From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (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 6E58D63CB for ; Sat, 7 Mar 2026 02:15:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772849732; cv=none; b=ZevVbS1k6y2xZ7i4Kf4u65k9qO0ozp55skdMQ3ld/3ERTObkperoRJb+7EdayhKPsF+jU6Zb3kCB1ltdCZtI8WK1AZJjVt3hp1WqnwBh1qLK/9U2shK2EoQAZBnPh6y5tyh+UAhIwTHlVSv5m7e022QfuDtwDEG+TmAWegIKgtE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772849732; c=relaxed/simple; bh=uXG19vgyqc0vRsqQoQGiphZhjsSOgse8qk3/8sYdk4Y=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=CsVeZj5IPqrRhywhTXLOGTmdJpTRd3JTKiwXCDCnupacBvHG+IylqLcfaulwFFi5wqWxtMkX3AMkwPRTGGHuKAMBmjpS7zcZUrph3y8YZKn94tGW99EJgv4w4vmatYZoEQZjeeCoNXbg4krD7RoH+ErkfdXmgKw7ZlZetVF/V9I= 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=r80h1+Z9; arc=none smtp.client-ip=209.85.214.201 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="r80h1+Z9" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-2ae5031c6b1so56004625ad.0 for ; Fri, 06 Mar 2026 18:15:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1772849731; x=1773454531; 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=hpHs4vUYCe8FUMxp12xFtu/nT5nIlsGpqATm6Mj9k5U=; b=r80h1+Z9+s2t65aoHNhpqg75Ql64gn5SNeuHov736rWVkSUIGBS8X8Gts1mbcxknsn tSrMJ7Hy+opny4bwleSM4a555ir1HR/CMFl47eZGFOsCFieTHlp2jAXQibikhpvfcyv6 1a2uzpqOA8rwuSv3CDyoKkdmkqMrN5CXv4GoDU5fIw6GFdgq+7I4QrUV8A7npF293Vbh TtZn44HDdDh8sku/s29GZSHVxgpkjRpIaVYMQ7myAAe/OF4gJNCGbE8xCKYL0ljNbLjz WQNKjMLrjX0CwGgnSyeNkAEyZFeQV1Rq2E1IGtyLzfe7erq/4Id+utrnHbd1iyeYk+0I 895A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1772849731; x=1773454531; 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=hpHs4vUYCe8FUMxp12xFtu/nT5nIlsGpqATm6Mj9k5U=; b=P9vDyHYdchRegIRNPPRoQ1eDiwWKHxlK297tFz4K7lOGyCFkh7r0ygMWHpI/Yl+VKU txh63m2y55lzm/OCGHGhxOCJhfSS0fjlHTOH7Ovx1892dVFb2850bUMhJ6XdzOBsThPk 6gD5WyqFWmcuoROcR7gNb38EN03Uuw6bEpjREK1owPI+/gK9IHXnQ0j4z7QZFhWuWoFo 35IrbhMr05KwnRL0VnEwcufmW+9QzuuZsWGhrfkG+8mmmklnUIvBr1+B/2qbw+fRXObH q5M4Yr2g9ePlvKHKCYyNypuME2MIg4xJIjl39p7FOXIM2iliHFXuqyTlQyf+bzOqE5cR CGiw== X-Forwarded-Encrypted: i=1; AJvYcCU7HTJV+1BXLj6ttzNy382KcBzPBJ7A85z26cPwelPYhkJL6yboUDbNVm2cMV93Jor11rT4DjWSaA8=@vger.kernel.org X-Gm-Message-State: AOJu0YzcYQP6U5tl3LayAyYXx/gpQrCLimu0WbfEaFLmzCt7tag9KG1Z J1UKvYPvYSFLACeISwkGrpNC58sNUwBxluzw0KbFho8Of4/f0OHXRBjotL1EdrHIZpqLp/n5hTq P1OHTkQ== X-Received: from plbmj3.prod.google.com ([2002:a17:903:2b83:b0:2ae:3e55:f044]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:ef10:b0:2aa:d671:e613 with SMTP id d9443c01a7336-2ae8245165cmr48752275ad.38.1772849730693; Fri, 06 Mar 2026 18:15:30 -0800 (PST) Date: Fri, 6 Mar 2026 18:15:29 -0800 In-Reply-To: <20250829153149.2871901-17-xin@zytor.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250829153149.2871901-1-xin@zytor.com> <20250829153149.2871901-17-xin@zytor.com> Message-ID: Subject: Re: [PATCH v7 16/21] KVM: x86: Advertise support for FRED From: Sean Christopherson To: "Xin Li (Intel)" Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, pbonzini@redhat.com, corbet@lwn.net, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, peterz@infradead.org, andrew.cooper3@citrix.com, chao.gao@intel.com, hch@infradead.org Content-Type: text/plain; charset="us-ascii" On Fri, Aug 29, 2025, Xin Li (Intel) wrote: > From: Xin Li > > Advertise support for FRED to userspace after changes required to enable > FRED in a KVM guest are in place. Mostly a note to myself, if VMX and SVM land separately, we need to do the same thing we did for CET and explicitly clear FRED in svm_set_cpu_caps(). But ideally this would just be the last patch after both VMX and SVM support are in place. > Signed-off-by: Xin Li > Signed-off-by: Xin Li (Intel) > Tested-by: Shan Kang > Tested-by: Xuelian Guo > --- > > Change in v5: > * Don't advertise FRED/LKGS together, LKGS can be advertised as an > independent feature (Sean). > * Add TB from Xuelian Guo. > --- > arch/x86/kvm/cpuid.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c > index ee05b876c656..1f15aad02c68 100644 > --- a/arch/x86/kvm/cpuid.c > +++ b/arch/x86/kvm/cpuid.c > @@ -994,6 +994,7 @@ void kvm_set_cpu_caps(void) > F(FSRS), > F(FSRC), > F(WRMSRNS), > + X86_64_F(FRED), > X86_64_F(LKGS), > F(AMX_FP16), > F(AVX_IFMA), > -- > 2.51.0 >