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=-0.9 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 9363CC65BAF for ; Wed, 12 Dec 2018 17:43:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4FBC32080F for ; Wed, 12 Dec 2018 17:43:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4FBC32080F 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 S1728013AbeLLRn1 (ORCPT ); Wed, 12 Dec 2018 12:43:27 -0500 Received: from mx1.redhat.com ([209.132.183.28]:16168 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726922AbeLLRn0 (ORCPT ); Wed, 12 Dec 2018 12:43:26 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4C24CC070477; Wed, 12 Dec 2018 17:43:26 +0000 (UTC) Received: from vitty.brq.redhat.com.redhat.com (unknown [10.43.2.155]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0128B600CC; Wed, 12 Dec 2018 17:43:23 +0000 (UTC) From: Vitaly Kuznetsov To: kvm@vger.kernel.org Cc: Paolo Bonzini , Radim =?utf-8?B?S3LEjW3DocWZ?= , linux-kernel@vger.kernel.org, Roman Kagan , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , x86@kernel.org, "Michael Kelley \(EOSG\)" , Nadav Amit , Thomas Gleixner Subject: Re: [PATCH v3] x86/hyper-v: Mark TLFS structures packed In-Reply-To: <20181203140636.21912-1-vkuznets@redhat.com> References: <20181203140636.21912-1-vkuznets@redhat.com> Date: Wed, 12 Dec 2018 18:43:23 +0100 Message-ID: <87mupa4p50.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Wed, 12 Dec 2018 17:43:26 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Vitaly Kuznetsov writes: > /* Define virtual processor assist page structure. */ > struct hv_vp_assist_page { > @@ -519,7 +519,7 @@ struct hv_vp_assist_page { > __u64 nested_enlightenments_control[2]; > __u32 enlighten_vmentry; > __u64 current_nested_vmcs; > -}; > +} __packed; > This particular structure wasn't properly padded: u32 padding is missing between 'enlighten_vmentry' and 'current_nested_vmcs'. > struct hv_enlightened_vmcs { > u32 revision_id; > @@ -693,7 +693,7 @@ struct hv_enlightened_vmcs { > u32 nested_flush_hypercall:1; > u32 msr_bitmap:1; > u32 reserved:30; > - } hv_enlightenments_control; > + } __packed hv_enlightenments_control; > u32 hv_vp_id; > > u64 hv_vm_id; > @@ -703,7 +703,7 @@ struct hv_enlightened_vmcs { > u64 padding64_5[7]; > u64 xss_exit_bitmap; > u64 padding64_6[7]; > -}; > +} __packed; struct hv_enlightened_vmcs also has a hole: we need an u16 padding after 'u16 host_tr_selector'. Both these problems led to Enlightened VMCS for Hyper-V on KVM being completely broken. As this is not yet merged, v4 is coming to rescue! -- Vitaly