From nobody Mon Sep 15 11:36:05 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5E45CC67871 for ; Thu, 12 Jan 2023 16:40:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232355AbjALQjl (ORCPT ); Thu, 12 Jan 2023 11:39:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42034 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236181AbjALQhW (ORCPT ); Thu, 12 Jan 2023 11:37:22 -0500 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 66B0711C01; Thu, 12 Jan 2023 08:33:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1673541223; x=1705077223; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=DPQNPByrY2lPsww3gl59qroz4kG/Av+q17xVYdcZNoc=; b=m9C5Kj970z5q58smVX742UfPbZ0/1/CL8U460TQaT3PLtVlsvTn7l08N /G3SehRRXjwW69cWRYaBS5yuPPzpNlPNpqNN1qwelpOwpUeNVHjeeY+Y7 PWoeWSfK8t29qKOHVdM6h/BSGlgUjc2avXIFO3z90dnpkmYT+Tx54N6iJ 5R9Y55erDhY8Sqowg0KCA2i+Bz3OAp2mqgF8Ec7wbLneCO/kTZBdc+A/s eXdr/YXAYqXM1L8ovj64zvv4UnaBLQ7mgnLfCyjSfEveYZwfOk6C3Xi+7 FRFBRW4qtZeuycUEHS1qfZPhhsJj7yPt70uuVxWVYiW7dGLYZknw69Lur w==; X-IronPort-AV: E=McAfee;i="6500,9779,10588"; a="386089695" X-IronPort-AV: E=Sophos;i="5.97,211,1669104000"; d="scan'208";a="386089695" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Jan 2023 08:33:35 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10588"; a="726372536" X-IronPort-AV: E=Sophos;i="5.97,211,1669104000"; d="scan'208";a="726372536" Received: from ls.sc.intel.com (HELO localhost) ([143.183.96.54]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Jan 2023 08:33:35 -0800 From: isaku.yamahata@intel.com To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, Paolo Bonzini , erdemaktas@google.com, Sean Christopherson , Sagi Shahar , David Matlack Subject: [PATCH v11 087/113] KVM: TDX: handle ept violation/misconfig exit Date: Thu, 12 Jan 2023 08:32:35 -0800 Message-Id: <83e6c6ff4cc14860678e6f1456a631d887a96526.1673539699.git.isaku.yamahata@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Isaku Yamahata On EPT violation, call a common function, __vmx_handle_ept_violation() to trigger x86 MMU code. On EPT misconfiguration, exit to ring 3 with KVM_EXIT_UNKNOWN. because EPT misconfiguration can't happen as MMIO is trigged by TDG.VP.VMCALL. No point to set a misconfiguration value for the fast path. Signed-off-by: Isaku Yamahata --- arch/x86/kvm/vmx/tdx.c | 46 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 83df5673d5f2..2bea7c96536b 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -1075,6 +1075,48 @@ void tdx_deliver_interrupt(struct kvm_lapic *apic, i= nt delivery_mode, __vmx_deliver_posted_interrupt(vcpu, &tdx->pi_desc, vector); } =20 +static int tdx_handle_ept_violation(struct kvm_vcpu *vcpu) +{ + unsigned long exit_qual; + + if (kvm_is_private_gpa(vcpu->kvm, tdexit_gpa(vcpu))) { + /* + * Always treat SEPT violations as write faults. Ignore the + * EXIT_QUALIFICATION reported by TDX-SEAM for SEPT violations. + * TD private pages are always RWX in the SEPT tables, + * i.e. they're always mapped writable. Just as importantly, + * treating SEPT violations as write faults is necessary to + * avoid COW allocations, which will cause TDAUGPAGE failures + * due to aliasing a single HPA to multiple GPAs. + */ +#define TDX_SEPT_VIOLATION_EXIT_QUAL EPT_VIOLATION_ACC_WRITE + exit_qual =3D TDX_SEPT_VIOLATION_EXIT_QUAL; + } else { + exit_qual =3D tdexit_exit_qual(vcpu); + if (exit_qual & EPT_VIOLATION_ACC_INSTR) { + pr_warn("kvm: TDX instr fetch to shared GPA =3D 0x%lx @ RIP =3D 0x%lx\n= ", + tdexit_gpa(vcpu), kvm_rip_read(vcpu)); + vcpu->run->exit_reason =3D KVM_EXIT_EXCEPTION; + vcpu->run->ex.exception =3D PF_VECTOR; + vcpu->run->ex.error_code =3D exit_qual; + return 0; + } + } + + trace_kvm_page_fault(vcpu, tdexit_gpa(vcpu), exit_qual); + return __vmx_handle_ept_violation(vcpu, tdexit_gpa(vcpu), exit_qual); +} + +static int tdx_handle_ept_misconfig(struct kvm_vcpu *vcpu) +{ + WARN_ON_ONCE(1); + + vcpu->run->exit_reason =3D KVM_EXIT_UNKNOWN; + vcpu->run->hw.hardware_exit_reason =3D EXIT_REASON_EPT_MISCONFIG; + + return 0; +} + int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath) { union tdx_exit_reason exit_reason =3D to_tdx(vcpu)->exit_reason; @@ -1119,6 +1161,10 @@ int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_= t fastpath) WARN_ON_ONCE(fastpath !=3D EXIT_FASTPATH_NONE); =20 switch (exit_reason.basic) { + case EXIT_REASON_EPT_VIOLATION: + return tdx_handle_ept_violation(vcpu); + case EXIT_REASON_EPT_MISCONFIG: + return tdx_handle_ept_misconfig(vcpu); case EXIT_REASON_OTHER_SMI: /* * If reach here, it's not a Machine Check System Management --=20 2.25.1