From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from NAM02-DM3-obe.outbound.protection.outlook.com (mail-dm3nam02on2080.outbound.protection.outlook.com [40.107.95.80]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AF0901A0BDB for ; Wed, 26 Mar 2025 13:05:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.95.80 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742994329; cv=fail; b=olJ/eTAxTxnWcviNds+Z8XqMvs3e5NjeRClcEEMIyX6xAyTymzu/qZDEIKlxxE8KFrQKtxeZc0DoujaRRunHX7gSZiy5zM6NAStpOLsCUjvWySmFF7KvE9yJdSLuPwFqpM0VR2vZ5mE0/zIoLVguQ3vYrirTeSaAAchFq8uOCXc= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742994329; c=relaxed/simple; bh=TRlcUZ0B+DvURGAoYHSvPgnCuMLqTTtRIX+DLzjrTwM=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=AwvPS/kVXTqUj4bWrxDO6Ar2sRLdgSwo7wG/jPgBjFf6t4XxG4OPvy4VR8S+N5NUrXYb4NrhdAuHfbwZ2/QaAAC5t7gq0lB9A3Qs0+E8fUHOk0PIMmVwwvRtkhUW2DWbZMY2gu+TIb1Sduw6ZKLaeGEWGciCIIzBW5BaZC39ucA= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com; spf=fail smtp.mailfrom=amd.com; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b=HfB+S4+g; arc=fail smtp.client-ip=40.107.95.80 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=amd.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b="HfB+S4+g" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=hDQAbu9StzMDF3ygTJH2ZhP7YMApx734wM0A/LVH0mUZZt9ipaQOkqZDkjD4Wq8FOfQQm5MShnHeDuG31wtz1A8hXsCQNgFcM9PS4NWn+1XAhPWoP5k2tzNLDa1yao5CWTnCVR60IW6BB8Eijrqo5moYFz/VBAjS/L7Cy3B/9X9/iw4HFmrjuYPIH6kDJ2BcR+iLNSphFd/A+aSu+kIhlF5BjEdct9pnJE5aiMFyMFTrUXF9LYpSynyHcY7j3lciL5bScn6q6diBpw7fiErRyCg86yHHWuLplEHwBjqCbZSZcASqvnxi5OTcp9tkFWtzCU+JruS2Ku7dmFKB+vPMGQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=K62xCvMvu+m20ngsJc2enRmtWlVOJ56KFKmB6esKvBk=; b=RFj2iTsgUGYGgzFLKLE+StpVkaSvlhYhOPKn/twxszAsUXOUWXBVkAuvrrAaF4IPZ/vEbZQ3Ud1FnXv1MGUTuNVf/S3QSaBXTHcgvDAe1Up2/YuO9YiW59tdXczquAT+tRszo7/ZPo8uJ6/dxy8AVSdUVz2hRokXE63LyOe3HpNd2nMj1eTpi60HUnAcaJbStfrINt0ukP2zbFsRQopYwlvCMXlrmDQ6q9fzCXE1K70aTWsIIgahHgE1r3Fq4OBvEXZeG6lCb7SmzDl5Ym+Y8LQzFbO5kTn0lu/e9ZfnfxPJCgzvdkW1E1UOCgTt0QT/dse+pm408lPAxvlFtqUopQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=K62xCvMvu+m20ngsJc2enRmtWlVOJ56KFKmB6esKvBk=; b=HfB+S4+g1a45Lw+pkjNCBlhV2yIFA4zTDLk7V9bhDlYNpIow1PWuTrr3LNz9v71dRkRBM69K3hFu0jFRDJV3EQnoBG/poDj/kPreXwet0+WCUAccPucGKwESKjmyGcDGGDmwt1eCSghhU2Q9L7I3vDl5AsiM9Y1OrigPIcpyBWc= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from