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Peter Anvin" Cc: Maciej Wieczor-Retman , tglx@kernel.org, peterz@infradead.org, xin@zytor.com, maciej.wieczor-retman@intel.com, babu.moger@amd.com, chang.seok.bae@intel.com, sohil.mehta@intel.com, dave.hansen@linux.intel.com, jpoimboe@kernel.org, elena.reshetova@intel.com, pawan.kumar.gupta@linux.intel.com, ak@linux.intel.com, darwi@linutronix.de, mingo@redhat.com, x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v11 3/4] x86/cpu: Do a sanity check on required feature bits Message-ID: <20260323205841.GFacGpgZDBOCCG9Y5u@fat_crate.local> References: <7312c9f2feab8aea4612ed9a1841e8c22f5f69b1.1774008873.git.m.wieczorretman@pm.me> <20260323163145.GGacFq8WW0t2uqZm91@fat_crate.local> <207ba0a6-5ebc-465a-8d54-6e5a99622a72@zytor.com> <20260323191905.GDacGSKaG4rEU8O4NA@fat_crate.local> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Mon, Mar 23, 2026 at 01:24:25PM -0700, H. Peter Anvin wrote: > > So what are we really "fixing" here...? > You can make the same argument about #MC for example: why bother trying to get > a message out when the CPU is literally telling you that your system just broke? I don't think you're parsing me right: do you have actual, real-life use cases for which you want this or is this something hypothetical? Because from where I'm standing, this sounds like let's slap another checking function somewhere, we won't hit it ever but just in case, let's be prepared. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette