From nobody Sat Oct 4 06:37:13 2025 Received: from mail-pg1-f202.google.com (mail-pg1-f202.google.com [209.85.215.202]) (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 A4DD82D24BD for ; Tue, 19 Aug 2025 23:48:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755647332; cv=none; b=T797yD3RejaRNxROEzdXss/rUf7CJZ4JIH2jOSU6wm2YAjmDvDz0Rs28lkvb/VDCYJft+dKQl2VwYlUGok6og09cBlO1XZpneNxzT5BhO8SaTDh08/pFwmmwSqdLv5OGSIbOk16bzd/qIo0Dhwy6wwoGoVJZWN78Ly6uCpTXEtU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755647332; c=relaxed/simple; bh=9fPRpXTZO2yXI/PNnKA2idpDZL7e+fha1bGtzAVD6Bg=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=Scs6mGCudCOXpMGHCrzO+7onAdozzlkTvQW80vTpCSiQOE9ZaCxcjEsLG199N59GFtTatH+WJTYaTF0W8mS/GwMYaxPJzDCYLrvxIL5zqXUAOf0Lb6amO6BjSrxNl0SRKu6u0bMkIjJ0xpzVV+DZHaL/AWEoXSOw6aBrp7b0lRw= 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=WskXFAIp; arc=none smtp.client-ip=209.85.215.202 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="WskXFAIp" Received: by mail-pg1-f202.google.com with SMTP id 41be03b00d2f7-b4731a95beeso8003132a12.0 for ; Tue, 19 Aug 2025 16:48:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1755647330; x=1756252130; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=OqVMINvdACt4jkEJXLjx81Yg3Bj21o74SrPjsSKAbyI=; b=WskXFAIpcZIidH8t1+uKWjlSKaeFvKr+veR5oVSQTzg+/iPLlPU39sxfBsGIM+JeId ezFpwwHxfXfMOdcNyh0MO/2q7U+IHCz1gEvLUrjllHDkMjUsCKB6cEKZ0b6GWtuOpv8b vkKgl0nizb27JRrq8yQC92z81Aw9yjpQKa5UDx8QySfSixyAV+qIovgW3t/lFDEj4LUD beuxKd0lVhpjdfAa2spsFIT2n3NYoNsEetg9SwaRM8OZ+TsEVy+XHv+SA+C1Ki38Pmkn m7nh/lbWqybEUf4CksMZhqhDjHJ1DfQbDMt9Lszgrl8b/f4KZfLhfVPTF/UbI4OQzPnb MDAA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1755647330; x=1756252130; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=OqVMINvdACt4jkEJXLjx81Yg3Bj21o74SrPjsSKAbyI=; b=qMjXbFa9wRk/UlxDX7CobgHOyA02K97S6rl2Pz7iZ8J6Po1b1z/Ft2+MhmLS2sj0p0 oKb3/IZDxNpMiGkoAgdyGlqliTqy74XHenmArqpLlTpeisWhdetVFp0ZDhPB+7aKE/Kq rk5zIyrSjScrBkmsDT+rjiThnsWHrt42tOtV7huE2dDlWOjEoYExtpzcyXQb/rJ0d33g rsUUA3AFD1yBYq43l76nqnUwN27p9HWBOyq5uGhBWrRgrjWv9NWbC2T2Ace/hy+xSVsu A/pf1g3nWdLgrCdUDNwQJwgINrvIY0KPpaR7kx53kJYuikxw+Lqz99aNIL3x6INIqF/7 Z+2w== X-Forwarded-Encrypted: i=1; AJvYcCWzKS1SinX3eDYIOd4YN4G8hTY+MtZI26uAruMZRKKb5Kb+VnygVr+kpORHOGGlWrnv8EresQdiQDFLUQ4=@vger.kernel.org X-Gm-Message-State: AOJu0YxuE4jgaDToJuKaKih6YjFRT+zJXuPR1Mdmg1Bn5BVuB96DnfXW O7ECjTcevW4wBRutA8Iwua82igKlXUqoGXCuya3ag6/WEBcYOsYJpXmSXHhzwCBn6I6iX6BzrVQ IPzhJbQ== X-Google-Smtp-Source: AGHT+IGQLMLAQAF+dGlRQvB0Wi/p9jHlXdkYZZaSC9+PUwdFXqoFYw8S9ETM/e2VYLS2EJ9MurtjnbpHAaA= X-Received: from pgou3.prod.google.com ([2002:a63:b543:0:b0:b2f:1e09:528b]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a20:748a:b0:240:eb5:77c6 with SMTP id adf61e73a8af0-2431b9036d5mr1616895637.26.1755647330047; Tue, 19 Aug 2025 16:48:50 -0700 (PDT) Reply-To: Sean Christopherson Date: Tue, 19 Aug 2025 