PH7PR12MB5685.namprd12.prod.outlook.com (2603:10b6:510:13c::22) by LV3PR12MB9186.namprd12.prod.outlook.com (2603:10b6:408:197::16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8534.44; Wed, 26 Mar 2025 13:05:24 +0000 Received: from PH7PR12MB5685.namprd12.prod.outlook.com ([fe80::46fb:96f2:7667:7ca5]) by PH7PR12MB5685.namprd12.prod.outlook.com ([fe80::46fb:96f2:7667:7ca5%5]) with mapi id 15.20.8511.026; Wed, 26 Mar 2025 13:05:24 +0000 Message-ID: <94eeb36a-9aa5-4afd-9ba6-76e8ace10122@amd.com> Date: Wed, 26 Mar 2025 14:05:18 +0100 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] drm/nouveau: prime: drm_prime_gem_destroy comment To: Chris Bainbridge , Danilo Krummrich Cc: nouveau@lists.freedesktop.org, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com, simona@ffwll.ch, lyude@redhat.com, sumit.semwal@linaro.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org References: <00e4d9c4-ecfc-4784-b603-12db04cda806@amd.com> <1f4a534f-8883-4793-b191-60c2773f6217@amd.com> Content-Language: en-US From: =?UTF-8?Q?Christian_K=C3=B6nig?= In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ClientProxiedBy: FR4P281CA0104.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:cb::7) To PH7PR12MB5685.namprd12.prod.outlook.com (2603:10b6:510:13c::22) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH7PR12MB5685:EE_|LV3PR12MB9186:EE_ X-MS-Office365-Filtering-Correlation-Id: 88faf40f-0f06-4b7e-160c-08dd6c66def2 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|7416014|376014|1800799024|7053199007; X-Microsoft-Antispam-Message-Info: =?utf-8?B?TGlJZTNKRzZDYWtOZVJVbEthdytWcS93Z1BvNlY1L3RYMTVBYStDMEJqa0p4?= =?utf-8?B?Y3d1aUhzcURBaTJXVU1FQk1abUxJdlkxODVhN29ORWNPSGx0R3A0Umc4UXFW?= =?utf-8?B?RktXN0ErUm4yQW5Ga3Q2ODRPaWNUdmszOVA4WGN6OTF6anpnV3lyU3FiOTBx?= =?utf-8?B?OFMydC8zUERGZFJncGcyYjI1YlEzMWE2UEJaRGVQUFRYM1ViM3p4R2hjTWxq?= =?utf-8?B?MVRxOHJQQUh4UHVjbWp4MlI4STdvZjlSdEdRd1ZnbHJZT3gvUExtZjNCRUhH?= =?utf-8?B?ejlXOFFYVEhGMDE5cm9GYlpIQk16b1drcml2UkpMSkpPWnNzVHRDWHJ1Mjhk?= =?utf-8?B?L1pNOG5JUGNQVVZLTzNiSzBPNjNUWVYzRVZ4SnJKL2g3T3RjaEhxMmdrWVVH?= =?utf-8?B?QktmQjV1WUplVVJlQVUyc0l2L3pKQlpIY29kdk11V1RTdjFlTkhjdVBtdFNn?