From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=198.175.65.16 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793676865; b=rdNJ+rEYrTeq3+nbUYdsjoWC4FOWnU//pnCRWTtiptvZPWIJvJd9iWhR5eSkm28f8j0V cdqip6YM2KwMXg0dhUQQexEI5jAdrVsuHCFIYegcR8g3zqE68piAHXdgqZ73Beo5QKm+T 3rMVkYsQDi2srr1ZsNS5KJCax6mSs2mVrTkqnwBJrMEEuUJhrW0G+9IqHZZ0jj2TJVnwq wylxeLE3Tz0/B4xZg7aUCmTdTMeUrGxX/5wYRP3vI/gM5dGyrCxDBhFGky3cCcEvAKfd5 yy+KiRLcsEIHTiqUfBwFbRBGk1mcSBcs4mhzUBXL/n+K4TJ8vigJMPvmnGUes3N2rHQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793676865; h=DMARC-Filter:DKIM-Signature:X-CSE-ConnectionGUID:X-CSE-MsgGUID: X-IronPort-AV:X-IronPort-AV:Received:X-CSE-ConnectionGUID: X-CSE-MsgGUID:X-ExtLoop1:X-IronPort-AV:Received:From:To:Cc:Subject: Date:Message-ID:X-Mailer:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding; bh=3PzSXFuZlMlTOfUVklWCQpzN4rvz3ZOn5hMVSUTf87Y=; b=TSkMfV3wzfeatajfIWcIxmyasSxNUyJoFLxbbeRO2xOUtgXpNZMUdXHFSD6OmMc3016b 2hCYhxiDLyFo0rBEhB6FXGJ4vOqWtBv2H8elV/1T5VNK+4/AtiO7wmv0piNwklK0EIp+t QP+hlRI3cBm+bZHoxpa4+ot06ojEVb+7+pASKd5D56bWTbhSFUlKHUgavcgvn0VS0AM+Q kPjXHd6RyRBNrUZl4W23aKuzpGYCKnCVcmmO03y6qsbw2Y35FLhuDY8LJqQC4+DvubZTB 3+AAQBPaG0mSLsJS51ATdYa4QXye5eQfdlnbsIySYY4Zt1PijODKBdCURPoMBoU0p3A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=cXsaPy4H; arc=none smtp.remote-ip=198.175.65.16 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.16]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EDF4E606D805 for ; Tue, 3 Nov 2026 03:34:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org EDF4E606D805 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=cXsaPy4H DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1793676864; x=1825212864; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=2ibaC0LwI4fMdA38nqhEQ20mlW1BgDPT1XXy0q2NaVg=; b=cXsaPy4HAb4g0tCwkgHdYj3Kt42tgy+Am1ertOZXy2SI84I83PosGD2m ov8G+xQzgC4fO44YDdoJ8E0Y2ksfQe991AgbnM/UyRnGLahzk3N9jMDQc OZrYjbgd4SmCW9x81c8JZ5lGpjOrbyS9OvivKFQVWVvnNzbqDgb9xGwXo ChG4NO3u3PMz3sYWiFQ9Ctcpabc+y08XoNJ1Xg+8PRUv25vOkEweOmq+T jw0vktMvBCSP+Kk+9PkXRdemdMInYQH53WETelI0ZHwkkPL5deqY22IiM 1kDs8umUVb0M96lT/fE1q7rr3Or/AoPFnIqRjCAjFAveFBvhWDBYlZ4Uo Q==; X-CSE-ConnectionGUID: x0cPM0eXT3e8SKeXsBovVA== X-CSE-MsgGUID: /2H+7++SRUim0yoX79DNfQ== X-IronPort-AV: E=McAfee;i="6800,10657,11954"; a="2380797" X-IronPort-AV: E=Sophos;i="6.27,192,1787036400"; d="scan'208";a="2380797" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by orvoesa108.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Nov 2026 19:34:23 -0800 X-CSE-ConnectionGUID: aUffzQs6T5y2KTInS4KtZA== X-CSE-MsgGUID: ZSxTTBwISoCaBhdgtP3ijA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,192,1787036400"; d="scan'208";a="6159869" Received: from junxiao.bj.intel.com ([10.238.152.95]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Nov 2026 19:34:20 -0800 From: Junxiao Chang To: jani.nikula@linux.intel.com, rodrigo.vivi@intel.com, matthew.brost@intel.com, thomas.hellstrom@linux.intel.com, airlied@gmail.com, simona@ffwll.ch, bigeasy@linutronix.de, clrkwllms@kernel.org, rostedt@goodmis.org, intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev Cc: dev@lankhorst.se, junxiao.chang@intel.com Subject: [PATCH 2/2] drm/xe/gsc: warn about GSC stolen memory usage on RT kernels Date: Wed, 4 Nov 2026 11:27:32 +0800 Message-ID: <20261104032732.30681-3-junxiao.chang@intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20261104032732.30681-1-junxiao.chang@intel.com> References: <20261104032732.30681-1-junxiao.chang@intel.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The GSC microcontroller requires stolen memory, which can introduce latency spikes and negatively impact real-time performance. Print a warning on CONFIG_PREEMPT_RT kernels to inform the user that GSC is active and that RT performance can be improved by disabling the GSC firmware (e.g., by setting the module parameter xe.gsc_firmware_path=""). Signed-off-by: Junxiao Chang --- drivers/gpu/drm/xe/xe_gsc.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/xe/xe_gsc.c b/drivers/gpu/drm/xe/xe_gsc.c index aab59dc647fbd..3d06ab6fecbe0 100644 --- a/drivers/gpu/drm/xe/xe_gsc.c +++ b/drivers/gpu/drm/xe/xe_gsc.c @@ -427,6 +427,11 @@ int xe_gsc_init(struct xe_gsc *gsc) else if (ret) goto out; + if (IS_ENABLED(CONFIG_PREEMPT_RT)) { + xe_gt_warn(gt, "RT performance might be impacted by GSC stolen memory usage\n"); + xe_gt_warn(gt, "Consider disabling GSC (xe.gsc_firmware_path=\"\") to improve it\n"); + } + ret = xe_gsc_proxy_init(gsc); if (ret && ret != -ENODEV) goto out; -- 2.43.0