From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gustavo A. R. Silva" Subject: [PATCH] ACPI / CPPC: Use 64-bit arithmetic instead of 32-bit Date: Tue, 6 Feb 2018 17:36:17 -0600 Message-ID: <20180206233617.GA30829@embeddedgus> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from gateway24.websitewelcome.com ([192.185.50.66]:23713 "EHLO gateway24.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753862AbeBFXgT (ORCPT ); Tue, 6 Feb 2018 18:36:19 -0500 Received: from cm14.websitewelcome.com (cm14.websitewelcome.com [100.42.49.7]) by gateway24.websitewelcome.com (Postfix) with ESMTP id BBB271B7B8 for ; Tue, 6 Feb 2018 17:36:18 -0600 (CST) Content-Disposition: inline Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Rafael J. Wysocki" , Len Brown Cc: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Add suffix ULL to constant 500 in order to give the compiler complete information about the proper arithmetic to use. Notice that this constant is used in a context that expects an expression of type u64 (64 bits, unsigned). The expression NUM_RETRIES * cppc_ss->latency at line 578, which at preprocessing time translates to 500 * cppc_ss->latency is currently being evaluated using 32-bit arithmetic. Addresses-Coverity-ID: 1382602 Signed-off-by: Gustavo A. R. Silva --- Notice that another option is to cast NUM_RETRIES to u64 at line 578, but as there is only one instace in which this macro is being used I think adding the ULL is just enough. drivers/acpi/cppc_acpi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 06ea474..0afbb26 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -119,7 +119,7 @@ static DEFINE_PER_CPU(struct cpc_desc *, cpc_desc_ptr); * to PCC commands. Keeping it high enough to cover emulators where * the processors run painfully slow. */ -#define NUM_RETRIES 500 +#define NUM_RETRIES 500ULL struct cppc_attr { struct attribute attr; -- 2.7.4