= =?utf-8?B?SnVtUHE5c2JGemdUbHNkelYySU1TTjFicDdSbnI3bE1xdm9DR2ROd2k4L0xU?= =?utf-8?B?VjM3aGNMdHRDR1FEaFFoT0U5YTh5SFNySk9TQzRZWWNVSkdyZTl5T09iZ1R0?= =?utf-8?B?V0NaeHN3a2M0YisrVkFZSlZaREdPUHlaTDJTS0p0Z0hYZnFWbXJ2RWZHQWpq?= =?utf-8?B?QnRkajJqSWdsVyt1VU1taVFXdDdhVEdEQmVUL3ZVS2dGL1M0cWg4Rkk5TFNM?= =?utf-8?B?bUs4enRqUjVINGx4QkNONm5PcFJrL1F0UXpTYjFSbVZ0V1VxdmVQKzV3YzYv?= =?utf-8?B?QkdNTnU1b1BvOThvaDRqZ1RKdXhzbStYUGszNDZpQ0xTNTZ4b1l4SnU0YkVk?= =?utf-8?B?U1REZVFScmlkRHBrQ1lwMjBDQXgwNk1SVW1zWFlHZzBWWVhHdmJaQ1Y4a1di?= =?utf-8?B?Nlo5cFpOSnhxdWhUTGY0WWluM0MzUUdMU3VUTnI2dUhFZzZxT28yczUrY1Jy?= =?utf-8?B?MGdaUTU1Tis1WGppYmw4Q0g3M3oxbFFpVXh1cnVMUW13K0dPREZWRXljSW1N?= =?utf-8?B?TWdJZFlMWWhTMEhkY2cxY1N2SmFrTkVQUk9CV2srUXc4cFA4blNibUNUVEFk?= =?utf-8?B?UnZYOFBXVHMwRUpyYXNTYkNEZmVTYUZLSlhZZnZFK1NVNEoreFpiVjFKL0lW?= =?utf-8?B?YXp4Y2I1Nmxub0pRY0NKY1FEL2oxVmtLRTM1T3hQd0krcnA5azROWW5JOXl2?= =?utf-8?B?REllb1RhbGZWMzZUQklyNjA2S1hXK0VnY2RZRnZCVjd1R05IbTVaaXVsODdz?= =?utf-8?B?ZE80M2d5SEErOExXOUlod2JpOEUyeEE3REJGNFpscHNESHF4L0Q0cWxuSDZu?= =?utf-8?B?cGR2aUJtZU1kZjZNQksvcFFQOHV4Tk1zMkFJRFY0T1ZIWEpjdGRSTXplbnB2?= =?utf-8?B?c0JaM2hXNDNxbDhHY1lXSGUvbVdjZjYvM3hFZ3N4RzhROXRMcTlLUHh1ejVt?= =?utf-8?B?QmxBOFUyTzRTM0JGa2FMcEdScGdBR1BlajJnRjUra0NpTEhoTlBxTnM4L3py?= =?utf-8?B?bmlTVHJZcFZLS2hqcThVcTM2bkloelR2dVpsK0F3cE1TaFFjT2ZMM2loSHVX?= =?utf-8?B?eTdEZlMwZy9EeHBSLzRtY0J4MlVodHVHUEtRY0JsRXQxeHNUOWs1amJPdXFp?= =?utf-8?B?alRFd3BQY2tBOFNxSXBzNDZQSkVwcFpCRXFaallpb1dyMCtqdXBrWHhBZ2c5?= =?utf-8?B?eUN4SWQwWUdGblJpUnB4M25QdnhoTVhBSGpDdDVYZ2RjZkNPRVpESHBXdFdD?= =?utf-8?B?aVgycXNyUFA1UUZwNGZVUGRmaGIrcWFYTWlydnNkcE9hSG5xeTdkRFNES01o?= =?utf-8?B?WmxLRDQvRTFMR1Y3c0FGUDkvbm1yNzdXZUlPcGtDSXczQWJ6UkNtNkxtb3BS?= =?utf-8?Q?/Gw0P3I/69kpa?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:PH7PR12MB5685.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(7416014)(376014)(1800799024)(7053199007);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?VXAvQytIZDR3TjQvOHBnSWU3OG5OU3dKLzVMYUhHYVU3a3RKYXB5NkEyNlR2?= =?utf-8?B?YWxZc3ZId1gxS3NYWWpISzdsRlR3SFIwSFFqU1Q3S2xESGJaWVZzVGt5TmF4?= =?utf-8?B?d3krUk4yRTFCTDlzaU41UFI1RjE5MmxsQVQ4QlZUbEV3Q3NkU3NhL1I4Q2xa?= =?utf-8?B?d3AwaXlNN0xXNlEzbnZxLzN5NllaNUhGY0Yva1ZBSHdsNDlaTWhEN0NVVHBS?= =?utf-8?B?ZmZvOEhIMDZ3eWwxV0pzS2xDcC9jZ0FrWVFQRGRiTEhIWTNZU0pYRHdlcmt4?