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Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.2.2 Subject: Re: [PATCH v2] mm: Make failslab writable again To: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Jonathan Corbet , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Vlastimil Babka , Roman Gushchin , kernel@openvz.org, Kees Cook , Roman Gushchin , Jann Horn , Vijayanand Jitta , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <20220920121111.1792905-1-alexander.atanasov@virtuozzo.com> From: Alexander Atanasov In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: VI1PR07CA0252.eurprd07.prod.outlook.com (2603:10a6:803:b4::19) To VE1PR08MB4765.eurprd08.prod.outlook.com (2603:10a6:802:a5::16) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: VE1PR08MB4765:EE_|GV1PR08MB7803:EE_ X-MS-Office365-Filtering-Correlation-Id: 50ff07b1-44c9-47fc-f308-08da9d360d91 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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And you need to >> set atleast one more option to trigger fault injection. >> - in a testing scenario you may need to change it at runtime >> example: module loading - you test all allocations limited >> by the space option. Then you move to test only your module's >> own slabs. >> - when set by command line flags it effectively disables all >> cache merges. > > Maybe we can make failslab= boot parameter to consider cache filtering? > > With that, just pass something like this: > failslab=X,X,X,X,cache_filter slub_debug=A,> > Users should pass slub_debug=A, anyway to prevent cache merging. It will be good to have this in case you want to test cache that is used early. But why push something to command line option only when it can be changed at runtime? -- Regards, Alexander Atanasov