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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 741CAC83013 for ; Wed, 2 Dec 2020 18:44:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26DE2206D5 for ; Wed, 2 Dec 2020 18:44:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387914AbgLBSn4 (ORCPT ); Wed, 2 Dec 2020 13:43:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54050 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389627AbgLBSno (ORCPT ); Wed, 2 Dec 2020 13:43:44 -0500 Received: from mail-wm1-x343.google.com (mail-wm1-x343.google.com [IPv6:2a00:1450:4864:20::343]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 529EAC094257 for ; Wed, 2 Dec 2020 10:42:28 -0800 (PST) Received: by mail-wm1-x343.google.com with SMTP id k10so10127502wmi.3 for ; Wed, 02 Dec 2020 10:42:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=26Ee3tSf6bjWmO+pbW0InldfONK6QPnrCLx1QjKfx/Q=; b=Nu9UWjvhl68YCUsjhbXmp2EFwXOEzYW/jis6nLNCXn/NxJfU7CpOTssijMFw+UsPpd 7oltSpuibe/iHjGG2OpFQ4w4pD1qsmbBGRvFmjW2xuUn2JkuWyVwcg85RRjAp9tIXaTK aP2gAH/bBPYSxRqNlX8Plyl8Gky8pnctQ4ag/a3FWSbjY3S0k6kIfS78g+wEMf0OxlFk v65pBZ5UKBi8p2sRqdfPUqIc6NexyNIU1+i7sK09E/pPGsQ7wP233KAe1++CSZzOLErg 61rDJ75t8vNUKCFB/8Anz2tYqOdXv+9jzvHcdxm4tMFqEUh2BjkE8mApOYf3gCbWJHkp jjPw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=26Ee3tSf6bjWmO+pbW0InldfONK6QPnrCLx1QjKfx/Q=; b=S5dw2uFd6XnDbzH+DvTUMuU64h13nx9D6S8mT9DyXQ138MfimRLwqOdP1Q/vrTw6kG clxgRj8+3gZtSVWcjfsc9z4eCoRL1yQ3pnMjW1W0sF5ikLnWTAY4B9Cjr/oABsEWmHmc OG5tYmvwBOHAbcMzeuMLCmuQ2ZJ2v2Eyb14qQMcBRbDVa6QHmVsbJ0hq3kOz6qBB6QOS DrFndXNvBWo5QOPJyeCufI8DNKVz8l7a6EEbniuVN7B0ONVftw0sjMbe1gNkRLweEVUR jfw8QAaFZvnmf+OMZEgtyLvsgOConT5C81dKgpLUzMVmjPw1D+LV+ElvV9x0ED3mjK/m TCIg== X-Gm-Message-State: AOAM530OiFo4wdX0UNj4JZtEiysxDUOcQD/Ky9f5fEzpwgtOI5Dsj5ar QK26pkKbqlTb8B0qWiXYs+kJcw== X-Google-Smtp-Source: ABdhPJxp6dGVemgWiRIwNDXC1BFMQeJwThH7w+RQVGXX/e/0zonlc4l4p1zCzJtr2NzkM2SO9rchMQ== X-Received: by 2002:a1c:220a:: with SMTP id i10mr4451281wmi.93.1606934546855; Wed, 02 Dec 2020 10:42:26 -0800 (PST) Received: from localhost ([2a01:4b00:8523:2d03:5ddd:b7c5:e3c9:e87a]) by smtp.gmail.com with ESMTPSA id q12sm3056403wmc.45.2020.12.02.10.42.25 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 02 Dec 2020 10:42:25 -0800 (PST) From: David Brazdil To: kvmarm@lists.cs.columbia.edu Cc: Jonathan Corbet , Catalin Marinas , Will Deacon , Marc Zyngier , James Morse , Julien Thierry , Suzuki K Poulose , Dennis Zhou , Tejun Heo , Christoph Lameter , Mark Rutland , Lorenzo Pieralisi , Sudeep Holla , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kernel-team@android.com, David Brazdil Subject: [PATCH v4 26/26] kvm: arm64: Fix EL2 mode availability checks Date: Wed, 2 Dec 2020 18:41:22 +0000 Message-Id: <20201202184122.26046-27-dbrazdil@google.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201202184122.26046-1-dbrazdil@google.com> References: <20201202184122.26046-1-dbrazdil@google.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org With protected nVHE hyp code interception host's PSCI SMCs, the host starts seeing new CPUs boot in EL1 instead of EL2. The kernel logic that keeps track of the boot mode needs to be adjusted. Add a static key enabled if KVM protected mode initialization is successful. When the key is enabled, is_hyp_mode_available continues to report `true` because its users either treat it as a check whether KVM will be / was initialized, or whether stub HVCs can be made (eg. hibernate). is_hyp_mode_mismatched is changed to report `false` when the key is enabled. That's because all cores' modes matched at the point of KVM init and KVM will not allow cores not present at init to boot. That said, the function is never used after KVM is initialized. Signed-off-by: David Brazdil --- arch/arm64/include/asm/virt.h | 18 ++++++++++++++++++ arch/arm64/kvm/arm.c | 9 ++++++--- 2 files changed, 24 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/virt.h b/arch/arm64/include/asm/virt.h index eb81dcc220b6..ee6a48df89d9 100644 --- a/arch/arm64/include/asm/virt.h +++ b/arch/arm64/include/asm/virt.h @@ -65,9 +65,19 @@ extern u32 __boot_cpu_mode[2]; void __hyp_set_vectors(phys_addr_t phys_vector_base); void __hyp_reset_vectors(void); +DECLARE_STATIC_KEY_FALSE(kvm_protected_mode_initialized); + /* Reports the availability of HYP mode */ static inline bool is_hyp_mode_available(void) { + /* + * If KVM protected mode is initialized, all CPUs must have been booted + * in EL2. Avoid checking __boot_cpu_mode as CPUs now come up in EL1. + */ + if (IS_ENABLED(CONFIG_KVM) && + static_branch_likely(&kvm_protected_mode_initialized)) + return true; + return (__boot_cpu_mode[0] == BOOT_CPU_MODE_EL2 && __boot_cpu_mode[1] == BOOT_CPU_MODE_EL2); } @@ -75,6 +85,14 @@ static inline bool is_hyp_mode_available(void) /* Check if the bootloader has booted CPUs in different modes */ static inline bool is_hyp_mode_mismatched(void) { + /* + * If KVM protected mode is initialized, all CPUs must have been booted + * in EL2. Avoid checking __boot_cpu_mode as CPUs now come up in EL1. + */ + if (IS_ENABLED(CONFIG_KVM) && + static_branch_likely(&kvm_protected_mode_initialized)) + return false; + return __boot_cpu_mode[0] != __boot_cpu_mode[1]; } diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 5f8776eefe46..6e637d2b4cfb 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -47,6 +47,7 @@ __asm__(".arch_extension virt"); #endif static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT; +DEFINE_STATIC_KEY_FALSE(kvm_protected_mode_initialized); DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector); @@ -1926,12 +1927,14 @@ int kvm_arch_init(void *opaque) if (err) goto out_hyp; - if (is_protected_kvm_enabled()) + if (is_protected_kvm_enabled()) { + static_branch_enable(&kvm_protected_mode_initialized); kvm_info("Protected nVHE mode initialized successfully\n"); - else if (in_hyp_mode) + } else if (in_hyp_mode) { kvm_info("VHE mode initialized successfully\n"); - else + } else { kvm_info("Hyp mode initialized successfully\n"); + } return 0; -- 2.29.2.454.gaff20da3a2-goog