From patchwork Tue Aug 20 17:09:45 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Stephen Brennan X-Patchwork-Id: 13770495 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) (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 210821BDC8; Tue, 20 Aug 2024 17:10:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=205.220.165.32 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724173842; cv=fail; b=KmZ4TvCXMkkFP+vqEYFMnetX81AuVw2w3dd0lH2+2Gd+Fwf2poElujSSBgIwRM6nIgy5m5US37kxIbgutfaR4CwqTHRrYPU0KuTWOk5+cigQ1XtzDTn+ANB4pDCnSsIRPWp+2BjB6UIVD82nj3FAVORnxGCmBM/UVFwZN6x8KvU= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724173842; c=relaxed/simple; bh=eG3e2AHVgR13OZAIm8dY3cj+a6hNRT/pakDw3xAXl+M=; h=From:To:Cc:Subject:Date:Message-ID:Content-Type:MIME-Version; b=uxE/X8JS2fhZsgFXJLS2zQjFiOgcptkz4qGvMU5SgAdsbNKGm13cQddkayhmkdola3Kd7feksPERInXVqCd2caP3LslwlCs2QdO49ffRPng8wzR2GuXs8SWWivDNEN6Pik0ZchwS41mCldV1fiV5Y0YtvRc7Ubl+OdyytEU9CLE= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oracle.com; spf=pass smtp.mailfrom=oracle.com; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b=CuApNQAX; dkim=pass (1024-bit key) header.d=oracle.onmicrosoft.com header.i=@oracle.onmicrosoft.com header.b=zbSe8Ohi; arc=fail smtp.client-ip=205.220.165.32 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oracle.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oracle.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="CuApNQAX"; dkim=pass (1024-bit key) header.d=oracle.onmicrosoft.com header.i=@oracle.onmicrosoft.com header.b="zbSe8Ohi" Received: from pps.filterd (m0333521.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 47KFBYXr030474; Tue, 20 Aug 2024 17:10:28 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h= from:to:cc:subject:date:message-id:content-type :content-transfer-encoding:mime-version; s=corp-2023-11-20; bh=J J+m7iru5WoiUou3+ysKURV8nzOS2F17np15wwr5L7A=; b=CuApNQAXOLUPz2OhW Hs5LGg00p8SOtFzhh2APJv9LdGA1Stiq9xIJqGUbEfpV31/V2VGQZUwS5HASw+sy /Q0qILgoMK809iEy5xDOuSP7eudbtpVFU1EfkHhLtaVQewUUeJXfOySGDYL9uYys kniAROxYzL0HrpmuUubRLthglhJ1C6RiqmmaFV2obusECt8DScbuT684FVA9Co2i pwcd0TX0k5APltQ9E3QF1qmc2A/zDJkibHMemv/sZ5NCIwjn4U2NuAICBxJQgWFi Hv4IIDujATfNIRtpQ0SlCtOqkEL45eGm4Z7+Gt1mZ5ZqSqljoRH3tOZeEWj9VkEE uaMkw== Received: from iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta03.appoci.oracle.com [130.35.103.27]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 412m45dn2d-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 20 Aug 2024 17:10:27 +0000 (GMT) Received: from pps.filterd (iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 47KG4Hwf024164; Tue, 20 Aug 2024 17:10:26 GMT Received: from nam04-bn8-obe.outbound.protection.outlook.com (mail-bn8nam04lp2047.outbound.protection.outlook.com [104.47.74.47]) by iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 414xbejv8k-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 20 Aug 2024 17:10:26 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=Z8G4Xrlowg/tvwahALPG1TRCtSuyrnWrxohaNftER51HIAgL12O+4c8yMJhBynDAQBuTdTwpMTLW1ISkqvInqcKRyu9NuEJRAnkjKzd58ltMEr9aUOYp4oK04iUpItwQpGoAvPxyv7cTxxsi41yQ54ycJU5FASgWtHSvRPAq9irnQdtophMas7tO3XyjhsZ8m4cMBih9ThgyKPR1oyxCy+T11pp+tvblCmvwXYKrVQaBk+zyZVZ8b3V6vfeS07XegWp4DBdhXq5RWc6gB69h6HsnfVqQqA2LxeS2fCOX0HNsU1mc8bODqfnGnZCZghT/09oFf0cUTAzkdiNYvB7Y4g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=JJ+m7iru5WoiUou3+ysKURV8nzOS2F17np15wwr5L7A=; b=rf7d8QnG6jGJa8t9gTazPZhfZWT/cGu2tXNbMZWvCSpXSlr8c0zb4KZaKnLPYNZn8iDaOryPaVIPQ46jMoaLCvx/DYa916x2ZclQWdC1Tc/mDTvjnNQVQd4w/h+4I3I/IEvyvSNHWysY4O//5gSo3TQJ5QPuqVJxfYdsSY06k13KOa/VttwyuEfgXMfmoENCtLFisFUatB9BBFeKXySa/8J6e61jpH9jk29sqhYLyZWKsY3Q8aeh7z6Eg9sYvPc4U6NQ+UzV3zQLLQBd7YvFxjDaUhDYj9eXEY//3lbJMIiEwasfjfJCVlfcfA0KiKDuwiaruzoJBvCnwLIyyVIOgw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=oracle.com; dmarc=pass action=none header.from=oracle.com; dkim=pass header.d=oracle.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.onmicrosoft.com; s=selector2-oracle-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=JJ+m7iru5WoiUou3+ysKURV8nzOS2F17np15wwr5L7A=; b=zbSe8OhiVgNZq7eZlxfmHnbiPnzb9X0mut3lZ7Es6Saa+smdRduO+dp1Oka/EjDzKWtRBfqIgXNYGS1Ot/Dm0kjgKw92PJ5uxQyIbjAkIxZ7zXkvkygAcHh738HnflgyuXNPnJx1wgZt7YDysLMLRaL0lnrkphUy35CIeZgpFyA= Received: from PH8PR10MB6597.namprd10.prod.outlook.com (2603:10b6:510:226::20) by SA2PR10MB4636.namprd10.prod.outlook.com (2603:10b6:806:11e::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7897.13; Tue, 20 Aug 2024 17:10:24 +0000 Received: from PH8PR10MB6597.namprd10.prod.outlook.com ([fe80::6874:4af6:bf0a:6ca]) by PH8PR10MB6597.namprd10.prod.outlook.com ([fe80::6874:4af6:bf0a:6ca%4]) with mapi id 15.20.7897.010; Tue, 20 Aug 2024 17:10:24 +0000 From: Stephen Brennan To: Masahiro Yamada , Jonathan Corbet Cc: Stephen Brennan , linux-kernel@vger.kernel.org, Nathan Chancellor , linux-doc@vger.kernel.org, linux-kbuild@vger.kernel.org, Nicolas Schier Subject: [PATCH 0/1] Documentation: kbuild: explicitly document missing prompt Date: Tue, 20 Aug 2024 10:09:45 -0700 Message-ID: <20240820171000.1656021-1-stephen.s.brennan@oracle.com> X-Mailer: git-send-email 2.43.5 X-ClientProxiedBy: MN0PR02CA0012.namprd02.prod.outlook.com (2603:10b6:208:530::9) To PH8PR10MB6597.namprd10.prod.outlook.com (2603:10b6:510:226::20) Precedence: bulk X-Mailing-List: linux-kbuild@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH8PR10MB6597:EE_|SA2PR10MB4636:EE_ X-MS-Office365-Filtering-Correlation-Id: 717667b7-eef6-44a4-d923-08dcc13afab5 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|376014; X-Microsoft-Antispam-Message-Info: =?utf-8?q?suM8/c3Sr7HRkMsiiJzStwe2TI4goZy?= =?utf-8?q?0utowa0Pf6/JGjejCysc/WAqRSSAjg81KOREV4p6w0SPc2SY5fFgZFq3YZNADbX4/?= =?utf-8?q?JW/l73XXNWHti1rfrF1Ghgew1/fg7VYrRrQixM5ehIwFGxR85jd9ua1xzCZD3C/uT?= =?utf-8?q?r5apYHkAkW4gTWSWWUuHvuWft5F9aQDWepyVJM7F+efLZY5+SX8JjIFnrnRqtZinZ?= =?utf-8?q?wMiuJMTUr3wZu02kopzz5eGOHINsbGQLrD4QeejbC1P2QwcOrbYM2bNhfXJFeviF0?= =?utf-8?q?wWq0AWMtOcSl/kZQnkrN5svhLFHV63zh+dzzZMM0jWrtfloYwzKak68ZGUYG7Jo7Q?= =?utf-8?q?4oRF2Zva2/zvh74vpH4OTVkTMT2+TmlYS726vBiCIoy1YpVsS3cJpHFl1beu5rpK9?= =?utf-8?q?dnnafnfDLBDqmCqm3sCkE2t+YwKH+yKDhdJ7CCRn4q0BEpqRO/6X8zei4+jLy630k?= =?utf-8?q?MjeESyxWKri162Ma/QrnYKgYr9suKx1EV6JwkR55ZbKPF/DqtakwPljjE3WZ1txdZ?= =?utf-8?q?1UC7JAwvSbW1HWkChn1ZQQkkodQ2srycna1p1UqpNOfjLQZNqJ3MidicXknkB86HF?= =?utf-8?q?btW+BmkARf6oGaVB9uppdXH2x4sXy3/9wy7UEkh5IjUc9h7g1LFJabuQ2dzNjMKA7?= =?utf-8?q?4tVfU6yTtOB4R0Mv1gUysXAKs/JttAVawQtv0EDXcTTCp2CjQAb8JFBwuak+656+F?= =?utf-8?q?wVm1i0nrSewd5TMZp3gtYfK+4xzr2gIA75c1B5VzzBIb4k0xdKhRnhOTg4RB7jAwi?= =?utf-8?q?GOOmN3O6VtJaSEb+KSiMqMeIjhoqMOK82pBkQ2WOGE5jyorGtF7lgQvyzaBotIwNj?= =?utf-8?q?rp/+1MmIgx2Wm7rVGGmHsxT3zcBx4yMrB06YUcWi5wwfRpXSNaNs6B8Rou6T5Exo+?= =?utf-8?q?bY5akSNqzClNCb+78lF32QauLPBSXqh8gqvhLEUbkGfTmknBVR32fb52F+5k+MSng?= =?utf-8?q?ov2mS6rYNVMw9NbFX8n56O3AjCJ8xgPJjZu0qjLcsXRXppAuV09LXRn7XVxe8VOLC?= =?utf-8?q?pfMoT4m4gwpsIfzreGmcvpwKQ7mJ0RCQ/4mkMxCJmT4C996SW0HdTPUbDI5rFCnCt?= =?utf-8?q?w9xjzzwBKq4YZ74YtkZ9srJzbhecA31Rh1bx/kaf3Xndpj7+XwZOzghLcZ8xeKdj8?= =?utf-8?q?ajvCDRw7mOWGY+fQWKNXRE4TG00qXgrvQtf2AgRqVfF0aoULT3kPf2+6NE+MgbT0O?= =?utf-8?q?BEBlM/FUN9V0UI/jw0fU0JwGgYr753m6L3yV6OP4iJ3ioaSdWmKwU/OqCYzVHSSRR?= =?utf-8?q?0i5c5eAH8rr/ZDiJoWCAgBouhQhuFjhUe6A=3D=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:PH8PR10MB6597.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(1800799024)(376014);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?q?Qq01k3PKbYYD7XAUxAOInGZuIV0a?= =?utf-8?q?1z0rAleMAhe7UAdUPNkat4HQS1xpE8AB9vgWvhof9GUAL0liknLvq0hcYDjH8j55F?= =?utf-8?q?QHo/VimEsHndMpBa0uvXkgZ3TrNE2EwpxbiHGJlxh5J/vXLuuT/rYai2T1RUQlpFA?= =?utf-8?q?rQoQPimbGA0xuOFVji78G696Swj03wO3V3h35fyDqrcekIF9swoC/LYLTCOlKOJqH?