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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7221BC6FA99 for ; Fri, 10 Mar 2023 21:44:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231439AbjCJVom (ORCPT ); Fri, 10 Mar 2023 16:44:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57930 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231895AbjCJVoJ (ORCPT ); Fri, 10 Mar 2023 16:44:09 -0500 Received: from mail-pl1-x64a.google.com (mail-pl1-x64a.google.com [IPv6:2607:f8b0:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 497C66A1D9 for ; Fri, 10 Mar 2023 13:43:19 -0800 (PST) Received: by mail-pl1-x64a.google.com with SMTP id k17-20020a170902d59100b0019abcf45d75so3398101plh.8 for ; Fri, 10 Mar 2023 13:43:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; t=1678484584; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=R1zMC0FqfyEV/0S9ZnbLP+wjU2iwXROZi5JXQooIbHQ=; b=qFNLiBFLLwtMgF+IeChjoCJa+ve1zT5ko/h9MJUHy8G8CX+5NcXD0Y6sTpwQKG+qXP 4NqQn4eVqEyN1HTU7GFiP0F/jBTXTePyXlzK+IWl2IQ6EGzCrtkqnHUUDpWgjSChI0sf lafMTJDPi9IKPx1rvVse3jbOarLoqHrFYV+QEY0OQj5LEG8F18DItVyjpN5xcfAI6RCg lb1AYL8iUu/vqeb6TvGOPRXMRk1NMUUnwF4PPQrqWcmwlrGnqd2UMjgaFilM2hI2dQIa kAQQa4bHO4nfqHbxjuO1rm1hp/ImvvQqskELGWC3DgLpv86gtnF7tdIaG22ZkkjAJjRe 2QFA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1678484584; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=R1zMC0FqfyEV/0S9ZnbLP+wjU2iwXROZi5JXQooIbHQ=; b=jOQMCsaE6f51r4f/gm++L4LkFZJ97Qme3OyEXQF7T/Du8TWMLGoQGDgyBfjVz5uLB9 psqTlQb/ji2KSVfhs/THmqsLz2PfpOzhi9FuKxS6cGTpAY7YRT8HQWk4tr+ds6SP3A4K n6xwFd2KbXTOG3/SfsUMIuqyeV9N3ZCQl1B8N9jcrqeffLUpjDQdlMrjKcXuJsQn0+kl UAxA5iM2Guad2k+vmpt5r/Ia07yqc9EYZLQbfhrHNqcoWQqE+WFBvpp0F1u1K0fkYyyq mfSeywCvNZYeGo++5+6T3LCgYNmRu2DwJlTDy07zbgGjGQgiMQv7ai72ti2fIuLeRTs0 yBVg== X-Gm-Message-State: AO0yUKUkddTEaQzJtkEPJ++xcOv29lUz/NmeMIaJwR9K87S9GniT5Z1b IM4Q/7bwqGjfO8fAvz+k7QIAxDBf5j4= X-Google-Smtp-Source: AK7set8TE4zXGBqQkBmFUJYlcxB6YWIGW3QIa6wDkwV6iROjJa0Me5urReLF/uWyEXu0xpfbwbHaICFKLXE= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a62:d14a:0:b0:592:5eb2:84ea with SMTP id t10-20020a62d14a000000b005925eb284eamr10759214pfl.4.1678484584488; Fri, 10 Mar 2023 13:43:04 -0800 (PST) Reply-To: Sean Christopherson Date: Fri, 10 Mar 2023 13:42:28 -0800 In-Reply-To: <20230310214232.806108-1-seanjc@google.com> Mime-Version: 1.0 References: <20230310214232.806108-1-seanjc@google.com> X-Mailer: git-send-email 2.40.0.rc1.284.g88254d51c5-goog Message-ID: <20230310214232.806108-15-seanjc@google.com> Subject: [PATCH v2 14/18] KVM: SVM: Check that the current CPU supports SVM in kvm_is_svm_supported() From: Sean Christopherson To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Sean Christopherson , Paolo Bonzini Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Andrew Cooper , Kai Huang , Chao Gao Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Check "this" CPU instead of the boot CPU when querying SVM support so that the per-CPU checks done during hardware enabling actually function as intended, i.e. will detect issues where SVM isn't support on all CPUs. Disable migration for the use from svm_init() mostly so that the standard accessors for the per-CPU data can be used without getting yelled at by CONFIG_DEBUG_PREEMPT=y sanity checks. Preventing the "disabled by BIOS" error message from reporting the wrong CPU is largely a bonus, as ensuring a stable CPU during module load is a non-goal for KVM. Link: https://lore.kernel.org/all/ZAdxNgv0M6P63odE@google.com Cc: Kai Huang Cc: Chao Gao Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/svm.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 2934f185960d..f04b61c3d9d8 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -520,18 +520,20 @@ static void svm_init_osvw(struct kvm_vcpu *vcpu) vcpu->arch.osvw.status |= 1; } -static bool kvm_is_svm_supported(void) +static bool __kvm_is_svm_supported(void) { - int cpu = raw_smp_processor_id(); + int cpu = smp_processor_id(); + struct cpuinfo_x86 *c = &cpu_data(cpu); + u64 vm_cr; - if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD && - boot_cpu_data.x86_vendor != X86_VENDOR_HYGON) { + if (c->x86_vendor != X86_VENDOR_AMD && + c->x86_vendor != X86_VENDOR_HYGON) { pr_err("CPU %d isn't AMD or Hygon\n", cpu); return false; } - if (!boot_cpu_has(X86_FEATURE_SVM)) { + if (!cpu_has(c, X86_FEATURE_SVM)) { pr_err("SVM not supported by CPU %d\n", cpu); return false; } @@ -550,9 +552,20 @@ static bool kvm_is_svm_supported(void) return true; } +static bool kvm_is_svm_supported(void) +{ + bool supported; + + migrate_disable(); + supported = __kvm_is_svm_supported(); + migrate_enable(); + + return supported; +} + static int svm_check_processor_compat(void) { - if (!kvm_is_svm_supported()) + if (!__kvm_is_svm_supported()) return -EIO; return 0; -- 2.40.0.rc1.284.g88254d51c5-goog