= =?utf-8?B?Wm1IcG11MTQ3a2hNVDh1eGVYMnI1eVN1SzJXWWhRQUx1MGtRaUZyQ3hnRlI3?= =?utf-8?B?UE40Y1o4anN4eUhsNGVLN25EYVFnZklzYkttUzBvbVVjYm9qOS8yVFM2bFdF?= =?utf-8?B?MWxCMWZNYzEzeFc0SHUwdVI3ZTBXL0Y5RndCS0dnT2NzMXhFL1d2R0NsL3N6?= =?utf-8?B?WDlVV0dOdHV3anlyalBRYUtrSDladVRGSElvWk13cFFJd29NdmlnZUlVVWZm?= =?utf-8?B?SVVIMm9Rd3dOTzdVamIycS9DWm40WXpibURBTHZXa3VKdnBkNVdmYTZ5NW5x?= =?utf-8?B?SUo5bWZwQXJqc2c2ak9hbHoycVUvc0Q0ODNGZHY1TzY0ZElQS214TnJvSTZO?= =?utf-8?B?OWNBQVNoUmlwOVlyR3kyQkdjODJjcXBUV1FKUGdmMVg2ZExxeDJxalJ5cGlQ?= =?utf-8?B?RWJEQzdVRTM3TmpsT0hGblBSTFRrVEdhL3liU1Jvb1k0YXc2eDJCZkUwYUN6?= =?utf-8?B?ZE9xS2NUcEZRT3R4TkJ1UjdOc3ZBZXM5dDVvajhtQnlLTVZ2dER5Y05NZlhY?= =?utf-8?B?ZzhUVys3R0pmUjVJMUJKZWEyVVVWV2VvUkZ4YzZwb0h6NElyYW9VNXBSVXVM?= =?utf-8?B?Ni9PL2xCUkIyckkySUIxMlhrVnd4SU5mMUtsMC9mdFlXSlRhQ3g5TndibXo1?= =?utf-8?B?WG8zcHVmNjJvcHZ1VjVmK3k2cUsvSXdmV3ArOGVGU0JoQTBtQi9DWnJzbTF6?= =?utf-8?B?MWZJbkZHdVNCazBtVUx3aFNCVUNySis4MUhOQ3EwRGFZRTVPbmZFa3dId2Zl?= =?utf-8?B?Y3dPd0dHWmcyMXhPeDBEamsrOU5QTVZLblJvNzA5RTlqTXppZllheEo2VnlS?= =?utf-8?B?Wmd6MlRNSXNjLytqL3FZRjJQY3BRYVdtMkJ0ODZQOFppMnYrTGVZMDdyc1hX?= =?utf-8?B?dU9zcDdQMFpMUmNST1M3WHlFM1ltMERsS3ZJTjN1eS9EUmx5ZkthbzZIK1Jq?= =?utf-8?B?NXFmYmtpbG9mRTNLMVphWUJEaHdlWjJpeWdmWU5lTnN6V3o3VWFPdTZ0bUto?= =?utf-8?B?cHBtVHgrelB4dEhhb2Fkb2EydUJjQ3pOWjA1VmhRSk1RdXNuaHNxNDdyZ1l4?= =?utf-8?B?RTMwTS9GWTdUeDRFOFA4cG1lalNzZHQ2aVpnNXZlTXd0cVhJelFZWWtEZlp4?= =?utf-8?B?UVFMQmtKVjVlT3R6QzkzS2UyUS9vNGJvU0VyaTFrM1dMZVR2R1ZYdExzVTZ2?= =?utf-8?B?aG92R0NBeG5MQ09sUHVNUzdaRDFlQ1owQmFWRGo1eERJWjFHWXZyckxSQXZt?= =?utf-8?B?RWkvSVBTSER0YWJPeS9sSnk4N2ZIeEZWTThnVWN5NkZZWGpocXNjbFlKTm5O?= =?utf-8?B?cjJ2b1d5em0vUHBSTGJwdDhVY1RrWVZkTmVoWjg5eXVaOEl3Vk9wWVladm8v?= =?utf-8?B?R1p5d1k1R0ZFaHBwZDVXNHFvUDFvYVBWT2EyRHhmUis0ZUhDWUV0aHAwODZR?= =?utf-8?B?dENJTk1HSHZVektUczRwZy94eVlCY2UrL2VHV1ZwUjRhTWtma1lPWUlSRExW?= =?utf-8?B?dll1dUpQVlA0QVVtQmQrbVEzZUdNMnp2R3ZsK0JMTEtWK21mblB4ZmswWThU?= =?utf-8?B?cVJ2bkxVcDR1bEZqN2Q3eEk4S3hicWp3S0JhVllqZHVxUm45VVFmQXU0c2RT?= =?utf-8?B?blIvTTFMdHN6OFdUWHF3TjR4SElIUTJIQ3RHYVF3QkNXVmZ6YnZQSjBLUUlx?= =?utf-8?B?T0FSV3U2RGczN2VhUmw5azEvNTF4elZrem5JYkhZWWFQTzlEVmpFNmxUM1R2?= =?utf-8?B?aXFWN3Vob1JTcm1GVldSL0xXeEFiQjJtWTdQNVFuNjVBdlRPOWJIRTdvVlhB?= =?utf-8?Q?CxUByZtITDaNDAQgUGXRsg4pj?