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 981D928F0; Fri, 27 Jan 2023 11:41:00 +0000 (UTC) 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 2D1C71764; Fri, 27 Jan 2023 03:41:42 -0800 (PST) Received: from ewhatever.cambridge.arm.com (ewhatever.cambridge.arm.com [10.1.197.1]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 9B35E3F64C; Fri, 27 Jan 2023 03:40:57 -0800 (PST) From: Suzuki K Poulose To: kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: suzuki.poulose@arm.com, Alexandru Elisei , Andrew Jones , Christoffer Dall , Fuad Tabba , Jean-Philippe Brucker , Joey Gouly , Marc Zyngier , Mark Rutland , Oliver Upton , Paolo Bonzini , Quentin Perret , Steven Price , Thomas Huth , Will Deacon , Zenghui Yu , linux-coco@lists.linux.dev, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [RFC kvmtool 25/31] arm64: realm: Double the IPA space Date: Fri, 27 Jan 2023 11:39:26 +0000 Message-Id: <20230127113932.166089-26-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230127113932.166089-1-suzuki.poulose@arm.com> References: <20230127112248.136810-1-suzuki.poulose@arm.com> <20230127113932.166089-1-suzuki.poulose@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 The Realm's IPA space is divided into 2 halves. Protected (lower half) and Unprotected (upper half). KVM implements aliasing of the IPA, where the unprotected IPA is alias of the corresponding protected ipa. Thus we must double the IPA space required for a given VM. Signed-off-by: Suzuki K Poulose --- arm/aarch64/kvm.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arm/aarch64/kvm.c b/arm/aarch64/kvm.c index fca1410b..344c568b 100644 --- a/arm/aarch64/kvm.c +++ b/arm/aarch64/kvm.c @@ -189,6 +189,9 @@ int kvm__get_vm_type(struct kvm *kvm) /* Otherwise, compute the minimal required IPA size */ max_ipa = kvm->cfg.ram_addr + kvm->cfg.ram_size - 1; ipa_bits = max(32, fls_long(max_ipa)); + /* Realm needs double the IPA space */ + if (kvm->cfg.arch.is_realm) + ipa_bits++; pr_debug("max_ipa %lx ipa_bits %d max_ipa_bits %d", max_ipa, ipa_bits, max_ipa_bits); -- 2.34.1