From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2A282184540 for ; Fri, 23 Jan 2026 17:55:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769190914; cv=none; b=NhsUyD2N3/0WGdtR/2sz96hIC82BHlUm4/ROAJyKdoE2C2S6qlph2Arbav3Xem6S6zCFDzxmMJMpjdrrMwTnl9h2cXmAilKViN8nub3+O+fCrS47L/vWkig05+idWfbVhBL2fP07Ag2zjPSbrW9KfkpOW3DLcw01Pwe8Kb9mQ+U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769190914; c=relaxed/simple; bh=zXAJgkPE1pPkpAeSf54sl9gNOz+zUWSoNtaXn7i4ovI=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=cJEJ29EguC+daxaDaq4gXl4rLwk6bT82ZTWT8Fe8vcOWfkGHn/kvTieMBs1y0+YkEGUz9hO5HMupJBldk08cLtRnRWL5lcGmDjdPQc1wU2MoXsSKYzCoIL6D7vEvzwpwkB9bh9GnKVWC3Eq6jHgTiXo14BHE0LrUDJzo9qwHBhc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=2V48mEFq; arc=none smtp.client-ip=209.85.216.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="2V48mEFq" Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-34ab8aafd24so2365363a91.0 for ; Fri, 23 Jan 2026 09:55:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1769190912; x=1769795712; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=NPeVUuvA13SnNgf5n/5K2Vk+ZBZy/3r1jk8iaT+1VRQ=; b=2V48mEFqd8LqPsGqiMTb7ZYSHfnZM7Gyuc0J77MtTvBD5R3X5AIb0brd1scnVmCflg RL+X1xrTX/8VxL8hfBI0LRATKG9u7BzqXFp81Bh3GY7OJDK1pjbNiaEObmAcpKjswDKr INQ8zKmBtnxin5fwjzd4ognzQ+Ln1Y+oJXzacvewVyVa2VkK3mFrQzUb4R3dJTNR1uDI DQAUUaFdJqiIE85hD7BYO9kxwH+qqOi6ZRj+8E9lVyccun2Nk18l/zx3bmRDGRVQa65z wTc6Sko6VcmJwlkQlbUr/vKaDBYvzIe7PK8dDJ+mk4yrCDrrrEFc0or/n+tg3UEhtBKY FFdQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1769190912; x=1769795712; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=NPeVUuvA13SnNgf5n/5K2Vk+ZBZy/3r1jk8iaT+1VRQ=; b=STSBqFnmCrufx/Qd0TxO6qZVigJ577m+Ao/PKPC9d0kdkk4HJbc8qpOjFrlPvCZw8r 00ElYU5V6Lo8sUZFQS0gRcMyGJlR+XIGAwRIgqQG80zrYUNzHsF5MqujS+Koydu2XIOu nQYaWBWlSDktIURS+2QBMr3ZP5HeFdWr2rF/0R1GlseRNC0tw0StRL3O+FIZCzMKFFTO 4yybAgVws/jOm57Eg5DKVKO68KdE+6d4Lwn94nCvFhvuIALN8XNk5VBuQnyyoLxq94So fVhnpFureX5U/h7gcXrJ2FCilnEklG/DWJF4OrOvCEDIACYZ9juWQjNHttAu52FJkqwg WxCw== X-Forwarded-Encrypted: i=1; AJvYcCVUitRz7RgcGh1+mNSKPk6jP8yR9EzkZaWyhJRVZptNGXZdU7/TSDnUM8tJ6+9w9WxWiFw=@vger.kernel.org X-Gm-Message-State: AOJu0Yzh+C0HyoOO+BJvNWRkW6XOmLDlO1J9ISs5VbVYk2KC87xX+jMs P/tGr8asqbeKH46chRU48Nmq69c/A0PNMOd568yBtugnznkfgV7OLnx3Iphfk4J90kDL7MuHc3q kLliGtQ== X-Received: from pjbsl12.prod.google.com ([2002:a17:90b:2e0c:b0:34c:3c14:d369]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:55ce:b0:34c:718c:5448 with SMTP id 98e67ed59e1d1-35335276155mr5631730a91.4.1769190912428; Fri, 23 Jan 2026 09:55:12 -0800 (PST) Date: Fri, 23 Jan 2026 09:55:10 -0800 In-Reply-To: <20251120050720.931449-3-zhao1.liu@intel.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251120050720.931449-1-zhao1.liu@intel.com> <20251120050720.931449-3-zhao1.liu@intel.com> Message-ID: Subject: Re: [PATCH 2/4] KVM: x86: Advertise AMX CPUIDs in subleaf 0x1E.0x1 to userspace From: Sean Christopherson To: Zhao Liu Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H . Peter Anvin" , Paolo Bonzini , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Chao Gao , Xudong Hao Content-Type: text/plain; charset="us-ascii" On Thu, Nov 20, 2025, Zhao Liu wrote: > diff --git a/arch/x86/kvm/reverse_cpuid.h b/arch/x86/kvm/reverse_cpuid.h > index 743ab25ba787..99ec9e656655 100644 > --- a/arch/x86/kvm/reverse_cpuid.h > +++ b/arch/x86/kvm/reverse_cpuid.h > @@ -44,6 +44,16 @@ > #define KVM_X86_FEATURE_BHI_CTRL KVM_X86_FEATURE(CPUID_7_2_EDX, 4) > #define X86_FEATURE_MCDT_NO KVM_X86_FEATURE(CPUID_7_2_EDX, 5) > > +/* Intel-defined sub-features, CPUID level 0x0000001E:1 (EAX) */ > +#define X86_FEATURE_AMX_INT8_MIRROR KVM_X86_FEATURE(CPUID_1E_1_EAX, 0) /* Mirror of X86_FEATURE_AMX_INT8 */ > +#define X86_FEATURE_AMX_BF16_MIRROR KVM_X86_FEATURE(CPUID_1E_1_EAX, 1) /* Mirror of X86_FEATURE_AMX_BF16 */ > +#define X86_FEATURE_AMX_COMPLEX_MIRROR KVM_X86_FEATURE(CPUID_1E_1_EAX, 2) /* Mirror of X86_FEATURE_AMX_COMPLEX */ > +#define X86_FEATURE_AMX_FP16_MIRROR KVM_X86_FEATURE(CPUID_1E_1_EAX, 3) /* Mirror of X86_FEATURE_AMX_FP16 */ Unless someone feels *very* strongly about the "mirror" terminology, I'm going to use ALIAS instead of MIRROR when applying, to match KVM's existing terminology for the 8000_0001.EDX => 1.EDX aliases. /* * Intel-defined sub-features, CPUID level 0x0000001E:1 (EAX). Note, several * of the bits are aliases to features of the same name that are enumerated via * various CPUID.0x7 sub-leafs. */ #define X86_FEATURE_AMX_INT8_ALIAS KVM_X86_FEATURE(CPUID_1E_1_EAX, 0) #define X86_FEATURE_AMX_BF16_ALIAS KVM_X86_FEATURE(CPUID_1E_1_EAX, 1) #define X86_FEATURE_AMX_COMPLEX_ALIAS KVM_X86_FEATURE(CPUID_1E_1_EAX, 2) #define X86_FEATURE_AMX_FP16_ALIAS KVM_X86_FEATURE(CPUID_1E_1_EAX, 3)