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 X-Spam-Level: X-Spam-Status: No, score=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3AA60C4338F for ; Sun, 22 Aug 2021 15:25:44 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 9C27061262 for ; Sun, 22 Aug 2021 15:25:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 9C27061262 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 3EBE74B1F7; Sun, 22 Aug 2021 11:25:43 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Fa5zzb8aPQOf; Sun, 22 Aug 2021 11:25:38 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id D760D4B1F9; Sun, 22 Aug 2021 11:25:38 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 793CB4B1F7 for ; Sun, 22 Aug 2021 11:25:37 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Ihq-h+sd2NUV for ; Sun, 22 Aug 2021 11:25:36 -0400 (EDT) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 7FF584B1B6 for ; Sun, 22 Aug 2021 11:25:36 -0400 (EDT) Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B399561261; Sun, 22 Aug 2021 15:25:35 +0000 (UTC) Received: from sofa.misterjones.org ([185.219.108.64] helo=hot-poop.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1mHpLq-006VTo-3A; Sun, 22 Aug 2021 16:25:34 +0100 From: Marc Zyngier To: kvmarm@lists.cs.columbia.edu Subject: [PATCH v2 3/3] kvmtool: arm64: Configure VM with the minimal required IPA space Date: Sun, 22 Aug 2021 16:25:26 +0100 Message-Id: <20210822152526.1291918-4-maz@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210822152526.1291918-1-maz@kernel.org> References: <20210822152526.1291918-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.cs.columbia.edu, andre.przywara@arm.com, alexandru.elisei@arm.com, will@kernel.org, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Cc: Andre Przywara , kernel-team@android.com, Will Deacon X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu There is some value in keeping the IPA space small, as it reduces the size of the stage-2 page tables. Let's compute the required space at VM creation time, and inform the kernel of our requirements. Signed-off-by: Marc Zyngier --- arm/aarch64/kvm.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/arm/aarch64/kvm.c b/arm/aarch64/kvm.c index d03a27f2..4e66a22e 100644 --- a/arm/aarch64/kvm.c +++ b/arm/aarch64/kvm.c @@ -3,6 +3,7 @@ #include #include +#include /* * Return the TEXT_OFFSET value that the guest kernel expects. Note @@ -59,5 +60,22 @@ int kvm__arch_get_ipa_limit(struct kvm *kvm) int kvm__get_vm_type(struct kvm *kvm) { - return KVM_VM_TYPE_ARM_IPA_SIZE(kvm__arch_get_ipa_limit(kvm)); + unsigned int ipa_bits, max_ipa_bits; + unsigned long max_ipa; + + /* If we're running on an old kernel, use 0 as the VM type */ + max_ipa_bits = kvm__arch_get_ipa_limit(kvm); + if (!max_ipa_bits) + return 0; + + /* Otherwise, compute the minimal required IPA size */ + max_ipa = ARM_MEMORY_AREA + kvm->cfg.ram_size - 1; + ipa_bits = max(32, fls_long(max_ipa)); + pr_debug("max_ipa %lx ipa_bits %d max_ipa_bits %d", + max_ipa, ipa_bits, max_ipa_bits); + + if (ipa_bits > max_ipa_bits) + die("Memory too large for this system (needs %d bits, %d available)", ipa_bits, max_ipa_bits); + + return KVM_VM_TYPE_ARM_IPA_SIZE(ipa_bits); } -- 2.30.2 _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm