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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 C6577CF256B for ; Wed, 19 Nov 2025 09:15:52 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 844D410E5B9; Wed, 19 Nov 2025 09:15:52 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="K7b9fkSm"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.12]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9927710E5B8; Wed, 19 Nov 2025 09:15:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1763543752; x=1795079752; h=date:from:to:cc:subject:message-id:reply-to:references: in-reply-to:mime-version; bh=VRd534ISdzOKCm81Cax46UUHEuzQyq7ANdvX1QhPFsg=; b=K7b9fkSmKsTnXcJerwKsTgEhTnMpII+RluslWL+fWfWQYgDqotNKlQjM wF6Hlvd+wVoPqLt9SEGrID0mXDM1X/wfWn/D8PXEdRnXulG9vHqDf2XpM bsvglYSiLz0OyfHeCqZoSRS/MorFBDlFEWB1KlMtxKfeOOVUwWgdYCt8V q0By70/sBrsxJ0n3HkOLl3V/E2luoH4PD6UwauHpdf5GtEFJuWgJQ+igA EI+wNvLr7ba7LkS1S2osx3syAA7bFhQj1xLysOWjiZRSCj//DpM72naYb xqilHgI1eGUBs8kGWD5RVu/dcZuPaR8gssW4XS4COma2My3KLfxahqKoM w==; X-CSE-ConnectionGUID: amsYZxNuTPuAi9V5cW2lHg== X-CSE-MsgGUID: erZL7ncFR7+VNr5l0csnKQ== X-IronPort-AV: E=McAfee;i="6800,10657,11617"; a="77036304" X-IronPort-AV: E=Sophos;i="6.19,315,1754982000"; d="scan'208";a="77036304" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Nov 2025 01:15:52 -0800 X-CSE-ConnectionGUID: Czcfaw4sTnCaRDwm861Adg== X-CSE-MsgGUID: F5ZsVfmyQDurLVDUIuksKQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.19,315,1754982000"; d="scan'208";a="190802324" Received: from fmsmsx903.amr.corp.intel.com ([10.18.126.92]) by fmviesa006.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Nov 2025 01:15:51 -0800 Received: from FMSMSX902.amr.corp.intel.com (10.18.126.91) by fmsmsx903.amr.corp.intel.com (10.18.126.92) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.27; Wed, 19 Nov 2025 01:15:50 -0800 Received: from fmsedg901.ED.cps.intel.com (10.1.192.143) by FMSMSX902.amr.corp.intel.com (10.18.126.91) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.27 via Frontend Transport; Wed, 19 Nov 2025 01:15:50 -0800 Received: from CY3PR05CU001.outbound.protection.outlook.com (40.93.201.25) by edgegateway.intel.com (192.55.55.81) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.27; Wed, 19 Nov 2025 01:15:49 -0800 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=pPI02YZK36PpgjMw0C7chlSt7RPuaDJM6Ho91DYlu4KUkI7D6GrzgqUOQwj+TvO/IdFqCkxsz6JjR+IdVTXkq0sPdTHQ85Bx0v2gCqt6xoz4ZjYNi1jQPnJkVSrQKOkykggfDmO3/JVU+0OS06jIRHK6L6PKTUFQ1Q81WA8UIj6MU3jzKXPiBdElNuYj1CaeBPtl40TfCekEDCoD9FOnaBKW+KbzdQRXob5LU/ttEJfgRZWd8w3By27mIJLAYUF4ujEFQ638nDnWpxM0Z66Sd9D0Mv5F17casFlo43GqR3PlBqjQ/21r2TFvUOMNHYs/w53MRVqyIdVrt5jEhASFPw== 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=ptd2nbdlUlImQAF+GB7XiXmurgLglxjO+N7d0RDK0Gw=; b=CPIc7vfH3eO1q7N06pVG5vEu4DeGhipzlMGWn0KbKoP6W6TtUaKsyMWG2ZUep99rDp9Z/3e1a0QhoKX+goHHauv3wet0MMSWTfM2ZjCVyS+1Pie8SFc0niYAzPRYtU/YHz/T73prRn/Vbxmq3nms1eYsIqXWBIN9V/LZhk8Xr3NmQ2VYL/4w/0Vl6AvwbzA3JICUf/uZTQd+4yqdDVye+bYnEgNDrmjJq6NcNWs56+nP3da07+EHgorK+viTU05NzWOY3pVMnNsDpIxCqGSIsVkKNb+wuuGr4ZrUAILKkrej1iaHp0B0T3kQl5BB92srJ1C0ke1kGMyH9laV9jlGeg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=intel.com; Received: from SJ0PR11MB4845.namprd11.prod.outlook.com (2603:10b6:a03:2d1::10) by SJ5PPF64191BB3C.namprd11.prod.outlook.com (2603:10b6:a0f:fc02::82f) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9343.10; Wed, 19 Nov 2025 09:15:42 +0000 Received: from SJ0PR11MB4845.namprd11.prod.outlook.com ([fe80::8900:d137:e757:ac9f]) by SJ0PR11MB4845.namprd11.prod.outlook.com ([fe80::8900:d137:e757:ac9f%3]) with mapi id 15.20.9343.009; Wed, 19 Nov 2025 09:15:42 +0000 Date: Wed, 19 Nov 2025 11:15:35 +0200 From: Imre Deak To: Suraj Kandpal CC: Jani Nikula , "dri-devel@lists.freedesktop.org" , "intel-xe@lists.freedesktop.org" , "intel-gfx@lists.freedesktop.org" , "Ankit K Nautiyal" , Arun R Murthy Subject: Re: [PATCH] drm/display/dp_mst: Add protection against 0 vcpi Message-ID: References: <20251113043918.716367-1-suraj.kandpal@intel.com> <689e22d69f7ad9be4f4a78b5194d8c4965be8ca8@intel.com> Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: LO4P302CA0013.GBRP302.PROD.OUTLOOK.COM (2603:10a6:600:2c2::20) To SJ0PR11MB4845.namprd11.prod.outlook.com (2603:10b6:a03:2d1::10) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SJ0PR11MB4845:EE_|SJ5PPF64191BB3C:EE_ X-MS-Office365-Filtering-Correlation-Id: e0ecfb3a-ed20-4591-9ef2-08de274c36a9 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; ARA:13230040|366016|376014|1800799024|10070799003|7053199007; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?Et50zkvJbLX3mqFj5ZcQNtaCxe7sQmuxIGEnx3RcDRYPjUSwjbdTgQuHmrws?= =?us-ascii?Q?Ks8BMdT+c5gPoLw/eLu2qzfs8R+qNvAmdb0ATWS3dWvqssgn/AfQ2a9iq9Wn?= =?us-ascii?Q?+/T/jBQ/1zgUqzYZuK5Kw/uBHeiVAKcu0j65TxUFEUka99QVu0Akope8VIg7?= =?us-ascii?Q?o1qIIJhc0gpBJuBbDhj7r9qf9kFHetg3nxH2qntyz1q4iI6HfiJYZUaZhPTL?= =?us-ascii?Q?LTI8iqGZmHegetSlBTMf3lPCFZV1vAMJ9zscdPCpFEcUswWlpkkps/lrc2vR?= =?us-ascii?Q?eib/aJUMJtn+/y6CqPm5ShAsIeUKFv+N21nGsLvJZUOKz8v1YCESiwc8BJK2?= =?us-ascii?Q?baTFpQHBa+VZr25KZL/MjJi+SyjU2AG+nWCfKBEaFhw56Rc1GaLj/cwCIK7N?= =?us-ascii?Q?ARCi9DMPVrYN7p4LT/67qv3vokNV7ptAHkt/sdLq8czw3BkMaZ9B0DGgSyKv?= =?us-ascii?Q?O9htURCgKjWGVR75Qlkk2KfQuOvlGHeSHgqxRIleHhJ8WqLL6jeuvzIInPiF?= =?us-ascii?Q?jUpnJzWw4ibcT4KYlfbxXx3Ohe/p2CcAh5CBTG5BT97gmoAMFhdwhZ4RTm16?= =?us-ascii?Q?rVPyHnhx/9lDskQdBYW5bJvB8tL7lLeyX3Fe/ESScjNxQQ8Y6oYO7xCCj9dy?= =?us-ascii?Q?GyQScmGaRfGCc6VSzqLMKOONrrmS2LfSWhSh2vGybeyhY5/8Gin5XIbwis8o?= =?us-ascii?Q?aWqYz7rxCrGSmI1XY18xa+om24ro/ii5ZwG7cZMwAFiuwDuUjRUYxSA+paoN?= =?us-ascii?Q?wMl5Fg81RZNXz+NLwpqPbMvSgNceNVuWeEEluHrsJxbWXchD/kUzm93VdXLM?= =?us-ascii?Q?XKJu88FXTo55F3gCYBYUIgbJb+8Z4dWyCkSZ1d9kBS5AC+3Ax7+M56CpKXQA?= =?us-ascii?Q?zlH/KEI/TBo7ONmMgkA2J3FcBKuCqV+xUXFziDItLA9a0Qci02AuMeap11Vr?= =?us-ascii?Q?Qk3P3qWjWTRNPVYeC1Op5QFJHYkgD8RmEgZFxU0AfDSsKhhyt93+4UWQgoDX?= =?us-ascii?Q?NDBlwtSHK+hmdmNeLjVkdd9uIRDE8PTxR82HinFULUJYHZnd1Bhc4LWiGfxv?= =?us-ascii?Q?8FBc/0wf+y42kdNYCgtQOVe8KtmmMxC87sPvYBeShyQpx+oPFeU6IuGIsIgS?= =?us-ascii?Q?0ZThDcoE7X01ZDfiRgrSroyF5VYFSBR2QtqokBN/KrOdNspwSSGojgClo644?= =?us-ascii?Q?HKQYeEsg7ikWjOb5WhoBYzUfGVJYB5z8pXjHfMwz8Rr45SLTxmrUiL4FzHR0?= =?us-ascii?Q?8ag8mV4et+qh4zmwsaa342/MG8WkwrCPEkBOW2wmvvZWhIrZwTYVIgBgOswI?= =?us-ascii?Q?Vf+96wNU0AoWpYQHEsONLtE7e8mU5KPUokJjFmYac3CpPIK5ErFiSDWFp0ep?= =?us-ascii?Q?UTBr4lwSf+MtQgnATLuuAYVSiyOi9D0NX35Zw2qAa/3IE5eHG80febl6RvZY?= =?us-ascii?Q?CYWTKVVn9QrYc1CTUnVhjldQL/fhGkmx?= X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:SJ0PR11MB4845.namprd11.prod.outlook.com; PTR:; CAT:NONE; SFS:(13230040)(366016)(376014)(1800799024)(10070799003)(7053199007); DIR:OUT; SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?arJF9rY1UYwmp38g5U39JcjV0O4ur6M6tdIp5p+wS0byAT50WdykjoaFumAX?= =?us-ascii?Q?le0vnEYAN01lMLFTcGrsX71WNedFkTu9lDPwXZIerxwsz+XW68zVg4h20YJQ?= =?us-ascii?Q?z+HXkWir+MJt6mqY/DaKjtFWsUpSSetY0x0b3v+kbCb1mfcD4ChVAFrW4WE0?= =?us-ascii?Q?FbkZKbaCsZufo4LZMkPxlSnGIUAMqZiXDS4hcHJHu1EqzvlUasRR3numM+ay?= =?us-ascii?Q?wuucsOEkIqEqHouRMwYOy7BvMnnkFT4vX9FgptSrhH5rqv98SRH4t6uKXny9?= =?us-ascii?Q?JRLNmBZrn9rqY4gb3EIxMzm6fUOJJI5Oya9RVSA9ps51W8VIY4ZeWPlT5ehU?= =?us-ascii?Q?b4eVhVJu2s3BYNnQFTYWb65RkaBKu4I+OcLAPHA4mzItlf1hSSwg7F9v/L2C?= =?us-ascii?Q?+7CFoAqCGSqoW1b+d6OZA9bN1ho5BGt29UtOlWAfnxaYkzPwi5e4uIt4GpCi?= =?us-ascii?Q?erLitdU8ZIEXcHjtAiK+SjCmLw+Jscx1Zm21WFkNTSSktk9EFRjyeGlVYwnn?= =?us-ascii?Q?u291gxo/divfI7rUvIzldBHvG+HueF4BQkTjh4KsD7CphrK8FDhbfKSEISqe?= =?us-ascii?Q?2ZOHxAIlzhnbwzJh+3FeR9H+GQBYkljX35YQZEhMWevgl21qXtox2u6RQP4G?= =?us-ascii?Q?dLMvmiCNQOwvMSFWgtblU+L12HAI6hK08b63aY5+9OQn2SahcU6yz77ucxNq?= =?us-ascii?Q?l4RqFPqroq22k2Vy4Oo7+Jws0e4r6YJOsl8lbsNfVsJadMUi8Nsy0gMqsyez?= =?us-ascii?Q?bo/Cy/XMDoBikKjTIgpiMwu2E/bHqaiG/0ymmLiC9C5QH3sWr9V+duCz2fJA?= =?us-ascii?Q?yvFsXc1uPHcmZfIDC0lWLq0sXohs9XUYDsfEUjJuV33xCMcT9diaxYY720/7?= =?us-ascii?Q?ju81uEUcuw/eFUR/i7GX8z37kubhcOOHcKqvsPJI47L9r29imJUv+uT2nNOV?= =?us-ascii?Q?3N0KT1wa/ExGQZ5HaluoVT34VGIMYPql70AHo6iAdttxo93KDgdb7pLL3OiY?= =?us-ascii?Q?k9OxaW6hHoFRL/3W5W/Gdq3BHfnaQSG9izwlQZMVrxTID4llIF7g2r7dirSV?= =?us-ascii?Q?3Pc78UWkaJxlEj+LxCmFUuI+ZwByowvJyu6HEozutB6TdlAN5SW3Tc2dE7sl?= =?us-ascii?Q?jlrYU6rX3YcqO4/bVFekgkD3cS9pDauO+b8NY4YEvBxpr8jd1aVawQANdWO4?= =?us-ascii?Q?UJ3ANU6nOmWcPuchKfLPargL66Syk+Z2xUXaK/F+X3KtVgO9Hm8hunkmHPnC?= =?us-ascii?Q?UbhNKUFmxTsKFa8I4xeXkMUcv6pIwdQjFTLRLUu1r1Mpu8MmpY1ItGZOZsgD?= =?us-ascii?Q?tyojBL1LBO2tQMvP/gOqbI3Kdk674I1840HRXB4FWP0M7XluHKcSctmPUXum?= =?us-ascii?Q?Djz0zwAeeBFJWyCd6UpdZhJ+Xyry3czCLI0YMPRg1sf5ekt3MrFtAzCN2xIW?= =?us-ascii?Q?8e2EBT+HvYsQ14rbaJWcAXFSKPjm3KWv2kixb7oZYotN2xqvdPQ6ou69wP9l?= =?us-ascii?Q?frXhG3rrsZBKrbFOeGm+RalXPJg0ffYA2VGb+6FZpWd8bZULM96wJ/AAXmQG?= =?us-ascii?Q?aj+QVtTDTALPxAQkP0sLrK5IhOvJjT+yXl2IsEdmBlDnyAw17aNscy9D7zEl?