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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 181E9C3F2CD for ; Fri, 28 Feb 2020 15:33:17 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D804A246A0 for ; Fri, 28 Feb 2020 15:33:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="XpxSaF/h" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D804A246A0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:48410 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j7hdb-0007mm-V2 for qemu-devel@archiver.kernel.org; Fri, 28 Feb 2020 10:33:15 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:46061) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j7hck-0007HV-Qh for qemu-devel@nongnu.org; Fri, 28 Feb 2020 10:32:23 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j7hcj-0002Tr-IW for qemu-devel@nongnu.org; Fri, 28 Feb 2020 10:32:22 -0500 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:56913 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j7hcj-0002TB-Eg for qemu-devel@nongnu.org; Fri, 28 Feb 2020 10:32:21 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1582903940; 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=TTH9m8PggH+3DGdwQCXfDdDc88/rumaRVKwk3IX1S80=; b=XpxSaF/hTMQOVZERZqcdGSnCiwT+IG5WTXRCKtw0q8uo2jqg1/73xhf3i/RDogSY6pppnz b98MSsHkO9CtDV4BXyfFQ+0JKj9co7jffOO0Ylw4PO7ZV6GvQEkolqKVrh/M/dY3/oNPWG zjAnMl4f0tt4LHVq34ZwQSbw6S6EpdY= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-432-q7xO_BV0Oyawyf6tw7anSQ-1; Fri, 28 Feb 2020 10:32:19 -0500 X-MC-Unique: q7xO_BV0Oyawyf6tw7anSQ-1 Received: by mail-wr1-f69.google.com with SMTP id p8so1498052wrw.5 for ; Fri, 28 Feb 2020 07:32:18 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=TTH9m8PggH+3DGdwQCXfDdDc88/rumaRVKwk3IX1S80=; b=YLGOAlWmjA6IZNzL4aYvkTw98DygBEZHN7zmSpwVy/eb0Znna2GKLRfT1zYs/0BnWa +2NsxOhOJtR1zDJzU3DvhN1RtF/JGDGa6ZWeeiIVcyX7YVnF4HFlGEN9BiZEgNGk0sB9 wVtC0V+5TqIOivUEeJnGt01aB/iJu3CWwpRfglrZbZd1YxwyvcivhPS9baj6bCo3YGlo EdO8zLSDBZ1e0Bxj+QppDxNOvmnU/53msfYkoqIykEzu8/tyEKFfIgHTA06KpV9ezzGJ GC1A0drhTN8bjCgWBTmK9npiQY68RDe8CGXA25zWVA9Oe0H+zqZ8nl1jpGN2nFZSOkQ6 flVA== X-Gm-Message-State: APjAAAUgWaP6Le75kSvpae9ogKKKGw6DXlwj4sFd567lSoUWQK719JyL 61WC2wM+zgzmX7mhLlofkCZ+sXJhMvnnixi1/UD/zNXgjZl5Y8ZpdUD8aa/9cYZfhhKIlkdqqMi Q2p1FCINhPH58NdE= X-Received: by 2002:a1c:f606:: with SMTP id w6mr5266473wmc.109.1582903937800; Fri, 28 Feb 2020 07:32:17 -0800 (PST) X-Google-Smtp-Source: APXvYqwuedhZCVfQip0bkuaoBNFXehxKaPAOSpwwDFim2R+FbSxN6mrtzR08xWUJBOB5Ja1IQjPKlg== X-Received: by 2002:a1c:f606:: with SMTP id w6mr5266460wmc.109.1582903937553; Fri, 28 Feb 2020 07:32:17 -0800 (PST) Received: from [192.168.178.40] ([151.20.130.54]) by smtp.gmail.com with ESMTPSA id g14sm13625962wrv.58.2020.02.28.07.32.16 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 28 Feb 2020 07:32:16 -0800 (PST) Subject: Re: [PATCH 0/5] vfio/pci: Fix up breakage against split irqchip and INTx To: Peter Xu References: <20200226225048.216508-1-peterx@redhat.com> <20200228152511.GS180973@xz-x1> From: Paolo Bonzini Message-ID: <2e89d12e-2a83-aea6-6c8f-a076ac01ebe5@redhat.com> Date: Fri, 28 Feb 2020 16:32:15 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200228152511.GS180973@xz-x1> Content-Language: en-US X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.61 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eric Auger , Alex Williamson , Cornelia Huck , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 28/02/20 16:25, Peter Xu wrote: > My current thought is that we keep this hackery in userspace only so > we keep split+resamplefd forbidden in the kernel and be clean there. It is better, yes. The kernel solution makes some sense because split irqchip _does_ have a concept of ioapic GSIs and routes. But the kernel patch would not fix the fact that remote-irr remains zero, which would need a userspace change anyway. Paolo