From mboxrd@z Thu Jan 1 00:00:00 1970 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 D75A2C4332F for ; Mon, 7 Nov 2022 14:57:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232745AbiKGO5W (ORCPT ); Mon, 7 Nov 2022 09:57:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232714AbiKGO4g (ORCPT ); Mon, 7 Nov 2022 09:56:36 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 97ABBFD32 for ; Mon, 7 Nov 2022 06:54:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1667832884; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=HxC4ET12VN55YVyqetOo6RD2ywSPtMRXUSJhnwR7Q90=; b=RvexNNAWvPHr6982FmBe3WP9N8djNnKF7qcMiKNf4jefTvmicOLv4pd0Vt7FNZn7P9rTWp pIe8P8c7fdwlMKRHw1Lx+NCTLonyOhqIzTN+3QkhG+vfllBSWrfUBQ/As9zj/q1JFxK/nu fEEFj0ZZBhp0QjlH0q1AbsRqNE/M93c= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-390-gCx0CZFfMB68ZukcM2s1_g-1; Mon, 07 Nov 2022 09:54:39 -0500 X-MC-Unique: gCx0CZFfMB68ZukcM2s1_g-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 27F22101A52A; Mon, 7 Nov 2022 14:54:39 +0000 (UTC) Received: from virtlab701.virt.lab.eng.bos.redhat.com (virtlab701.virt.lab.eng.bos.redhat.com [10.19.152.228]) by smtp.corp.redhat.com (Postfix) with ESMTP id E29ED2027061; Mon, 7 Nov 2022 14:54:38 +0000 (UTC) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: nathan@kernel.org, thomas.lendacky@amd.com, andrew.cooper3@citrix.com, peterz@infradead.org, jmattson@google.com, seanjc@google.com, stable@vger.kernel.org Subject: [PATCH 6/8] KVM: SVM: restore host save area from assembly Date: Mon, 7 Nov 2022 09:54:34 -0500 Message-Id: <20221107145436.276079-7-pbonzini@redhat.com> In-Reply-To: <20221107145436.276079-1-pbonzini@redhat.com> References: <20221107145436.276079-1-pbonzini@redhat.com> MIME-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is needed so that FILL_RETURN_BUFFER has access to the percpu area via the GS segment base. Cc: stable@vger.kernel.org Fixes: f14eec0a3203 ("KVM: SVM: move more vmentry code to assembly") Reported-by: Nathan Chancellor Analyzed-by: Andrew Cooper Signed-off-by: Paolo Bonzini --- arch/x86/kvm/svm/svm.c | 3 +-- arch/x86/kvm/svm/svm.h | 2 +- arch/x86/kvm/svm/svm_ops.h | 5 ----- arch/x86/kvm/svm/vmenter.S | 13 +++++++++++++ 4 files changed, 15 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 550a364be8d3..381c7dcffe25 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -3923,8 +3923,7 @@ static noinstr void svm_vcpu_enter_exit(struct kvm_vcpu *vcpu) } else { struct svm_cpu_data *sd = per_cpu(svm_data, vcpu->cpu); - __svm_vcpu_run(svm); - vmload(__sme_page_pa(sd->save_area)); + __svm_vcpu_run(svm, __sme_page_pa(sd->save_area)); } guest_state_exit_irqoff(); diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index c5b8ec370108..99410651f2a5 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -484,6 +484,6 @@ void sev_es_unmap_ghcb(struct vcpu_svm *svm); /* vmenter.S */ void __svm_sev_es_vcpu_run(struct vcpu_svm *svm); -void __svm_vcpu_run(struct vcpu_svm *svm); +void __svm_vcpu_run(struct vcpu_svm *svm, unsigned long hsave_pa); #endif diff --git a/arch/x86/kvm/svm/svm_ops.h b/arch/x86/kvm/svm/svm_ops.h index 9430d6437c9f..36c8af87a707 100644 --- a/arch/x86/kvm/svm/svm_ops.h +++ b/arch/x86/kvm/svm/svm_ops.h @@ -61,9 +61,4 @@ static __always_inline void vmsave(unsigned long pa) svm_asm1(vmsave, "a" (pa), "memory"); } -static __always_inline void vmload(unsigned long pa) -{ - svm_asm1(vmload, "a" (pa), "memory"); -} - #endif /* __KVM_X86_SVM_OPS_H */ diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S index 9738ce41fac9..45a4bd002494 100644 --- a/arch/x86/kvm/svm/vmenter.S +++ b/arch/x86/kvm/svm/vmenter.S @@ -35,6 +35,7 @@ /** * __svm_vcpu_run - Run a vCPU via a transition to SVM guest mode * @svm: struct vcpu_svm * + * @hsave_pa: unsigned long */ SYM_FUNC_START(__svm_vcpu_run) push %_ASM_BP @@ -49,6 +50,9 @@ SYM_FUNC_START(__svm_vcpu_run) #endif push %_ASM_BX + /* @hsave_pa is needed last after vmexit, save it first. */ + push %_ASM_ARG2 + /* Save @svm. */ push %_ASM_ARG1 @@ -124,6 +128,11 @@ SYM_FUNC_START(__svm_vcpu_run) 5: vmsave %_ASM_AX 6: + /* Pop @hsave_pa and restore GSBASE, allowing access to percpu data. */ + pop %_ASM_AX +7: vmload %_ASM_AX +8: + #ifdef CONFIG_RETPOLINE /* IMPORTANT: Stuff the RSB immediately after VM-Exit, before RET! */ FILL_RETURN_BUFFER %_ASM_AX, RSB_CLEAR_LOOPS, X86_FEATURE_RETPOLINE @@ -187,10 +196,14 @@ SYM_FUNC_START(__svm_vcpu_run) 50: cmpb $0, kvm_rebooting jne 6b ud2 +70: cmpb $0, kvm_rebooting + jne 8b + ud2 _ASM_EXTABLE(1b, 10b) _ASM_EXTABLE(3b, 30b) _ASM_EXTABLE(5b, 50b) + _ASM_EXTABLE(7b, 70b) SYM_FUNC_END(__svm_vcpu_run) -- 2.31.1