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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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 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 3B836C04FF3 for ; Mon, 24 May 2021 20:01:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 16D956140A for ; Mon, 24 May 2021 20:01:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233122AbhEXUDQ (ORCPT ); Mon, 24 May 2021 16:03:16 -0400 Received: from smtp-fw-9103.amazon.com ([207.171.188.200]:27263 "EHLO smtp-fw-9103.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232829AbhEXUDQ (ORCPT ); Mon, 24 May 2021 16:03:16 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.de; i=@amazon.de; q=dns/txt; s=amazon201209; t=1621886508; x=1653422508; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version; bh=xpGv7I/JVbWk3gCMlwhBWH3s3VAIfzbRaEG/9eDRB2o=; b=Ba/L+qNyQbscZNbkksQWky5fW4FX2HUtuSCq35nDjZ0BdJELwBy1W4NP 7SWTSQjWpxQ0E9paeBp67OgMDA5AjizEz9vMuvvJHedqZDnUGIXdTxcsb LajK1kDi+zkJ85LKsmK5II+gdrKW1Of3U9t0IUuFrMOD6alnlPFncM2vt Q=; X-IronPort-AV: E=Sophos;i="5.82,325,1613433600"; d="scan'208";a="934796182" Received: from pdx4-co-svc-p1-lb2-vlan3.amazon.com (HELO email-inbound-relay-1e-c7f73527.us-east-1.amazon.com) ([10.25.36.214]) by smtp-border-fw-9103.sea19.amazon.com with ESMTP; 24 May 2021 20:01:47 +0000 Received: from EX13D28EUC003.ant.amazon.com (iad12-ws-svc-p26-lb9-vlan3.iad.amazon.com [10.40.163.38]) by email-inbound-relay-1e-c7f73527.us-east-1.amazon.com (Postfix) with ESMTPS id 1C54EA06B4; Mon, 24 May 2021 20:01:45 +0000 (UTC) Received: from uc8bbc9586ea454.ant.amazon.com (10.43.160.110) by EX13D28EUC003.ant.amazon.com (10.43.164.43) with Microsoft SMTP Server (TLS) id 15.0.1497.18; Mon, 24 May 2021 20:01:41 +0000 From: Siddharth Chandrasekaran To: Paolo Bonzini , Marcelo Tosatti CC: Siddharth Chandrasekaran , Siddharth Chandrasekaran , Alexander Graf , Evgeny Iakovlev , Liran Alon , Ioannis Aslanidis , , Subject: [PATCH 5/6] kvm/i386: Add support for user space MSR filtering Date: Mon, 24 May 2021 22:01:20 +0200 Message-ID: <4c7ecaab0295e8420ee03baf37c7722e01bb81ce.1621885749.git.sidcha@amazon.de> X-Mailer: git-send-email 2.17.1 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.43.160.110] X-ClientProxiedBy: EX13D22UWC001.ant.amazon.com (10.43.162.192) To EX13D28EUC003.ant.amazon.com (10.43.164.43) Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Check and enable user space MSR filtering capability and handle new exit reason KVM_EXIT_X86_WRMSR. This will be used in a follow up patch to implement hyper-v overlay pages. Signed-off-by: Siddharth Chandrasekaran --- target/i386/kvm/kvm.c | 72 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index 362f04ab3f..3591f8cecc 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -117,6 +117,8 @@ static bool has_msr_ucode_rev; static bool has_msr_vmx_procbased_ctls2; static bool has_msr_perf_capabs; static bool has_msr_pkrs; +static bool has_msr_filtering; +static bool msr_filters_active; static uint32_t has_architectural_pmu_version; static uint32_t num_architectural_pmu_gp_counters; @@ -2138,6 +2140,57 @@ static void register_smram_listener(Notifier *n, void *unused) &smram_address_space, 1); } +static void kvm_set_msr_filter_range(struct kvm_msr_filter_range *range, uint32_t flags, + uint32_t base, uint32_t nmsrs, ...) +{ + int i, filter_to_userspace; + va_list ap; + + range->flags = flags; + range->nmsrs = nmsrs; + range->base = base; + + va_start(ap, nmsrs); + for (i = 0; i < nmsrs; i++) { + filter_to_userspace = va_arg(ap, int); + if (!filter_to_userspace) { + range->bitmap[i / 8] = 1 << (i % 8); + } + } + va_end(ap); +} + +static int kvm_set_msr_filters(KVMState *s) +{ + int r, nmsrs, nfilt = 0, bitmap_pos = 0; + struct kvm_msr_filter filter = { }; + struct kvm_msr_filter_range *range; + uint8_t bitmap_buf[KVM_MSR_FILTER_MAX_RANGES * 8] = {0}; + + filter.flags = KVM_MSR_FILTER_DEFAULT_ALLOW; + + if (has_hyperv) { + /* Hyper-V overlay page MSRs */ + nmsrs = 2; + range = &filter.ranges[nfilt++]; + range->bitmap = &bitmap_buf[bitmap_pos]; + kvm_set_msr_filter_range(range, KVM_MSR_FILTER_WRITE, + HV_X64_MSR_GUEST_OS_ID, nmsrs, + true, /* HV_X64_MSR_GUEST_OS_ID */ + true /* HV_X64_MSR_HYPERCALL */); + bitmap_pos += ROUND_UP(nmsrs, 8) / 8; + assert(bitmap_pos < sizeof(bitmap_buf)); + } + + r = kvm_vm_ioctl(s, KVM_X86_SET_MSR_FILTER, &filter); + if (r != 0) { + error_report("kvm: failed to set MSR filters"); + return -1; + } + + return 0; +} + int kvm_arch_init(MachineState *ms, KVMState *s) { uint64_t identity_base = 0xfffbc000; @@ -2269,6 +2322,17 @@ int kvm_arch_init(MachineState *ms, KVMState *s) } } + has_msr_filtering = kvm_check_extension(s, KVM_CAP_X86_USER_SPACE_MSR) && + kvm_check_extension(s, KVM_CAP_X86_MSR_FILTER); + if (has_msr_filtering) { + ret = kvm_vm_enable_cap(s, KVM_CAP_X86_USER_SPACE_MSR, 0, + KVM_MSR_EXIT_REASON_FILTER); + if (ret == 0) { + ret = kvm_set_msr_filters(s); + msr_filters_active = (ret == 0); + } + } + return 0; } @@ -4542,6 +4606,11 @@ static bool host_supports_vmx(void) return ecx & CPUID_EXT_VMX; } +static int kvm_handle_wrmsr(X86CPU *cpu, struct kvm_run *run) +{ + return 0; +} + #define VMX_INVALID_GUEST_STATE 0x80000021 int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run) @@ -4600,6 +4669,9 @@ int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run) ioapic_eoi_broadcast(run->eoi.vector); ret = 0; break; + case KVM_EXIT_X86_WRMSR: + ret = kvm_handle_wrmsr(cpu, run); + break; default: fprintf(stderr, "KVM: unknown exit reason %d\n", run->exit_reason); ret = -1; -- 2.17.1 Amazon Development Center Germany GmbH Krausenstr. 38 10117 Berlin Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B Sitz: Berlin Ust-ID: DE 289 237 879