16:48:31 -0700 In-Reply-To: <20250819234833.3080255-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250819234833.3080255-1-seanjc@google.com> X-Mailer: git-send-email 2.51.0.rc1.167.g924127e9c0-goog Message-ID: <20250819234833.3080255-7-seanjc@google.com> Subject: [PATCH v11 6/8] KVM: SEV: Set RESET GHCB MSR value during sev_es_init_vmcb() From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Thomas Lendacky , Michael Roth , Nikunj A Dadhania , Borislav Petkov , Vaishali Thakkar , Ketan Chaturvedi , Kai Huang Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Set the RESET value for the GHCB "MSR" during sev_es_init_vmcb() instead of sev_es_vcpu_reset() to allow for dropping sev_es_vcpu_reset() entirely. Note, the call to sev_init_vmcb() from sev_migrate_from() also kinda sorta emulates a RESET, but sev_migrate_from() immediate overwrites ghcb_gpa with the source's current value, so whether or not stuffing the GHCB version is correct/desirable is moot. No functional change intended. Signed-off-by: Sean Christopherson Reviewed-by: Nikunj A Dadhania --- arch/x86/kvm/svm/sev.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index c5726b091680..ee7a05843548 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -4480,7 +4480,7 @@ void sev_vcpu_after_set_cpuid(struct vcpu_svm *svm) vcpu->arch.reserved_gpa_bits &=3D ~(1UL << (best->ebx & 0x3f)); } =20 -static void sev_es_init_vmcb(struct vcpu_svm *svm) +static void sev_es_init_vmcb(struct vcpu_svm *svm, bool init_event) { struct kvm_sev_info *sev =3D to_kvm_sev_info(svm->vcpu.kvm); struct vmcb *vmcb =3D svm->vmcb01.ptr; @@ -4541,6 +4541,15 @@ static void sev_es_init_vmcb(struct vcpu_svm *svm) =20 /* Can't intercept XSETBV, HV can't modify XCR0 directly */ svm_clr_intercept(svm, INTERCEPT_XSETBV); + + /* + * Set the GHCB MSR value as per the GHCB specification when emulating + * vCPU RESET for an SEV-ES guest. + */ + if (!init_event) + set_ghcb_msr(svm, GHCB_MSR_SEV_INFO((__u64)sev->ghcb_version, + GHCB_VERSION_MIN, + sev_enc_bit)); } =20 void sev_init_vmcb(struct vcpu_svm *svm, bool init_event) @@ -4560,7 +4569,7 @@ void sev_init_vmcb(struct vcpu_svm *svm, bool init_ev= ent) sev_snp_init_protected_guest_state(vcpu); =20 if (sev_es_guest(vcpu->kvm)) - sev_es_init_vmcb(svm); + sev_es_init_vmcb(svm, init_event); } =20 int sev_vcpu_create(struct kvm_vcpu *vcpu) @@ -4585,17 +4594,6 @@ int sev_vcpu_create(struct kvm_vcpu *vcpu) =20 void sev_es_vcpu_reset(struct vcpu_svm *svm) { - struct kvm_vcpu *vcpu =3D &svm->vcpu; - struct kvm_sev_info *sev =3D to_kvm_sev_info(vcpu->kvm); - - /* - * Set the GHCB MSR value as per the GHCB specification when emulating - * vCPU RESET for an SEV-ES guest. - */ - set_ghcb_msr(svm, GHCB_MSR_SEV_INFO((__u64)sev->ghcb_version, - GHCB_VERSION_MIN, - sev_enc_bit)); - mutex_init(&svm->sev_es.snp_vmsa_mutex); } =20 --=20 2.51.0.rc1.167.g924127e9c0-goog