Received: by 2002:ac0:a5a7:0:0:0:0:0 with SMTP id m36-v6csp5462230imm; Sun, 22 Jul 2018 23:20:51 -0700 (PDT) X-Google-Smtp-Source: AAOMgpdPOb44nRvG0DRW6PBVJOxVQg2n14QKhbYnDd3YegKbjQegPWIldCiW0XYu5ak2QfeIahe6 X-Received: by 2002:a62:bd4:: with SMTP id 81-v6mr11951516pfl.67.1532326851008; Sun, 22 Jul 2018 23:20:51 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1532326850; cv=none; d=google.com; s=arc-20160816; b=qZkRtN16wkL3K6JU25n5uQyv0gdKtzH6CohPsqmiPT1VBj0JQn76BBwUKyMx9zZ3ZQ y5zjd+1lyiw2f5MeeytR6MtvBLC/1/uQnvF+XUFHhIs8QoCtuYh62jL0wK57et3OBVlb L/KFvrr/4ytrMvqga7N/5j8BLK++WkijrWPKWTpCbDfOG+2Y+2dlY47vMlapENT/WfUT VMwdQSroPfQVC8ZuUTfjAOruXUItK+9Ezq5vtPBmy/MZOyQBIJLd65EPXS7NYh+jvXkC i3ANDx47ZevE2bQ6aQihLwY0FLKOvXxwbH+FcaTO5y11VZAzyq8wrBKsfyZ7O/sGK3AO sSYA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding :content-language:in-reply-to:mime-version:user-agent:date :message-id:autocrypt:openpgp:from:references:cc:to:subject :arc-authentication-results; bh=n7b+V4QOm85Na0xhVXEgvcFtorxXXzm2Pk8IqBBxPxw=; b=M9psOuvgv9a0ZXL3bq0oDg3Tk7ccUMHFe/KRfbCtTsziwYNxquG9xT/D94IS5+t2yV cf9+gLF/2IKW4NG9ke5H8Nczd31I2X3EKEyYk4RLZU2f6E/85Wsk8WBdnHGIA2blJJiL uWs2GPQHUDUVpH/hpY74xmrZTvhzaugFcgJ8v9aVlB8u+/uSCvP1nmwgouNepYIUuvwF dGQKToT+HOubMqWlpK3uhRP89j+AHSvIeAPOpzb5x8Ki7Bl8FeFGtB/rea/fWtGY3DjX dXCS3LHPlZz0crEJLIy52vDJ4jnKXZIdc66cvRdfDRRKt9sA5ZXhsFK06fkVQiAmi3I1 mRyg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=redhat.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id o7-v6si8045083pga.393.2018.07.22.23.20.36; Sun, 22 Jul 2018 23:20:50 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387892AbeGWHTP (ORCPT + 99 others); Mon, 23 Jul 2018 03:19:15 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:34724 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725976AbeGWHTO (ORCPT ); Mon, 23 Jul 2018 03:19:14 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2DF9740241C7; Mon, 23 Jul 2018 06:19:38 +0000 (UTC) Received: from [10.36.116.129] (ovpn-116-129.ams2.redhat.com [10.36.116.129]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B92E076EF; Mon, 23 Jul 2018 06:19:36 +0000 (UTC) Subject: Re: [PATCH v4 4/6] KVM: X86: Implement PV IPIs send hypercall To: Wanpeng Li Cc: LKML , kvm , Radim Krcmar , Wanpeng Li , Vitaly Kuznetsov References: <1532104133-15777-1-git-send-email-wanpengli@tencent.com> From: Paolo Bonzini Openpgp: preference=signencrypt Autocrypt: addr=pbonzini@redhat.com; prefer-encrypt=mutual; keydata= xsEhBFRCcBIBDqDGsz4K0zZun3jh+U6Z9wNGLKQ0kSFyjN38gMqU1SfP+TUNQepFHb/Gc0E2 CxXPkIBTvYY+ZPkoTh5xF9oS1jqI8iRLzouzF8yXs3QjQIZ2SfuCxSVwlV65jotcjD2FTN04 hVopm9llFijNZpVIOGUTqzM4U55sdsCcZUluWM6x4HSOdw5F5Utxfp1wOjD/v92Lrax0hjiX DResHSt48q+8FrZzY+AUbkUS+Jm34qjswdrgsC5uxeVcLkBgWLmov2kMaMROT0YmFY6A3m1S P/kXmHDXxhe23gKb3dgwxUTpENDBGcfEzrzilWueOeUWiOcWuFOed/C3SyijBx3Av/lbCsHU Vx6pMycNTdzU1BuAroB+Y3mNEuW56Yd44jlInzG2UOwt9XjjdKkJZ1g0P9dwptwLEgTEd3Fo UdhAQyRXGYO8oROiuh+RZ1lXp6AQ4ZjoyH8WLfTLf5g1EKCTc4C1sy1vQSdzIRu3rBIjAvnC tGZADei1IExLqB3uzXKzZ1BZ+Z8hnt2og9hb7H0y8diYfEk2w3R7wEr+Ehk5NQsT2MPI2QBd wEv1/Aj1DgUHZAHzG1QN9S8wNWQ6K9DqHZTBnI1hUlkp22zCSHK/6FwUCuYp1zcAEQEAAc0f UGFvbG8gQm9uemluaSA8Ym9uemluaUBnbnUub3JnPsLBTQQTAQIAIwUCVEJ7AwIbAwcLCQgH AwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJEH4VEAzNNmmxNcwOniaZVLsuy1lW/ntYCA0Caz0i sHpmecK8aWlvL9wpQCk4GlOX9L1emyYXZPmzIYB0IRqmSzAlZxi+A2qm9XOxs5gJ2xqMEXX5 FMtUH3kpkWWJeLqe7z0EoQdUI4EG988uv/tdZyqjUn2XJE+K01x7r3MkUSFz/HZKZiCvYuze VlS0NTYdUt5jBXualvAwNKfxEkrxeHjxgdFHjYWhjflahY7TNRmuqPM/Lx7wAuyoDjlYNE40 Z+Kun4/KjMbjgpcF4Nf3PJQR8qXI6p3so2qsSn91tY7DFSJO6v2HwFJkC2jU95wxfNmTEUZc znXahYbVOwCDJRuPrE5GKFd/XJU9u5hNtr/uYipHij01WXal2cce1S5mn1/HuM1yo1u8xdHy IupCd57EWI948e8BlhpujUCU2tzOb2iYS0kpmJ9/oLVZrOcSZCcCl2P0AaCAsj59z2kwQS9D du0WxUs8waso0Qq6tDEHo8yLCOJDzSz4oojTtWe4zsulVnWV+wu70AioemAT8S6JOtlu60C5 dHgQUD1Tp+ReXpDKXmjbASJx4otvW0qah3o6JaqO79tbDqIvncu3tewwp6c85uZd48JnIOh3 utBAu684nJakbbvZUGikJfxd887ATQRUQnHuAQgAx4dxXO6/Zun0eVYOnr5GRl76+2UrAAem Vv9Yfn2PbDIbxXqLff7oyVJIkw4WdhQIIvvtu5zH24iYjmdfbg8iWpP7NqxUQRUZJEWbx2CR wkMHtOmzQiQ2tSLjKh/cHeyFH68xjeLcinR7jXMrHQK+UCEw6jqi1oeZzGvfmxarUmS0uRuf fAb589AJW50kkQK9VD/9QC2FJISSUDnRC0PawGSZDXhmvITJMdD4TjYrePYhSY4uuIV02v02 8TVAaYbIhxvDY0hUQE4r8ZbGRLn52bEzaIPgl1p/adKfeOUeMReg/CkyzQpmyB1TSk8lDMxQ zCYHXAzwnGi8WU9iuE1P0wARAQABwsEzBBgBAgAJBQJUQnHuAhsMAAoJEH4VEAzNNmmxp1EO oJy0uZggJm7gZKeJ7iUpeX4eqUtqelUw6gU2daz2hE/jsxsTbC/w5piHmk1H1VWDKEM4bQBT uiJ0bfo55SWsUNN+c9hhIX+Y8LEe22izK3w7mRpvGcg+/ZRG4DEMHLP6JVsv5GMpoYwYOmHn plOzCXHvmdlW0i6SrMsBDl9rw4AtIa6bRwWLim1lQ6EM3PWifPrWSUPrPcw4OLSwFk0CPqC4 HYv/7ZnASVkR5EERFF3+6iaaVi5OgBd81F1TCvCX2BEyIDRZLJNvX3TOd5FEN+lIrl26xecz 876SvcOb5SL5SKg9/rCBufdPSjojkGFWGziHiFaYhbuI2E+NfWLJtd+ZvWAAV+O0d8vFFSvr iy9enJ8kxJwhC0ECbSKFY+W1eTIhMD3aeAKY90drozWEyHhENf4l/V+Ja5vOnW+gCDQkGt2Y 1lJAPPSIqZKvHzGShdh8DduC0U3xYkfbGAUvbxeepjgzp0uEnBXfPTy09JGpgWbg0w91GyfT /ujKaGd4vxG2Ei+MMNDmS1SMx7wu0evvQ5kT9NPzyq8R2GIhVSiAd2jioGuTjX6AZCFv3ToO 53DliFMkVTecLptsXaesuUHgL9dKIfvpm+rNXRn9wAwGjk0X/A== Message-ID: <54c97f32-4b56-bfdd-c1a6-614988806ece@redhat.com> Date: Mon, 23 Jul 2018 08:19:35 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Mon, 23 Jul 2018 06:19:38 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Mon, 23 Jul 2018 06:19:38 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'pbonzini@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 23/07/2018 08:10, Wanpeng Li wrote: >>> On 20/07/2018 18:28, Wanpeng Li wrote: >>>> +a0: ipi_bitmap low 64 bits >>>> +a1: ipi_bitmap high 64 bits >>>> +a2: the lowest APIC ID in bitmap >>>> +a3: APIC ICR >>>> + >>>> +The hypercall lets a guest send multicast IPIs at most can handle >>>> +128 vCPUs per hypercall on 64-bit machines and 64 vCPUs per hypercall >>>> +on 32-bit machines. >>>> + >>>> +Returns 0 if successfully delivery the IPIs and 1 if discarded. >>> This description does not mention what happens in 32-bit mode. > Sorry, I think I mentioned "64 vCPUs per hypercall on 32-bit machines" above. Yes, but the description of a0 and a1 is not accurate. Something like a0: lower part of the bitmap of destination APIC IDs a1: higher part of the bitmap of destination APIC IDs .... The hypercall lets a guest send multicast IPIs, with at most 128 128 destinations per hypercall in 64-bit mode and 64 vCPUs per hypercall in 32-bit mode. The destinations are represented by a bitmap contained in the first two arguments (a0 and a1). Bit 0 of a0 corresponds to the APIC ID in the third argument (a2), bit 1 corresponds to the APIC ID a2+1, and so on. Thanks, Paolo