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=-15.8 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 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 777BAC43603 for ; Wed, 31 Mar 2021 12:42:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5657E619C1 for ; Wed, 31 Mar 2021 12:42:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235681AbhCaMmR (ORCPT ); Wed, 31 Mar 2021 08:42:17 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:55641 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235618AbhCaMln (ORCPT ); Wed, 31 Mar 2021 08:41:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617194502; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=H7dNXYaOTclqUn9MijXwZ7hg6tnWG/YqlnOo2zWP1Ro=; b=QMFkUeM3/FhzJ3hVyDmAsSxF/Hat94myuKhCr5lPpMnl+/uBDo/s1sQmlqw1sXEAXQRrkb 1ImL4e3CUAbEXiGyscm2WWOb5rUxdl/SXkylcYObFABms0JAWv41hDvDg0xA6KrSGrAlIL uOl5paXvDlnP7mZWCSUfvmr1vvbfJ2k= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-238-YZromXsBOru0T6J7NaNcQA-1; Wed, 31 Mar 2021 08:41:41 -0400 X-MC-Unique: YZromXsBOru0T6J7NaNcQA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 14270108BD0C; Wed, 31 Mar 2021 12:41:40 +0000 (UTC) Received: from vitty.brq.redhat.com (unknown [10.40.193.13]) by smtp.corp.redhat.com (Postfix) with ESMTP id 01E9B60861; Wed, 31 Mar 2021 12:41:37 +0000 (UTC) From: Vitaly Kuznetsov To: kvm@vger.kernel.org, Paolo Bonzini Cc: Sean Christopherson , Wanpeng Li , Jim Mattson , Marcelo Tosatti , linux-kernel@vger.kernel.org Subject: [PATCH v3 2/2] selftests: kvm: Check that TSC page value is small after KVM_SET_CLOCK(0) Date: Wed, 31 Mar 2021 14:41:30 +0200 Message-Id: <20210331124130.337992-3-vkuznets@redhat.com> In-Reply-To: <20210331124130.337992-1-vkuznets@redhat.com> References: <20210331124130.337992-1-vkuznets@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a test for the issue when KVM_SET_CLOCK(0) call could cause TSC page value to go very big because of a signedness issue around hv_clock->system_time. Signed-off-by: Vitaly Kuznetsov --- tools/testing/selftests/kvm/x86_64/hyperv_clock.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_clock.c b/tools/testing/selftests/kvm/x86_64/hyperv_clock.c index ffbc4555c6e2..7f1d2765572c 100644 --- a/tools/testing/selftests/kvm/x86_64/hyperv_clock.c +++ b/tools/testing/selftests/kvm/x86_64/hyperv_clock.c @@ -80,19 +80,24 @@ static inline void check_tsc_msr_rdtsc(void) GUEST_ASSERT(delta_ns * 100 < (t2 - t1) * 100); } +static inline u64 get_tscpage_ts(struct ms_hyperv_tsc_page *tsc_page) +{ + return mul_u64_u64_shr64(rdtsc(), tsc_page->tsc_scale) + tsc_page->tsc_offset; +} + static inline void check_tsc_msr_tsc_page(struct ms_hyperv_tsc_page *tsc_page) { u64 r1, r2, t1, t2; /* Compare TSC page clocksource with HV_X64_MSR_TIME_REF_COUNT */ - t1 = mul_u64_u64_shr64(rdtsc(), tsc_page->tsc_scale) + tsc_page->tsc_offset; + t1 = get_tscpage_ts(tsc_page); r1 = rdmsr(HV_X64_MSR_TIME_REF_COUNT); /* 10 ms tolerance */ GUEST_ASSERT(r1 >= t1 && r1 - t1 < 100000); nop_loop(); - t2 = mul_u64_u64_shr64(rdtsc(), tsc_page->tsc_scale) + tsc_page->tsc_offset; + t2 = get_tscpage_ts(tsc_page); r2 = rdmsr(HV_X64_MSR_TIME_REF_COUNT); GUEST_ASSERT(r2 >= t1 && r2 - t2 < 100000); } @@ -130,7 +135,11 @@ static void guest_main(struct ms_hyperv_tsc_page *tsc_page, vm_paddr_t tsc_page_ tsc_offset = tsc_page->tsc_offset; /* Call KVM_SET_CLOCK from userspace, check that TSC page was updated */ + GUEST_SYNC(7); + /* Sanity check TSC page timestamp, it should be close to 0 */ + GUEST_ASSERT(get_tscpage_ts(tsc_page) < 100000); + GUEST_ASSERT(tsc_page->tsc_offset != tsc_offset); nop_loop(); -- 2.30.2