support >>>> +     */ >>>> +    object_class_property_set_description(klass, /* 5.2 */ >>>> +                                          "x-pre-copy-dirty-page-tracking", >>>> +                                          "Disable dirty pages tracking >>>> during iterative phase"); >>>> +    object_class_property_set_description(klass, /* 9.1 */ >>>> +                                          "x-device-dirty-page-tracking", >>>> +                                          "Disable device dirty page >>>> tracking and use container-based dirty page tracking"); >>> These are really debug as well, right?  They just happen to be >>> migration related debug. >> >> I suppose so. I would rather keep them under the migration topic >> and add 'debug' in the comment. >> >> Changes : >> >>   commit bb0990d1740f ("vfio: Change default dirty pages tracking behavior >> during migration") >>   commit 30b916778517 ("vfio/common: Allow disabling device dirty page tracking") >> >> do not explicitly explain why these properties are useful in any way. >> >> Kirti, Joao, could you ? > > Sorry for the extreme delay but I was out travelling for the past 3 weeks for > vacation and work. > > The property is marked as x- but my intent was both debug/testing and to have > something that allows me to select the dirty tracker between device vs platform > dirty tracker if something is wrong with say VF dirty tracker or if there's some > limitations around it. These days we actually use it a lot as my default to have > IOMMU dirty tracker in use. I wouldn't label it exclusively as '(debug)' just yet. > > The precopy option might be to avoid dirty tracking at all and it's generally > useful when you don't have dirty tracking at all or say snapshots or 'offline > migration'. But I have never seen real use of it, or need for that matter, > except the early days of VFIO migration during testing. Could you please send a patch on top of : https://lore.kernel.org/qemu-devel/20250217173455.449983-1-clg@redhat.com/ This would be great to keep the information in the git history. Thanks, C.