From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.11]) (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 E16CE3783B5; Tue, 6 Oct 2026 18:30:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791311457; cv=none; b=hb3wmE7x9hK2adhFumGkViYcXF93w3pKPLswPStvkfHosL9yNKzSyuzyCi/bqpOY6dZ8u5WqVHXJV3jTG/q+39Vqeb18xOvj4sQUeRMlye2O7uuHLYkOOidDiuIvZRy/eB1mOamV1wzbFTsGnQPderRxyb0YmiEf6v0+fIwIffs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791311457; c=relaxed/simple; bh=R6dsZrhu9NgBwhhSFSnog9rmIHrIC0UuWb7KJIsDK+E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=m6t1qsPDEogOMu7FifhX0AasJfHC1BFID5wC0wCS+w2FeAXiwu0Tb572DoHVuscGcJfdNodt/K7EdwFscxFeJR5lwBAL0fjyRYoa5/tIF2Ktz2+LbmLOPjY37Ry+3AeD2udEFwW6M/0qtWnkwkQIGtS/qsWMTYwHjbH0gmplGPk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=aU2E0M4c; arc=none smtp.client-ip=192.198.163.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="aU2E0M4c" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1791311456; x=1822847456; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=R6dsZrhu9NgBwhhSFSnog9rmIHrIC0UuWb7KJIsDK+E=; b=aU2E0M4cbCn+294gJQk/XZPlxbaoGFCciv2McmagGD1aWayPwd2l/rJs tzHTUIU9XdckgoSTIm8/AFbFUz0ygeh7p3Zd03fQ22npyQXAAN+yi3Kla ho9hmecoNHSTZyk8cwqVhFSnPb1zf8PRDSOKWaW3rjUhVq9SyqbPaaklg NvgTpL/1u1kUFT+R/FSHWUlnvvzgcLlwr7L15V08Y73TbrZk3hXGz+ZMT NSSZY6QlfbwT2JVLzelKySjQizEn+MzNbHDgywnZvIRHdBv9JEIJ7OtHk D7Mq7Mh4zViRELU0Vu3BSuXlJP5qELFE7PIlj2uW7YhGjKxnCcJZyU7RT Q==; X-CSE-ConnectionGUID: txGAGQjDQx2D2hz7nXw26A== X-CSE-MsgGUID: iPPlm/fyRYGfTwsNUxMe8g== X-IronPort-AV: E=McAfee;i="6800,10657,11927"; a="102591586" X-IronPort-AV: E=Sophos;i="6.27,143,1787036400"; d="scan'208";a="102591586" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by fmvoesa105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Oct 2026 11:30:54 -0700 X-CSE-ConnectionGUID: YVCBaCMkS1K4N70mgbxNXQ== X-CSE-MsgGUID: dpPy3Ff7RNuwe/7KHRaghA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,143,1787036400"; d="scan'208";a="303500246" Received: from skuppusw-desk2.jf.intel.com ([10.165.154.101]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Oct 2026 11:30:54 -0700 From: Kuppuswamy Sathyanarayanan To: Srinivas Pandruvada , Hans de Goede , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , David E Box Cc: Andy Shevchenko , platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 01/20] platform/x86/intel/tpmi: Use static strings for the feature device names Date: Tue, 6 Oct 2026 11:30:18 -0700 Message-ID: <20261006183037.1507007-2-sathyanarayanan.kuppuswamy@linux.intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20261006183037.1507007-1-sathyanarayanan.kuppuswamy@linux.intel.com> References: <20261006183037.1507007-1-sathyanarayanan.kuppuswamy@linux.intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit tpmi_create_device() builds the auxiliary device name in an on-stack buffer and hands it to intel_vsec_add_aux(), which stores the pointer in auxdev->name without copying the string. The auxiliary device outlives tpmi_create_device(), so auxdev->name is left pointing into a stack frame that has already been torn down. Nothing dereferences auxdev->name after intel_vsec_add_aux() returns today: auxiliary_device_init() only checks it for NULL and both dev_set_name() calls copy into dev->kobj.name, while driver matching and the modalias use dev_name() instead. So this is a latent problem rather than a live one, but the auxiliary bus expects the