= =?utf-8?q?E2gfq1AzqXUKxEkAgLfEGh+vo/6jdVCuUlFGEVHPhLdsTNvxUlYTxQkZ8G1usgY8G?= =?utf-8?q?Qr+pHiaKYOZGi4vBaphovThlv2xgbiT+rVZMDhpSe1TJOt/V9RzqPXEYmCmNKyn3n?= =?utf-8?q?j2CTwDoBen5j1z6Hee/ZdkuGDK8z0lA/67nfMVULG+L10GVL1JSLZgvwZ1MEpYbpK?= =?utf-8?q?rIUzRqVk10bTRSKp2ZhJakvGnFnRclHywsbGNVWuQDY+l283T9xpRn/rdYhVa2CQF?= =?utf-8?q?QccLBulUbyOl9qIstehfsaqUCm7rRefyVSXozFNBVD3THeW/W3CgwgH/awFs6m6VJ?= =?utf-8?q?qx0pCXng69O8K4mtCxYjUX+jGkExcCx2cR9aXDX9SvGNIp5s9QmLGXjq1H1lwTzil?= =?utf-8?q?u/Lq0mXzG3tmbWVFMkzWVrsxUP4E2LwNiSM844yXr6aGtEWwtGYUTRWfAo24Vb7RD?= =?utf-8?q?ohIXae7u35dozIazXrgPSacx0Uzrhu9vCsSVWYgWo7PknwBPRqeR60fGPibeZox2J?= =?utf-8?q?MBwkDJnwxAvs5Vf7taC8U7aphULHEbBWcX/7y87u5RssolMJUan/xPwFsYEe2vfxB?= =?utf-8?q?dNuhB9Ft5Q2cfpsOtr/wmWoNFac1+NKcOHZ/PL6ozztQHc7C1nnCNj39Fr3GNjUqv?= =?utf-8?q?CtwjiGNYs+n1mN+6rXAGzbcqj9kclQuObxEmTeOB3NUG/KkZFIJwEzbBzvQ1vQuSN?= =?utf-8?q?YoVWs7E3LhMQH2g8qmcd9jI/M0O/dwnVX/1X8Y3P1F5Xu2UXwc5jOIu/1KlcFLOha?= =?utf-8?q?shC9r96fC0zSlG3ihJSB7WYcS9ZvUJbPNMjPs0IMKOu35J6FhEgDr64WDvnUYwLxG?= =?utf-8?q?Z7bYje80rlU1ycqEE8lPicWohx2ySJPtkZ+bInSc27IgLdyg8RLEalW5ap2X+lRHq?= =?utf-8?q?4WFmWs/nePcW648iLnH30PdIjb30QP4cVHUbNQGH862ag4Xj05UJGvFh7IBy7OmQL?= =?utf-8?q?+DqYn9OUNnST/tz82FUZO6opi2WLHXFX8rQjV2vfECwT1jWbirYdOidhM/l+CJp+a?= =?utf-8?q?2td4MDZUMQM5elRBxVAsAvy02Y4GJSEI9flmz9FyC4JNWSM93D5huoEJ7HPRK3E9x?= =?utf-8?q?xLjnimloyi3gEjYEEylbEDSKht/6wF4ICp+NXQ/NdnlT87tTTOJ0decbVEYJ4RuMA?= =?utf-8?q?G1EWjRG5KGqa1qDk8r+kMF6TkXKVk4ZFWEvYqkK+uu/pj+uPSIt70OjOF5eBWLWSd?= =?utf-8?q?4hyEJg27aDbV/BVArEa81FDkZaijnqezK+bu2EsKfkGHc3PEEpGPKUY10AczucDKX?= =?utf-8?q?n43yNkqhwh91Hf2j0NcQa6bmOy78cQBSTx//hFIKzUb/xIHz9En5MV39lkUqNinoU?= =?utf-8?q?IFVqxMGqGTTtnoObMwBjrF3SQznd+kOsYw=3D=3D?= X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: 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 X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: 717667b7-eef6-44a4-d923-08dcc13afab5 X-MS-Exchange-CrossTenant-AuthSource: PH8PR10MB6597.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Aug 2024 17:10:23.9475 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: ESpuKzXUUWTfGz55xiH7N3q4O5fcSJ3hjAJwF0a+Fb+A2OuQ1PLE8N6wY4OcZrKEO5cB5shYOfzuyc+CA/mLI3Zr+e4H4sphhsHpwB6WCok= X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA2PR10MB4636 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.680,FMLib:17.12.28.16 definitions=2024-08-20_12,2024-08-19_03,2024-05-17_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 spamscore=0 malwarescore=0 mlxscore=0 bulkscore=0 suspectscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2407110000 definitions=main-2408200128 X-Proofpoint-ORIG-GUID: 4eYLwodDbdjBhRU-UDlTU-E34WIdFxdE X-Proofpoint-GUID: 4eYLwodDbdjBhRU-UDlTU-E34WIdFxdE Hi folks, Recently I was trying to build a kernel with the following options: CONFIG_KALLSYMS_ABSOLUTE_PERCPU=n CONFIG_KALLSYMS_BASE_RELATIVE=n They are defined in init/Kconfig like so: config KALLSYMS_ABSOLUTE_PERCPU bool depends on KALLSYMS default X86_64 && SMP config KALLSYMS_BASE_RELATIVE bool depends on KALLSYMS default y I was banging my head against the wall trying to understand why I couldn't edit these with any kconfig tool (e.g. make xconfig) and why my edits to the .config file were getting overwritten. A coworker finally explained to me that the reason was that the config options did not have a prompt, and so they are not user configurable. This is a really subtle behavior that was not obvious to me from the documentation. Though now I understand it, I can see why it's used widely. For example, KALLSYMS_ABSOLUTE_PERCPU has no prompt and is only set when X86_64 && SMP, because it is a trick that allows percpu variables to be encoded while still only using 32 bits to encode each address. This approach requires treating the 32-bit value as signed, which limits the range of addresses that could be encoded in other situations for other architectures, so it is implemented as a config option that is selected only where necessary: very clever. Since this is real behavior that's used for real purposes, let's document it here. I could only find oblique references in the document regarding config entries without prompts: - Describing the "visible" keyword: "It is similar to a conditional “prompt” attribute for individual menu entries." This implies preexisting knowledge about prompts that was never explained. - Describing the select keyword: "In general use select only for non-visible symbols (no prompts anywhere) and for symbols with no dependencies." This does spell out that symbols become invisible without prompts, but it's in an unrelated spot where a reader wouldn't expect to find it. It also isn't clear that "invisible" symbols can't even be altered by tweaking ".config". - Describing the default keyword: "If an input prompt is visible the default value is presented to the user and can be overridden by him." This doesn't state anything about a missing prompt, though maybe it invites the reader to assume the inverse, if a prompt is not set, the value cannot be overridden. Thanks, Stephen Stephen Brennan (1): Documentation: kbuild: explicitly document missing prompt Documentation/kbuild/kconfig-language.rst | 3 +++ 1 file changed, 3 insertions(+)