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 88faf40f-0f06-4b7e-160c-08dd6c66def2 X-MS-Exchange-CrossTenant-AuthSource: PH7PR12MB5685.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 26 Mar 2025 13:05:24.0887 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: COfvcCI1MYaFJ6Qk/ISXuUBNCKveloghM31OLPdA21D6i3wzcPRnWk16krKGeYqj X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV3PR12MB9186 Am 26.03.25 um 13:53 schrieb Chris Bainbridge: > Edit the comments on correct usage of drm_prime_gem_destroy to note > that, if using TTM, drm_prime_gem_destroy must be called in the > ttm_buffer_object.destroy hook, to avoid the dma_buf being freed leaving > a dangling pointer which will be later dereferenced by > ttm_bo_delayed_delete. > > Signed-off-by: Chris Bainbridge > Suggested-by: Christian König The subject line of the patch should probably read "drm/prime: fix drm_prime_gem_destroy comment" since this isn't nouveau specific at all. It's just that all other TTM drivers except for nouveau got that right. Regards, Christian. > --- > drivers/gpu/drm/drm_prime.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c > index 32a8781cfd67..452d5c7cd292 100644 > --- a/drivers/gpu/drm/drm_prime.c > +++ b/drivers/gpu/drm/drm_prime.c > @@ -929,7 +929,9 @@ EXPORT_SYMBOL(drm_gem_prime_export); > * &drm_driver.gem_prime_import_sg_table internally. > * > * Drivers must arrange to call drm_prime_gem_destroy() from their > - * &drm_gem_object_funcs.free hook when using this function. > + * &drm_gem_object_funcs.free hook or &ttm_buffer_object.destroy > + * hook when using this function, to avoid the dma_buf being freed while the > + * ttm_buffer_object can still dereference it. > */ > struct drm_gem_object *drm_gem_prime_import_dev(struct drm_device *dev, > struct dma_buf *dma_buf, > @@ -999,7 +1001,9 @@ EXPORT_SYMBOL(drm_gem_prime_import_dev); > * implementation in drm_gem_prime_fd_to_handle(). > * > * Drivers must arrange to call drm_prime_gem_destroy() from their > - * &drm_gem_object_funcs.free hook when using this function. > + * &drm_gem_object_funcs.free hook or &ttm_buffer_object.destroy > + * hook when using this function, to avoid the dma_buf being freed while the > + * ttm_buffer_object can still dereference it. > */ > struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev, > struct dma_buf *dma_buf)