From patchwork Mon Jul 15 16:47:21 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Federico Serafini X-Patchwork-Id: 13733652 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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 02E94C3DA62 for ; Mon, 15 Jul 2024 16:47:50 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.759073.1168684 (Exim 4.92) (envelope-from ) id 1sTOrY-0000UE-9L; Mon, 15 Jul 2024 16:47:44 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 759073.1168684; Mon, 15 Jul 2024 16:47:44 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sTOrY-0000TW-3k; Mon, 15 Jul 2024 16:47:44 +0000 Received: by outflank-mailman (input) for mailman id 759073; Mon, 15 Jul 2024 16:47:42 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sTOrW-0006CY-Dl for xen-devel@lists.xenproject.org; Mon, 15 Jul 2024 16:47:42 +0000 Received: from support.bugseng.com (mail.bugseng.com [162.55.131.47]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id f33504ea-42c9-11ef-8776-851b0ebba9a2; Mon, 15 Jul 2024 18:47:40 +0200 (CEST) Received: from truciolo.bugseng.com (unknown [37.163.111.28]) by support.bugseng.com (Postfix) with ESMTPSA id CC5E94EE0739; Mon, 15 Jul 2024 18:47:39 +0200 (CEST) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: f33504ea-42c9-11ef-8776-851b0ebba9a2 From: Federico Serafini To: xen-devel@lists.xenproject.org Cc: consulting@bugseng.com, Federico Serafini Subject: [XEN PATCH v4 8/9] x86/mm: add defensive return Date: Mon, 15 Jul 2024 18:47:21 +0200 Message-Id: X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 Add defensive return statement at the end of an unreachable default case. Other than improve safety, this meets the requirements to deviate a violation of MISRA C Rule 16.3: "An unconditional `break' statement shall terminate every switch-clause". Signed-off-by: Federico Serafini Reviewed-by: Stefano Stabellini --- No changes from v3, further feedback on this thread would be appreciated: https://lists.xenproject.org/archives/html/xen-devel/2024-07/msg00474.html --- xen/arch/x86/mm.c | 1 + 1 file changed, 1 insertion(+) diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c index 648d6dd475..a1e28b3360 100644 --- a/xen/arch/x86/mm.c +++ b/xen/arch/x86/mm.c @@ -916,6 +916,7 @@ get_page_from_l1e( return 0; default: ASSERT_UNREACHABLE(); + return -EPERM; } } else if ( l1f & _PAGE_RW )