From patchwork Tue Oct 1 05:01:00 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xin Li X-Patchwork-Id: 13817470 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 4F4BF1BC091; Tue, 1 Oct 2024 05:02:18 +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=1727758940; cv=none; b=qeA05Kjkq5TEzst1elHostm8t2BDer/TWUIR5KqzXQXDEgsH9o+DoySEnwTUyng++WgmwPlaVh8yKLrYScfVpjpCRPjhlNbidr7V69VpxdY/rfe7JLrj6hsy/WcVo5PWXla+nV83aFZpg5Snq6b1wGvLs9wcOtEBEyfhHp3I4dQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727758940; c=relaxed/simple; bh=cCXS3QGJ3gGL/feyhUz/mholtXE/la9yMJrsJIIa3Z8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BFoTfrXXXUul3Zt3RPvTKyXS/c+vAVgcG+9fFZnSL5WpvHhD8TXqpxAQqHv/7UL1t2DH31k8ZrqhepFX/E87i5lDMaObiOfm1pNpvfbiXB7pFmasQi4pjQ+ItS89wr5NBsghaOsE/y90fP3J21Fl3M3x91D+zJNUoSd8xGFReVk= 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=QITtegD9; 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="QITtegD9" Received: from terminus.zytor.com (terminus.zytor.com [IPv6:2607:7c80:54:3:0:0:0:136]) (authenticated bits=0) by mail.zytor.com (8.18.1/8.17.1) with ESMTPSA id 49151A7g3643828 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Mon, 30 Sep 2024 22:01:32 -0700 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.zytor.com 49151A7g3643828 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2024091601; t=1727758893; bh=UYAkdDGgqqEL7Q7x/r0wK+q8dSQmiECINofEe79ZVk4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QITtegD9RMAjCLagc7MIyxSEcq6XAQBaZEjdFbyKoYl5jNyirtuGTieqtNlwWM8xD DAKv3wccYOa66wR1PHKWBIHjos1AX3coG1V8z8zyGnrwsrbhoGG/L6bDSk7VTxG/kO HEFRhw/PP0uiLMdUtgGhaCUqhkjSbwkhqwZ7ei+o6ko+MtmFSxO7c3JkOXPzC9tc5I SBtQ+De1WSSWx0/FM3K8XFJgBiL34ErT1fZa3fAhqEQWLNMM91g9L/NkZrju1KOxP+ an27O7U/AAj/AH22Y8cFNYGgKrd1Mde2VSZtmUQKuKDDo20gQYWRVlTUo8el76pDoT plDhi9IadUp2Q== From: "Xin Li (Intel)" To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org Cc: seanjc@google.com, 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, xin@zytor.com Subject: [PATCH v3 17/27] KVM: x86: Mark CR4.FRED as not reserved when guest can use FRED Date: Mon, 30 Sep 2024 22:01:00 -0700 Message-ID: <20241001050110.3643764-18-xin@zytor.com> X-Mailer: git-send-email 2.46.2 In-Reply-To: <20241001050110.3643764-1-xin@zytor.com> References: <20241001050110.3643764-1-xin@zytor.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Xin Li The CR4.FRED bit, i.e., CR4[32], is no longer a reserved bit when guest can use FRED, i.e., 1) All of FRED KVM support is in place. 2) Guest enumerates FRED. Otherwise it is still a reserved bit. Signed-off-by: Xin Li Signed-off-by: Xin Li (Intel) Tested-by: Shan Kang --- Changes since v2: * Don't allow CR4.FRED=1 before all of FRED KVM support is in place (Sean Christopherson). --- arch/x86/include/asm/kvm_host.h | 2 +- arch/x86/kvm/vmx/vmx.c | 4 ++++ arch/x86/kvm/x86.h | 2 ++ 3 files changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 3830084b569b..87f9f0b6cf3c 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -136,7 +136,7 @@ | X86_CR4_OSXSAVE | X86_CR4_SMEP | X86_CR4_FSGSBASE \ | X86_CR4_OSXMMEXCPT | X86_CR4_LA57 | X86_CR4_VMXE \ | X86_CR4_SMAP | X86_CR4_PKE | X86_CR4_UMIP \ - | X86_CR4_LAM_SUP)) + | X86_CR4_LAM_SUP | X86_CR4_FRED)) #define CR8_RESERVED_BITS (~(unsigned long)X86_CR8_TPR) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 03f42b218554..bfdd10773136 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -8009,6 +8009,10 @@ void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_LAM); kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_FRED); + /* Don't allow CR4.FRED=1 before all of FRED KVM support is in place. */ + if (!guest_can_use(vcpu, X86_FEATURE_FRED)) + vcpu->arch.cr4_guest_rsvd_bits |= X86_CR4_FRED; + vmx_setup_uret_msrs(vmx); if (cpu_has_secondary_exec_ctrls()) diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 992e73ee2ec5..0ed91512b757 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -561,6 +561,8 @@ enum kvm_msr_access { __reserved_bits |= X86_CR4_PCIDE; \ if (!__cpu_has(__c, X86_FEATURE_LAM)) \ __reserved_bits |= X86_CR4_LAM_SUP; \ + if (!__cpu_has(__c, X86_FEATURE_FRED)) \ + __reserved_bits |= X86_CR4_FRED; \ __reserved_bits; \ })