From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.zytor.com (terminus.zytor.com [198.137.202.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7D2632264CF for ; Fri, 13 Feb 2026 20:17:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.136 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771013857; cv=none; b=hoK9GT67vq+1uDZeJxSqyALy8AJ6NAPJFbYJhmJrCYG0LkttXodx2SEMK/Vj29UtSNmOaZGk3w9FIRfYB9/k/5pNFUfRuHkeuw2r5jAudy9hy9LKg8S4silJ2gsFE0dgTB//KP2dZcFAJ8df0L7q4kzkurqRS0LwRKQjnfprIy0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771013857; c=relaxed/simple; bh=d7M9UVdG0yrd/fdxNYthcElWDttC+o939N4xU/R/YrY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=nx3EHAAl2VNT5V4lOQpKqC4Erq+SBi9HI6XLxI6PNWOT4xY+TcYmilatbPYYAhNC3uOVsRMjG22SySoqzHukag0rP96XwCUW3M2CCDF4nPEblPfg7azFzeBrA3GE75cniFYVAQncneu1mNBW1f8PZFjpWdByVW6Lfi7AgrU5Te0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zytor.com; spf=pass smtp.mailfrom=zytor.com; dkim=pass (2048-bit key) header.d=zytor.com header.i=@zytor.com header.b=gNTrXf8P; arc=none smtp.client-ip=198.137.202.136 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zytor.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=zytor.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=zytor.com header.i=@zytor.com header.b="gNTrXf8P" Received: from [IPV6:2607:fb90:3709:ce04:bf4c:86df:148a:f3f5] ([IPv6:2607:fb90:3709:ce04:bf4c:86df:148a:f3f5]) (authenticated bits=0) by mail.zytor.com (8.18.1/8.17.1) with ESMTPSA id 61DKH4vX951784 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO); Fri, 13 Feb 2026 12:17:06 -0800 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.zytor.com 61DKH4vX951784 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2026012301; t=1771013828; bh=pu8Vz5bjvgi7cDkXWWO0Zz6SWSM0C/NAqbeZ0LRqTlA=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=gNTrXf8PlrTw4mzeBi8yLsidDGagn6WSW4EydkguBsvwVjHKXCS1VqGD67XAxfwDD w3cwMapy+gweEuxHcvIMnTADBw5CEAHF1YiPVlsD0jxV6LR5PJ4xpt77FrXb7jMcKL S2d8tLDSnxBB2/ciHA+2bXZooXtp1FmdEhUGTNhPmX2m+bYmI6da43/Vz4Y7jEN662 vdnVe/rHwGrzeaYZdjRg9RI8rYXnKXwDZJElNec5sFHkydJ/TEEKWBlwx1TY+7scdt TFwd/6yaVK2h+dkry6JOm6ptMScT4jsZcYubKziKIeuvK17kuVBHhJtGUBksv92Hzn SnoJTaBet93nQ== Message-ID: <5fd597a1-46fe-4f46-98ee-d346260c85b5@zytor.com> Date: Fri, 13 Feb 2026 12:17:02 -0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 3/3] x86/cpu: Required feature bits sanity check To: Maciej Wieczor-Retman , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org Cc: pawel.chmielewski@linux.intel.com, Maciej Wieczor-Retman , linux-kernel@vger.kernel.org References: <1bfbcdf7d2d7d5a1180e0de92d14cd6c246d5ea5.1770908783.git.m.wieczorretman@pm.me> Content-Language: en-US, sv-SE From: "H. Peter Anvin" In-Reply-To: <1bfbcdf7d2d7d5a1180e0de92d14cd6c246d5ea5.1770908783.git.m.wieczorretman@pm.me> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 2026-02-12 07:35, Maciej Wieczor-Retman wrote: > From: Maciej Wieczor-Retman > > After cpu identification concludes, do a sanity check by comparing the > final x86_capability bitmask with the pre-defined required feature bits. > > Signed-off-by: Maciej Wieczor-Retman For as much as it matters (since I originally requested Maciej implemented this): Acked-by: H. Peter Anvin (Intel) We really, really need this. We have this check in the BIOS boot stub, but none of the modern stubs have included the equivalent code. -hpa