From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 717841BF7FD; Wed, 21 Aug 2024 15:40:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724254819; cv=none; b=JxI8n2bL5gzWkUBmNjOdnETmQMg1FL280kuyFDtadhrxng04BjeezXRa3dr7C98Iry/X4a7YpsraGy4rZi5kriezfs+krtvCdpgXuI4d+gxnvasG0Ft0B1DJ17C2scjsbVUz97c8uIXv0iKAA/8Oe7jtR7lmTXk8mP8wCcFHE1k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724254819; c=relaxed/simple; bh=Php0S2nmzRcqf9/Yv7HaFIlkeydQxoapQWlvgRtQMAA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=oZwsz8GhHPgesBtm11b2JGQlpiRY3nkRpJ+NfAjoDYLfjsRUWX4k0T3Q/P4bdgd3xXc+F3RcJckIR0P4mekPmKSSMrJE/BEaYTC2Nqv2feBYwzjZHAncV2TQr/PR/IaWyFdhtZEL+JNlBlvt0AHqMiGM5qxLw+hweDQmfunVT2E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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); } -- 2.34.1