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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 90106C5CFE7 for ; Mon, 9 Jul 2018 17:40:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 56BE0208A2 for ; Mon, 9 Jul 2018 17:40:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 56BE0208A2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934006AbeGIRkv (ORCPT ); Mon, 9 Jul 2018 13:40:51 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:49154 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933795AbeGIRkU (ORCPT ); Mon, 9 Jul 2018 13:40:20 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A762A40201C9; Mon, 9 Jul 2018 17:40:19 +0000 (UTC) Received: from vitty.brq.redhat.com (unknown [10.43.2.155]) by smtp.corp.redhat.com (Postfix) with ESMTP id 17A682156892; Mon, 9 Jul 2018 17:40:17 +0000 (UTC) From: Vitaly Kuznetsov To: x86@kernel.org Cc: "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , "Michael Kelley (EOSG)" , devel@linuxdriverproject.org, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , linux-kernel@vger.kernel.org Subject: [PATCH 2/2] x86/hyper-v: check for VP_INVAL in hyperv_flush_tlb_others() Date: Mon, 9 Jul 2018 19:40:12 +0200 Message-Id: <20180709174012.17429-3-vkuznets@redhat.com> In-Reply-To: <20180709174012.17429-1-vkuznets@redhat.com> References: <20180709174012.17429-1-vkuznets@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Mon, 09 Jul 2018 17:40:19 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Mon, 09 Jul 2018 17:40:19 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'vkuznets@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit 1268ed0c474a ("x86/hyper-v: Fix the circular dependency in IPI enlightenment") pre-filled hv_vp_index with VP_INVAL so it is now (theoretically) possible to observe hv_cpu_number_to_vp_number() returning VP_INVAL. We need to check for that in hyperv_flush_tlb_others(). Not checking for VP_INVAL on the first call site where we do if (hv_cpu_number_to_vp_number(cpumask_last(cpus)) >= 64) goto do_ex_hypercall; is OK, in case we're eligible for non-ex hypercall we'll catch the issue later in for_each_cpu() cycle and in case we'll be doing ex- hypercall cpumask_to_vpset() will fail. It would be nice to change hv_cpu_number_to_vp_number() return value's type to 'u32' but this will likely be a bigger change as all call sites need to be checked first. Fixes: 1268ed0c474a ("x86/hyper-v: Fix the circular dependency in IPI enlightenment") Signed-off-by: Vitaly Kuznetsov --- arch/x86/hyperv/mmu.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/x86/hyperv/mmu.c b/arch/x86/hyperv/mmu.c index 453d2355cd61..1147e1fed7ff 100644 --- a/arch/x86/hyperv/mmu.c +++ b/arch/x86/hyperv/mmu.c @@ -111,6 +111,11 @@ static void hyperv_flush_tlb_others(const struct cpumask *cpus, for_each_cpu(cpu, cpus) { vcpu = hv_cpu_number_to_vp_number(cpu); + if (vcpu == VP_INVAL) { + local_irq_restore(flags); + goto do_native; + } + if (vcpu >= 64) goto do_ex_hypercall; -- 2.14.4