From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (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 21F5F223DDD for ; Tue, 8 Jul 2025 14:37:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751985434; cv=none; b=M9VK0JpXXALp7Q2KFgyrB3iIOVdYA2JKlWB1imaIgDow61Yzkvrpk4JH3ijo6++ojh+Znn1ggc0QQzdIWKcGshSqZbcaRQ8Xft+1R/YPx5BVAFwhxCpNOj3buVoXQ5fo+kt+aSsWbsHWWWnrpWXbyypcbk7Xl3a4LQN0pPKnpNo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751985434; c=relaxed/simple; bh=kLDmLW0i8VTZ3UXPuyNLfg15+1/PDr9DpXKxRYPwAGc=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=AhVI+Yk6l2qZUbKUHT2AwqbM/RawAbCv9I9pFMDw85Bc2fduda5E2I5SwQIDvDxIm8axdlYBAgRZM6173SCZOvDFx5hB2Xc1u4ylSuD4ozKJ7x0MSfn93NsRIY7jNYQw65hBwN7rF7cVuU1FkcEdvftzT08BhY/z9GuZ9JtGZBQ= 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=Arum+Yy8; arc=none smtp.client-ip=209.85.214.202 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="Arum+Yy8" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-23689228a7fso60473365ad.1 for ; Tue, 08 Jul 2025 07:37:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1751985432; x=1752590232; 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=CSr9DnGC0U+Ld1MVeE/odpdQ4lfNnPFU9ZNv9t6sQpk=; b=Arum+Yy87asJgChhwKW0mtnB8f55Ioojnd+ay8qlCFlNFyAmoxtQcJNPb4rBaG6bI1 QaZJoZkimefeMpO7lWMy0xZvt3ZNRpo/YZzpe35aebqdebCYvaJw1/BoSZAyEVq7fE7A Pw20KaGOryIX1N5kNiLI7AZfyBNaOFLoUliom8Jmowsdmz1w/M5FSNGoej2Sx3H68pgJ MCSzO5Dp6P75OgseXXfwPNQU76xS2MoJBhfioSnSAWDdSp46OJ7G6yDPBj3aUuFKtycc UBZpHtZG8oZOMptdXBjYBLpfGrIdHPwRUhS71sSq1NAXE60y+9GkVEQ4xOaSqnsxJ5gM z4ZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1751985432; x=1752590232; 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=CSr9DnGC0U+Ld1MVeE/odpdQ4lfNnPFU9ZNv9t6sQpk=; b=nLtjLu3K//zoWkhHMa8XkmL6HggF+TJDJL920wVBOz7sJnQ3GqHUhUOpEz1uWlo8g8 ia/sDWMIVDQdKukTEoJ61ognO8HudN/7G4FQc4mk9/jLvxQ3yIA63GWp2nPIze+6gvcP AbTjg0XEW7l8S/t+tFhfFrel9++4DBlMJ0//8qJqs0vKm/0iy8zzYcJXOEFsErO2aHOv YrEDH1PyxYFPVeMLRDDe2DUq0+lobIbuEahrvbkivRuQiPmpB3wTRCDxMj41BxZ+eOO0 eRNM6WsZ3v3o4VJgWCYpz9CRP6Cwh+8k9zrMck8byKmxkEOhYbkUkERV57kRe3NjZQWB xxug== X-Forwarded-Encrypted: i=1; AJvYcCXFG6os1uktyWaoXGm6j6RJ99r7qiU4UjRsHC5Jw9E+8uuxRbpH+81PLjdqL1KvLtisO8o=@vger.kernel.org X-Gm-Message-State: AOJu0YwptNJ4ry7S7gXVGRXit3GDpr5csIZ+KNOVmfFEFmb4vGWbta0K np+l9nxr45awGrdS4XirKiGEe0R5ryHthWIMMbgjjUgtPx4D84blttdN8cVrvAdCgjDFh2kvl1B Zu3W5HQ== X-Google-Smtp-Source: AGHT+IHL5BLmNe8HQ8sUJcUtqOgA4+QupQWiYZFvsZZxYR10RLA26WOSa/tnxreZzc7IJ6XfjLE8If7qRsA= X-Received: from plsl15.prod.google.com ([2002:a17:903:244f:b0:234:c2e4:1df6]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:dac8:b0:236:363e:55d with SMTP id d9443c01a7336-23dd1d2eb19mr45240215ad.28.1751985432367; Tue, 08 Jul 2025 07:37:12 -0700 (PDT) Date: Tue, 8 Jul 2025 07:37:10 -0700 In-Reply-To: <20250707101029.927906-3-nikunj@amd.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250707101029.927906-1-nikunj@amd.com> <20250707101029.927906-3-nikunj@amd.com> Message-ID: Subject: Re: [PATCH v8 2/2] KVM: SVM: Enable Secure TSC for SNP guests From: Sean Christopherson To: Nikunj A Dadhania Cc: pbonzini@redhat.com, kvm@vger.kernel.org, thomas.lendacky@amd.com, santosh.shukla@amd.com, bp@alien8.de, isaku.yamahata@intel.com, vaishali.thakkar@suse.com, kai.huang@intel.com Content-Type: text/plain; charset="us-ascii" On Mon, Jul 07, 2025, Nikunj A Dadhania wrote: > Introduce the read-only MSR GUEST_TSC_FREQ (0xc0010134) that returns > guest's effective frequency in MHZ when Secure TSC is enabled for SNP > guests. Disable interception of this MSR when Secure TSC is enabled. Note > that GUEST_TSC_FREQ MSR is accessible only to the guest and not from the > hypervisor context. ... > @@ -4487,6 +4512,9 @@ static void sev_es_init_vmcb(struct vcpu_svm *svm) > > /* Can't intercept XSETBV, HV can't modify XCR0 directly */ > svm_clr_intercept(svm, INTERCEPT_XSETBV); > + > + if (snp_secure_tsc_enabled(svm->vcpu.kvm)) > + svm_disable_intercept_for_msr(&svm->vcpu, MSR_AMD64_GUEST_TSC_FREQ, MSR_TYPE_RW); KVM shouldn't be disabling write interception for a read-only MSR. And this code belongs in sev_es_recalc_msr_intercepts().