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Fri, 1 Apr 2022 20:27:05 +0000 Received: from SA1PR10MB5866.namprd10.prod.outlook.com ([fe80::25e3:38e5:fb02:34c1]) by SA1PR10MB5866.namprd10.prod.outlook.com ([fe80::25e3:38e5:fb02:34c1%5]) with mapi id 15.20.5123.026; Fri, 1 Apr 2022 20:27:05 +0000 From: Alejandro Jimenez To: corbet@lwn.net, mcgrof@kernel.org, keescook@chromium.org, yzaikin@google.com, linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Cc: akpm@linux-foundation.org, linux@rasmusvillemoes.dk, ebiggers@google.com, peterz@infradead.org, ying.huang@intel.com, gpiccoli@igalia.com, mchehab+huawei@kernel.org, Jason@zx2c4.com, daniel@iogearbox.net, robh@kernel.org, wangqing@vivo.com, prestwoj@gmail.com, dsahern@kernel.org, stephen.s.brennan@oracle.com, alejandro.j.jimenez@oracle.com Subject: [RFC 0/1] Add sysctl entry for controlling crash_kexec_post_notifiers Date: Fri, 1 Apr 2022 16:22:59 -0400 Message-Id: <20220401202300.12660-1-alejandro.j.jimenez@oracle.com> X-Mailer: git-send-email 2.34.1 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: DM5PR07CA0083.namprd07.prod.outlook.com (2603:10b6:4:ad::48) To SA1PR10MB5866.namprd10.prod.outlook.com (2603:10b6:806:22b::19) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: f02fd156-e53c-4d6f-fc9b-08da141dfc76 X-MS-TrafficTypeDiagnostic: SJ0PR10MB5647:EE_ X-Microsoft-Antispam-PRVS: X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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I am aware that because it is a kernel core parameter, there is already an entry under: /sys/module/kernel/parameters/crash_kexec_post_notifiers and that allows us to read/modify it at runtime. However, I thought it should also be available via sysctl, since users that want to read/set this value at runtime might look there first. I believe there is an ongoing effort to clean up kernel/sysctl.c, but it wasn't clear to me if this entry (and perhaps the other panic related entries too) should be placed on kernel/panic.c. I wanted to verify first that this change would be welcomed before doing additional refactoring work. I'd appreciate any comments or suggestions. Thank you, Alejandro Alejandro Jimenez (1): kernel/sysctl: Add sysctl entry for crash_kexec_post_notifiers Documentation/admin-guide/sysctl/kernel.rst | 8 ++++++++ include/uapi/linux/sysctl.h | 1 + kernel/sysctl.c | 7 +++++++ 3 files changed, 16 insertions(+) -- 2.34.1