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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 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> <20250620182943.GDaFWolxhwogB2tTxb@fat_crate.local> <20250623102105.GCaFkqkatFSbyl1YeN@fat_crate.local> <20250626151837.GFaF1kzfLtesXLqaAQ@fat_crate.local> <20250626160707.GGaF1wK5tW37P6xt0O@fat_crate.local> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 8E18C4000E X-Stat-Signature: wcq6hitcdgo65bns8x5ig77cfqu3gy9k X-Rspam-User: X-HE-Tag: 1750958486-57295 X-HE-Meta: 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 O6FoUZRT W9zMmDCn+DYn6unaoUHS48B0wrNS3UFEEukHuZIBsOsI6aEDpG1XtnFznnQmJh8pNnRpZmrWDkddVebvkuj9pwcdeVWEDMFyuT+lWKAYmWU13tc0RryyiaAbML0zSJH1ZMJbQNvViA9GPIFNQ1HRIpKw7IhdgBR8NAcFHb8uldRC3FuRP0WF5HyWQmXXOvPpsnthNjBBOMZMGBI8BhDZwa65Y26SdM7CC22p3rvdd3Iu0TcBxQiJVqzj5KJNsEbnhzSGuf/41W88GfZf7/1p8F2HlQQ== 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 6/26/25 09:07, Borislav Petkov wrote: >> Makes more sense? > I meant this crap, ofc: > > switch (bug) { > case X86_BUG_CPU_MELTDOWN: > if (boot_cpu_has(X86_FEATURE_PTI)) > return sysfs_emit(buf, "Mitigation: PTI\n"); > > This should say "Mitigation: LASS" if LASS is enabled... > > Which begs the question: how do LASS and PTI interact now? Maybe my babbling about LASS mitigation Meltdown was ill considered. It seems that I've just muddied the waters. All the real LASS-capable hardware also has RDCL_NO=1 which is the _actual_ x86 Meltdown mitigation. Those systems are not vulnerable to Meltdown in the first place. They should say: "Not affected" for Meltdown, both before and after LASS.