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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ABA2DC433EF for ; Mon, 4 Oct 2021 15:20:09 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 7622F61248 for ; Mon, 4 Oct 2021 15:20:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 7622F61248 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E0ADB6EA3A; Mon, 4 Oct 2021 15:20:08 +0000 (UTC) Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4E0626EA3A for ; Mon, 4 Oct 2021 15:20:08 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10127"; a="248727380" X-IronPort-AV: E=Sophos;i="5.85,346,1624345200"; d="scan'208";a="248727380" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Oct 2021 08:04:05 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.85,346,1624345200"; d="scan'208";a="544333147" Received: from fmsmsx603.amr.corp.intel.com ([10.18.126.83]) by fmsmga004.fm.intel.com with ESMTP; 04 Oct 2021 08:04:05 -0700 Received: from bgsmsx602.gar.corp.intel.com (10.109.78.81) by fmsmsx603.amr.corp.intel.com (10.18.126.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2242.12; Mon, 4 Oct 2021 08:04:04 -0700 Received: from bgsmsx604.gar.corp.intel.com (10.67.234.6) by BGSMSX602.gar.corp.intel.com (10.109.78.81) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2242.12; Mon, 4 Oct 2021 20:34:01 +0530 Received: from bgsmsx604.gar.corp.intel.com ([10.67.234.6]) by BGSMSX604.gar.corp.intel.com ([10.67.234.6]) with mapi id 15.01.2242.012; Mon, 4 Oct 2021 20:34:01 +0530 From: "Gupta, Anshuman" To: =?iso-8859-1?Q?Ville_Syrj=E4l=E4?= , "intel-gfx@lists.freedesktop.org" CC: Sean Paul , "C, Ramalingam" , "B S, Karthik" , "Nautiyal, Ankit K" Thread-Topic: i915 MST HDCP code looks broken Thread-Index: AQHXuQ3RWUOlebNYx0qBcd6MMk1Xm6vC7bqQ Date: Mon, 4 Oct 2021 15:04:01 +0000 Message-ID: <9078bb70f03e41738043771fb1d89ff3@intel.com> References: In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: dlp-product: dlpe-windows dlp-version: 11.6.200.16 dlp-reaction: no-action x-originating-ip: [10.223.10.1] Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [Intel-gfx] i915 MST HDCP code looks broken X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" > -----Original Message----- > From: Ville Syrj=E4l=E4 > Sent: Monday, October 4, 2021 4:22 PM > To: intel-gfx@lists.freedesktop.org > Cc: Sean Paul ; Gupta, Anshuman > ; C, Ramalingam ; B S, > Karthik > Subject: i915 MST HDCP code looks broken >=20 > Hi, >=20 > I took a quick peek at intel_dp_add_mst_connector() the other day and not= iced > that it calls intel_dp_hdcp_init() and passes in the SST dig_port. And di= gging in a > bit further that seems to clobber all kinds of things in dig_port->hdcp_p= ort_data. > This looks rather broken to me. >=20 > So has anyone actually thought what happens if you first use MST on the p= ort, > and then later switch to SST on the same port? AFAIU there shouldn't be , when the last connector of MST topology get dest= royed and it switches to SST mode on same port. The base static connector of same dig_port should get connected and will ca= ll intel_dp_init_connector()->intel_dp_hdcp_init(). What is the specific sequence is broken here , is it the connector destroy = path ?=20 > -- > Ville Syrj=E4l=E4 > Intel