= =?us-ascii?Q?M9+6xGwWFB7FnYiZ3+3ckIH2M1ebYmnB3EX+S1+MTMC+?= X-MS-Exchange-CrossTenant-Network-Message-Id: e0ecfb3a-ed20-4591-9ef2-08de274c36a9 X-MS-Exchange-CrossTenant-AuthSource: SJ0PR11MB4845.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Nov 2025 09:15:42.6114 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: mM9QwCReLOHy+jKUO4SKPUyPqaDrVrjOyKySjVokezC+z075fKottJ0JZK8MZoAN4j06kc3+gFPkRrpKtivPvg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ5PPF64191BB3C X-OriginatorOrg: intel.com X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: imre.deak@intel.com Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" On Wed, Nov 19, 2025 at 09:38:10AM +0200, Suraj Kandpal wrote: > > Subject: Re: [PATCH] drm/display/dp_mst: Add protection against 0 vcpi > > > > On Mon, Nov 17, 2025 at 07:09:38AM +0200, Suraj Kandpal wrote: > > > > -----Original Message----- > > > > From: Jani Nikula > > > > Sent: Thursday, November 13, 2025 9:55 PM > > > > To: Deak, Imre ; Kandpal, Suraj > > > > > > > > Cc: dri-devel@lists.freedesktop.org; intel-xe@lists.freedesktop.org; > > > > intel- gfx@lists.freedesktop.org; Nautiyal, Ankit K > > > > ; Murthy, Arun R > > > > > > > > Subject: Re: [PATCH] drm/display/dp_mst: Add protection against 0 > > > > vcpi > > > > > > > > On Thu, 13 Nov 2025, Imre Deak wrote: > > > > > On Thu, Nov 13, 2025 at 10:09:19AM +0530, Suraj Kandpal wrote: > > > > >> When releasing a timeslot there is a slight chance we may end up > > > > >> with the wrong payload mask due to overflow if the > > > > >> delayed_destroy_work ends up coming into play after a DP 2.1 > > > > >> monitor gets disconnected which causes vcpi to become 0 then we > > > > >> try to make the payload = ~BIT(vcpi - 1) which is a negative shift. > > > > >> > > > > >> Signed-off-by: Suraj Kandpal > > > > >> --- > > > > >> drivers/gpu/drm/display/drm_dp_mst_topology.c | 4 +++- > > > > >> 1 file changed, 3 insertions(+), 1 deletion(-) > > > > >> > > > > >> diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c > > > > >> b/drivers/gpu/drm/display/drm_dp_mst_topology.c > > > > >> index 64e5c176d5cc..3cf1eafcfcb5 100644 > > > > >> --- a/drivers/gpu/drm/display/drm_dp_mst_topology.c > > > > >> +++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c > > > > >> @@ -4531,6 +4531,7 @@ int drm_dp_atomic_release_time_slots(struct > > > > drm_atomic_state *state, > > > > >> struct drm_dp_mst_atomic_payload *payload; > > > > >> struct drm_connector_state *old_conn_state, *new_conn_state; > > > > >> bool update_payload = true; > > > > >> + int bit; > > > > >> > > > > >> old_conn_state = drm_atomic_get_old_connector_state(state, > > > > >> port- > > > > >connector); > > > > >> if (!old_conn_state->crtc) > > > > >> @@ -4572,7 +4573,8 @@ int drm_dp_atomic_release_time_slots(struct > > > > drm_atomic_state *state, > > > > >> if (!payload->delete) { > > > > >> payload->pbn = 0; > > > > >> payload->delete = true; > > > > >> - topology_state->payload_mask &= ~BIT(payload->vcpi - 1); > > > > >> + bit = payload->vcpi ? payload->vcpi - 1 : 0; > > > > >> + topology_state->payload_mask &= ~BIT(bit); > > > > > > > > > > This looks wrong, clearing the bit for an unrelated payload. > > > > > > > > Agreed. > > > > > > > > The logs have, among other things, > > > > > > > > <7> [515.138211] xe 0000:03:00.0: > > > > [drm:intel_dp_sink_set_dsc_decompression > > > > [xe]] Failed to enable sink decompression state > > > > > > > > <7> [515.193484] xe 0000:03:00.0: [drm:drm_dp_add_payload_part1 > > > > [drm_display_helper]] VCPI 0 for port ffff888126ce9000 not in > > > > topology, not creating a payload to remote > > > > > > > > <7> [515.194671] xe 0000:03:00.0: [drm:drm_dp_add_payload_part2 > > > > [drm_display_helper]] Part 1 of payload creation for DP-5 failed, > > > > skipping part 2 > > > > > > > > <7> [515.347331] xe 0000:03:00.0: [drm:drm_dp_remove_payload_part1 > > > > [drm_display_helper]] Payload for VCPI 0 not in topology, not > > > > sending remove > > > > > > > > So it's no wonder the port's not in topology and everything fails. > > > > We obviously need to skip payload_mask updates when the VCPI is 0, > > > > but that's just a symptom of other stuff going wrong first. Perhaps > > > > we could do with some earlier error handling too? > > > > > > Yes I agree the question is how high will the error handling needs to be > > added. > > > A lot of weird things going on here. > > > > > > 1st one is how is it finding a payload which we do not create while we > > > call destroy function > > > > > > 2nd how is VCPI with id 0 possible from what I see VCPI are 1 at least > > > that's what I gather from > > > drm_dp_mst_atomic_check_payload_alloc_limits.So what are we missing > > when we create a payload? > > > > > > Imre, Jani any idea still new to how payload creation work so am I > > > missing something. > > > > A VCPI ID will be assigned to a payload during an atomic commit only if the > > corresponding MST connector is still connected. If the MST connector gets > > disconnected by the time of the atomic commit - as in the above case - no VCPI > > ID will assigned and the allocation table in the branch device cannot be > > updated either for the payload, as indicated by the above payload > > creation/removal failed messages. > > > > I think the fix should be not to clear the VCPI ID if it's 0. Valid VCPI IDs start > > from 1. > > Hmm then in that case should we just return 0 early if vcpi turns out to be 0 here. The payload should be still deleted, so only the clearing of VCPI ID from payload_mask needs to be avoided if the ID is 0. > Regards, > Suraj Kandpal > > > > Regards > > > Suraj Kandpal > > > > > > > BR, > > > > Jani. > > > > > > > > > > > > > > > > > >> } > > > > >> > > > > >> return 0; > > > > >> -- > > > > >> 2.34.1 > > > > >> > > > > > > > > -- > > > > Jani Nikula, Intel