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 6488CF34C62 for ; Mon, 13 Apr 2026 15:38:20 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 034A510E3CE; Mon, 13 Apr 2026 15:38:20 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="mgapVcy9"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.17]) by gabe.freedesktop.org (Postfix) with ESMTPS id B096310E3CE for ; Mon, 13 Apr 2026 15:38:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1776094698; x=1807630698; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=wr95eOWOsM0jEhU6/TCrUt1EFA/gQBdn59k27WWefDA=; b=mgapVcy91w0mxA2015eghsQ9Gs46fRpEychtJVnLuc7FBHLGIbaDeEJn FklLxiGqn1dPU0E+6mthKtfVY1+IsSs8mK9NuC5YjwdDOcr8knQfyQDmx jQn2O/DN9RBDIFbO6WY2reCSFguJaVYo/65wZbagJTqF8gtp5XqWr16jb IBhexIJ77JI66rVKzEvq2VhpxdW7ndGGYwFCiP1f2lEEgKZmYc0zCmUec tI8wZBiMMoXGUN+jwgA6TAqKw3OvYvMXL4TUocodbJ3vUQqx/2RIbjo1H fK+G3/5wuN7mu9WloIVuHfaM/ebce13axbZHN16ka3thJDOeBntLtRAFC w==; X-CSE-ConnectionGUID: oyOdTqbfSQqQxhq+cB0Oyg== X-CSE-MsgGUID: h+pQYNEESw2SaEqLwtxJjQ== X-IronPort-AV: E=McAfee;i="6800,10657,11758"; a="76997227" X-IronPort-AV: E=Sophos;i="6.23,177,1770624000"; d="scan'208";a="76997227" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by orvoesa109.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2026 08:38:18 -0700 X-CSE-ConnectionGUID: yJxeQMjURI2vbfhzZ6irag== X-CSE-MsgGUID: +iRe5Rs6ScW+NTpFSyK5kQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,177,1770624000"; d="scan'208";a="225087146" Received: from dut4086lnl.fm.intel.com ([10.105.10.78]) by fmviesa006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2026 08:38:18 -0700 From: Jonathan Cavitt To: intel-gfx@lists.freedesktop.org Cc: saurabhg.gupta@intel.com, alex.zuo@intel.com, jonathan.cavitt@intel.com, ville.syrjala@linux.intel.com Subject: [PATCH v2] drm/i915/display: Check some INVALID_TRANSCODER cases Date: Mon, 13 Apr 2026 15:38:19 +0000 Message-ID: <20260413153818.60547-2-jonathan.cavitt@intel.com> X-Mailer: git-send-email 2.43.0 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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" There are some cases in intel_ddi.c, such as in intel_ddi_is_audio_enabled and intel_ddi_compute_config_late, where we attempt to perform a BIT shift using a passed transcoder enum value. This value may be -1, INVALID_TRANSCODER, which can result in undefined behavior if this occurs. In the former case, we can simply return false if this is the transcoder passed (as audio is not enabled on an invalid transcoder). In the latter case, the likely expected behavior is to set the crtc_state->sync_mode_slaves_mask to zero, so just do that directly and avoid a risky bit shift. The likelihood of either case occurring during normal execution is unknown and possibly very low. Regardless, this covers a static analyis issue. v2: Rewrite the latter case to streamline it (Ville) Signed-off-by: Jonathan Cavitt Cc: Ville Syrjälä --- drivers/gpu/drm/i915/display/intel_ddi.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c index 178074316a2c..61d21fcdec95 100644 --- a/drivers/gpu/drm/i915/display/intel_ddi.c +++ b/drivers/gpu/drm/i915/display/intel_ddi.c @@ -3875,7 +3875,8 @@ static void intel_ddi_set_idle_link_train(struct intel_dp *intel_dp, static bool intel_ddi_is_audio_enabled(struct intel_display *display, enum transcoder cpu_transcoder) { - if (cpu_transcoder == TRANSCODER_EDP) + if (cpu_transcoder == TRANSCODER_EDP || + cpu_transcoder == INVALID_TRANSCODER) return false; if (!intel_display_power_is_enabled(display, POWER_DOMAIN_AUDIO_MMIO)) @@ -4636,6 +4637,10 @@ static int intel_ddi_compute_config_late(struct intel_encoder *encoder, crtc_state->master_transcoder = ffs(port_sync_transcoders) - 1; if (crtc_state->master_transcoder == crtc_state->cpu_transcoder) { + if (crtc_state->master_transcoder == INVALID_TRANSCODER) { + crtc_state->sync_mode_slaves_mask = 0; + return 0; + } crtc_state->master_transcoder = INVALID_TRANSCODER; crtc_state->sync_mode_slaves_mask = port_sync_transcoders & ~BIT(crtc_state->cpu_transcoder); -- 2.43.0