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Shutemov" Cc: Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Peter Zijlstra , Ard Biesheuvel , "Paul E. McKenney" , Josh Poimboeuf , Xiongwei Song , Xin Li , "Mike Rapoport (IBM)" , Brijesh Singh , Michael Roth , Tony Luck , Alexey Kardashevskiy , Alexander Shishkin , Jonathan Corbet , Sohil Mehta , Ingo Molnar , Pawan Gupta , Daniel Sneddon , Kai Huang , Sandipan Das , Breno Leitao , Rick Edgecombe , Alexei Starovoitov , Hou Tao , Juergen Gross , Vegard Nossum , Kees Cook , Eric Biggers , Jason Gunthorpe , "Masami Hiramatsu (Google)" , Andrew Morton , Luis Chamberlain , Yuntao Wang , Rasmus Villemoes , Christophe Leroy , Tejun Heo , Changbin Du , Huang Shijie , Geert Uytterhoeven , Namhyung Kim , Arnaldo Carvalho de Melo , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, linux-mm@kvack.org, Yian Chen Subject: Re: [PATCHv6 01/16] x86/cpu: Enumerate the LASS feature bits Message-ID: <20250620182943.GDaFWolxhwogB2tTxb@fat_crate.local> References: <20250620135325.3300848-1-kirill.shutemov@linux.intel.com> <20250620135325.3300848-2-kirill.shutemov@linux.intel.com> <20250620163504.GCaFWNuI-8QFqAM0yI@fat_crate.local> <6y2iqv6c2idn7yebaec7tyhzl5zcsrwqq4lcsokumlqeophzaf@ljnmxorblgcj> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <6y2iqv6c2idn7yebaec7tyhzl5zcsrwqq4lcsokumlqeophzaf@ljnmxorblgcj> X-Rspam-User: X-Stat-Signature: bcj6dcf9mc9c8usz9c333y5imqagn8yi X-Rspamd-Queue-Id: 39697C000F X-Rspamd-Server: rspam02 X-HE-Tag: 1750444248-683243 X-HE-Meta: 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 SMNRKzws A4n2gMy2TInHc9rgUhzt85kCIg4QUfcE9dPiz8gEOcv5fa9VZd4FWZ5tC5FE05e35r27zR56YUMF3NxReWGRvqQLRBjQ/W22Xt/a7DoGfguEyE1mcJdgHoDLnhDAs2TdJ5f0Ud4QdFNjfXBagAjJAVBTi7muaaoepgMJiziETOJqVn8QMUlPvcW5L6EERFfuCodJ8xhMOy5AveudX0n4zLD/Xw2x1MquataF67q8n/sh0C5rRPSyUGRXvV1wUiuieXiRJ57cp9xqr3vAq4TQdoSWp1kEU4QUFcaMlD9nNjQzmu5Ulp7FcprNCvBZP22j3jtfhMFZ28/RXSukR7kaW+qSYmjws/oukYcOs6jdbPPZfNDKVKT4N7TvZoA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Jun 20, 2025 at 08:33:36PM +0300, Kirill A. Shutemov wrote: > What is current policy around it ? Documentation/arch/x86/cpuinfo.rst > I think it is useful to advertise security features in cpuinfo. Because who's going to consume them? Don't get me wrong - I am trying to see whether the whole use case for this is well thought out. Because it becomes an ABI. But if no one is going to use it, why bother? Arguably, for this thing the argument would be - as it is put in that file above: "So, the current use of /proc/cpuinfo is to show features which the kernel has *enabled* and *supports*." as it has been enabled by machinery. So that's ok. I'm just making sure we're on the same page and you're not aiming at something completely different with this. Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette