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=-2.0 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 4D145C33CA2 for ; Thu, 9 Jan 2020 15:44:12 +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 1AF2E2067D for ; Thu, 9 Jan 2020 15:44:12 +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="Bry8Nq4p" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1AF2E2067D 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]:34424 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ipZyl-0003i8-8F for qemu-devel@archiver.kernel.org; Thu, 09 Jan 2020 10:44:11 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:53734) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ipZsx-0003X9-PB for qemu-devel@nongnu.org; Thu, 09 Jan 2020 10:38:12 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ipZsv-0002rK-UE for qemu-devel@nongnu.org; Thu, 09 Jan 2020 10:38:10 -0500 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:41425 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ipZsv-0002kO-Ni for qemu-devel@nongnu.org; Thu, 09 Jan 2020 10:38:09 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1578584288; 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=WehvuzyeF8mf2IdWbytmu7J2YOAFixUN4rzh0E4cOu0=; b=Bry8Nq4phkMDpvCWNKSgLgEd5jjOaC6BkF8VtVAFHctde+J64nEXJnlB5YpMcrQJkyArzl jKpuJKYAsEkGkF5wCe13tptRVVe5Dfrax4kMuQuWP/v2NGnaQxm1iRFzde/6Xn7ojw/Azw 8xaE4S9qP2JCWiRzRYdweUttPbrQjLI= 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-196-sosroMSPNmCKXDH1KY4oXw-1; Thu, 09 Jan 2020 10:38:07 -0500 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 37433CF98E for ; Thu, 9 Jan 2020 15:38:06 +0000 (UTC) Received: from work-vm (unknown [10.36.118.29]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B4726385; Thu, 9 Jan 2020 15:38:02 +0000 (UTC) Date: Thu, 9 Jan 2020 15:38:00 +0000 From: "Dr. David Alan Gilbert" To: Paolo Bonzini Subject: Re: [PATCH 2/2] hyperv/synic: Allocate as ram_device Message-ID: <20200109153800.GJ6795@work-vm> References: <20200108135353.75471-1-dgilbert@redhat.com> <20200108135353.75471-3-dgilbert@redhat.com> <20200109064527-mutt-send-email-mst@kernel.org> <20200109120820.GB6795@work-vm> <20200109071454-mutt-send-email-mst@kernel.org> <20200109122237.GD6795@work-vm> <20200109080412-mutt-send-email-mst@kernel.org> <20200109132242.GF6795@work-vm> <3162676e-da40-7a3f-1777-2ed4f3efffe1@redhat.com> MIME-Version: 1.0 In-Reply-To: <3162676e-da40-7a3f-1777-2ed4f3efffe1@redhat.com> User-Agent: Mutt/1.13.0 (2019-11-30) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: sosroMSPNmCKXDH1KY4oXw-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 205.139.110.120 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: jasowang@redhat.com, vkuznets@redhat.com, qemu-devel@nongnu.org, "Michael S. Tsirkin" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Paolo Bonzini (pbonzini@redhat.com) wrote: > On 09/01/20 14:22, Dr. David Alan Gilbert wrote: > > * Michael S. Tsirkin (mst@redhat.com) wrote: > >> On Thu, Jan 09, 2020 at 12:22:37PM +0000, Dr. David Alan Gilbert wrote= : > >>> Do we want a new memory_region_init for that or just to be able to ad= d > >>> a flag? > >>> > >> I think a flag API is preferable since this can apply to any kind of > >> region. But can go either way, Paolo's the maintainer there. > >=20 > > (Copying Paolo in) > > So what exactly does this flag mean; to me it's 'no vhost' - but is it > > actually more general? >=20 > It has two more effects in addition to no vhost: >=20 > 1) it is skipped when dumping the guest (is this a good or bad idea for > SynIC?) >=20 > 2) accesses to the region will use the specified size (e.g. 4-bytes for > address_space_stl, 1-byte for address_space_stb) instead of a memcpy. > Doesn't really matter for SynIC regions. >=20 > If (1) is a good idea, then it's 2 out of 3 and I guess the patch is okay= . It's probably best to keep them in the dump because they give some info on the current state of the windows guest and interrupts. Also, as Roman points out the ram-device pages aren't migrated, so we need to fix that as well. So, do we add a new flag? If so, is no-vhost what we want? Dave > Paolo >=20 -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK