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=-11.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 15554C433DF for ; Mon, 20 Jul 2020 04:19:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E07BB20758 for ; Mon, 20 Jul 2020 04:19:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Th5aOFzF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726084AbgGTETy (ORCPT ); Mon, 20 Jul 2020 00:19:54 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:54218 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725774AbgGTETx (ORCPT ); Mon, 20 Jul 2020 00:19:53 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595218792; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=04wRZDzfAbjzY24AOQSUyoqCb/wNOPZL7NBzxLPbzVc=; b=Th5aOFzFuuITP3XQy8b+7s/gwxOp6ibKciGcBdhxuaggEZQQIIZ2LvVSBlyk9mb7L3LwMk +LtKXIAnzx2+UUHUn2LCKtxC/u1OwLylpLp8ZC/YeR4gdxjfCVdGrCk3SM+zZ55M62tzAo 5Dd8oSA5qMCTdp7oeLthLSl3r+5WyIs= 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-84-9KzyVAvVO_aogPSdmTB61Q-1; Mon, 20 Jul 2020 00:19:51 -0400 X-MC-Unique: 9KzyVAvVO_aogPSdmTB61Q-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6FF53107ACCA; Mon, 20 Jul 2020 04:19:49 +0000 (UTC) Received: from [10.72.13.139] (ovpn-13-139.pek2.redhat.com [10.72.13.139]) by smtp.corp.redhat.com (Postfix) with ESMTP id B12925C1B2; Mon, 20 Jul 2020 04:19:38 +0000 (UTC) Subject: Re: [PATCH V2 2/6] kvm: detect assigned device via irqbypass manager To: Alex Williamson , Zhu Lingshan Cc: mst@redhat.com, pbonzini@redhat.com, sean.j.christopherson@intel.com, wanpengli@tencent.com, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, kvm@vger.kernel.org References: <1594898629-18790-1-git-send-email-lingshan.zhu@intel.com> <1594898629-18790-3-git-send-email-lingshan.zhu@intel.com> <20200717120821.3c2a56db@x1.home> From: Jason Wang Message-ID: Date: Mon, 20 Jul 2020 12:19:37 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200717120821.3c2a56db@x1.home> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 2020/7/18 上午2:08, Alex Williamson wrote: > On Thu, 16 Jul 2020 19:23:45 +0800 > Zhu Lingshan wrote: > >> vDPA devices has dedicated backed hardware like >> passthrough-ed devices. Then it is possible to setup irq >> offloading to vCPU for vDPA devices. Thus this patch tries to >> manipulated assigned device counters via irqbypass manager. >> >> We will increase/decrease the assigned device counter in kvm/x86. >> Both vDPA and VFIO would go through this code path. >> >> This code path only affect x86 for now. >> >> Signed-off-by: Zhu Lingshan >> Suggested-by: Jason Wang >> --- >> arch/x86/kvm/x86.c | 10 ++++++++-- >> 1 file changed, 8 insertions(+), 2 deletions(-) >> >> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c >> index 00c88c2..20c07d3 100644 >> --- a/arch/x86/kvm/x86.c >> +++ b/arch/x86/kvm/x86.c >> @@ -10624,11 +10624,17 @@ int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, >> { >> struct kvm_kernel_irqfd *irqfd = >> container_of(cons, struct kvm_kernel_irqfd, consumer); >> + int ret; >> >> irqfd->producer = prod; >> + kvm_arch_start_assignment(irqfd->kvm); >> + ret = kvm_x86_ops.update_pi_irte(irqfd->kvm, >> + prod->irq, irqfd->gsi, 1); >> + >> + if (ret) >> + kvm_arch_end_assignment(irqfd->kvm); >> >> - return kvm_x86_ops.update_pi_irte(irqfd->kvm, >> - prod->irq, irqfd->gsi, 1); >> + return ret; >> } >> >> void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, > > Why isn't there a matching end-assignment in the del_producer path? It > seems this only goes one-way, what happens when a device is > hot-unplugged from the VM or the device interrupt configuration changes. > This will still break vfio if it's not guaranteed to be symmetric. > Thanks, > > Alex Yes, we need add logic in the del_producer path. Thanks