From patchwork Wed Aug 21 15:38:20 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Price X-Patchwork-Id: 13771853 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 94E60C52D6F for ; Wed, 21 Aug 2024 15:53:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=suaYPjnxsD7FlJl6FLSk7Zx/T+i304Sjv/eq32HjbzY=; b=rnObsDcTYTGHbjB4k3fUDlzUc4 kU/Jgy9TNjrYap4rf9odMrcI0X/R5ug4gpLaxM6xJnusrub13EMhuSNV9meWqr4Mi/9aQspXSjaPc Yrf06dF5kzdAVJec53YGdLZu58TqP1MbkfLO9DvNDohKGD+ayWJ7B1Beiss/nA65NEieP3FVP9OtW L+LE3Ij8Xxl14MuLupVHOCcdKKhX6LuDlI7IFh9SZINdMSwNrJMIW/k13Qh/GzdMmfRxsl4UV3gMq ytKNNj2207/iVqdKRVNxYdrR9i+OQZK+Pv12A5+rwD2PAu3VF/eNC2y/rtOXNcjJSB+jEwdEc+z8V dz1J9CQg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sgned-00000009bxJ-2P7U; Wed, 21 Aug 2024 15:53:47 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sgnRa-00000009XJa-26MB for linux-arm-kernel@lists.infradead.org; Wed, 21 Aug 2024 15:40:19 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 20622DA7; Wed, 21 Aug 2024 08:40:44 -0700 (PDT) Received: from e122027.cambridge.arm.com (e122027.cambridge.arm.com [10.1.37.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5395C3F73B; Wed, 21 Aug 2024 08:40:14 -0700 (PDT) From: Steven Price To: kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Steven Price , Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , Suzuki K Poulose , Zenghui Yu , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Joey Gouly , Alexandru Elisei , Christoffer Dall , Fuad Tabba , linux-coco@lists.linux.dev, Ganapatrao Kulkarni , Gavin Shan , Shanker Donthineni , Alper Gun Subject: [PATCH v4 19/43] KVM: arm64: Handle realm MMIO emulation Date: Wed, 21 Aug 2024 16:38:20 +0100 Message-Id: <20240821153844.60084-20-steven.price@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240821153844.60084-1-steven.price@arm.com> References: <20240821153844.60084-1-steven.price@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240821_084018_625503_055A67DF X-CRM114-Status: GOOD ( 14.66 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org MMIO emulation for a realm cannot be done directly with the VM's registers as they are protected from the host. However, for emulatable data aborts, the RMM uses GPRS[0] to provide the read/written value. We can transfer this from/to the equivalent VCPU's register entry and then depend on the generic MMIO handling code in KVM. For a MMIO read, the value is placed in the shared RecExit structure during kvm_handle_mmio_return() rather than in the VCPU's register entry. Signed-off-by: Steven Price --- v3: Adapt to previous patch changes --- arch/arm64/kvm/mmio.c | 10 +++++++++- arch/arm64/kvm/rme-exit.c | 6 ++++++ 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c index cd6b7b83e2c3..dbd06ca368e8 100644 --- a/arch/arm64/kvm/mmio.c +++ b/arch/arm64/kvm/mmio.c @@ -6,6 +6,7 @@ #include #include +#include #include #include "trace.h" @@ -90,6 +91,9 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu) vcpu->mmio_needed = 0; + if (vcpu_is_rec(vcpu)) + vcpu->arch.rec.run->enter.flags |= RMI_EMULATED_MMIO; + if (!kvm_vcpu_dabt_iswrite(vcpu)) { struct kvm_run *run = vcpu->run; @@ -108,7 +112,11 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu) trace_kvm_mmio(KVM_TRACE_MMIO_READ, len, run->mmio.phys_addr, &data); data = vcpu_data_host_to_guest(vcpu, data, len); - vcpu_set_reg(vcpu, kvm_vcpu_dabt_get_rd(vcpu), data); + + if (vcpu_is_rec(vcpu)) + vcpu->arch.rec.run->enter.gprs[0] = data; + else + vcpu_set_reg(vcpu, kvm_vcpu_dabt_get_rd(vcpu), data); } /* diff --git a/arch/arm64/kvm/rme-exit.c b/arch/arm64/kvm/rme-exit.c index f4e45d475798..03ed147f7926 100644 --- a/arch/arm64/kvm/rme-exit.c +++ b/arch/arm64/kvm/rme-exit.c @@ -25,6 +25,12 @@ static int rec_exit_reason_notimpl(struct kvm_vcpu *vcpu) static int rec_exit_sync_dabt(struct kvm_vcpu *vcpu) { + struct realm_rec *rec = &vcpu->arch.rec; + + if (kvm_vcpu_dabt_iswrite(vcpu) && kvm_vcpu_dabt_isvalid(vcpu)) + vcpu_set_reg(vcpu, kvm_vcpu_dabt_get_rd(vcpu), + rec->run->exit.gprs[0]); + return kvm_handle_guest_abort(vcpu); }