name to outlive the device, and the other intel_vsec_add_aux() caller already passes a string literal. Convert intel_tpmi_name() into a lookup of a static array of string literals that already include the "tpmi-" prefix, and pass its return value straight to intel_vsec_add_aux(). Using a static array instead of a switch statement makes the lifetime of the returned strings obvious: they are valid for as long as the module is loaded. The snprintf() along with its on-stack buffer and length define are no longer needed. The resulting device names are unchanged, so the feature drivers keep matching on "intel_vsec.tpmi-" as before. No functional change intended. Reviewed-by: Andy Shevchenko Reviewed-by: Srinivas Pandruvada Signed-off-by: Kuppuswamy Sathyanarayanan --- drivers/platform/x86/intel/vsec_tpmi.c | 41 +++++++++++++------------- 1 file changed, 20 insertions(+), 21 deletions(-) diff --git a/drivers/platform/x86/intel/vsec_tpmi.c b/drivers/platform/x86/intel/vsec_tpmi.c index 0153dd57838e..9b2bd0c8cbe2 100644 --- a/drivers/platform/x86/intel/vsec_tpmi.c +++ b/drivers/platform/x86/intel/vsec_tpmi.c @@ -47,6 +47,7 @@ */ #include +#include #include #include #include @@ -579,33 +580,31 @@ static void tpmi_set_control_base(struct auxiliary_device *auxdev, tpmi_info->tpmi_control_mem = mem; } +/* + * The TPMI IDs are sparse, so the unused entries are left NULL and are + * rejected by the caller like any other unsupported feature. + */ +static const char * const intel_tpmi_names[] = { + [TPMI_ID_RAPL] = "tpmi-rapl", + [TPMI_ID_PEM] = "tpmi-pem", + [TPMI_ID_UNCORE] = "tpmi-uncore", + [TPMI_ID_SST] = "tpmi-sst", + [TPMI_ID_PLR] = "tpmi-plr", +}; + static const char *intel_tpmi_name(enum intel_tpmi_id id) { - switch (id) { - case TPMI_ID_RAPL: - return "rapl"; - case TPMI_ID_PEM: - return "pem"; - case TPMI_ID_UNCORE: - return "uncore"; - case TPMI_ID_SST: - return "sst"; - case TPMI_ID_PLR: - return "plr"; - default: + if (id >= ARRAY_SIZE(intel_tpmi_names)) return NULL; - } -} -/* String Length for tpmi-"feature_name(upto 8 bytes)" */ -#define TPMI_FEATURE_NAME_LEN 14 + return intel_tpmi_names[id]; +} static int tpmi_create_device(struct intel_tpmi_info *tpmi_info, struct intel_tpmi_pm_feature *pfs, u64 pfs_start) { struct intel_vsec_device *vsec_dev = tpmi_info->vsec_dev; - char feature_id_name[TPMI_FEATURE_NAME_LEN]; struct intel_vsec_device *feature_vsec_dev; struct tpmi_feature_state feature_state; struct resource *res, *tmp; @@ -634,8 +633,6 @@ static int tpmi_create_device(struct intel_tpmi_info *tpmi_info, feature_vsec_dev->num_resources = pfs->pfs_header.num_entries; res = feature_vsec_dev->resource; - snprintf(feature_id_name, sizeof(feature_id_name), "tpmi-%s", name); - for (i = 0, tmp = res; i < pfs->pfs_header.num_entries; i++, tmp++) { u64 entry_size_bytes = pfs->pfs_header.entry_size * sizeof(u32); @@ -654,9 +651,11 @@ static int tpmi_create_device(struct intel_tpmi_info *tpmi_info, * delete is required on error or on module unload. * feature_vsec_dev and res memory are also freed as part of * device deletion. + * + * "name" must outlive the auxiliary device, as the auxiliary bus + * stores the pointer rather than a copy of the string. */ - return intel_vsec_add_aux(&vsec_dev->auxdev.dev, - feature_vsec_dev, feature_id_name); + return intel_vsec_add_aux(&vsec_dev->auxdev.dev, feature_vsec_dev, name); } static int tpmi_create_devices(struct intel_tpmi_info *tpmi_info) -- 2.43.0