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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id EF810E74902 for ; Mon, 2 Oct 2023 18:25:32 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qnNal-0002ev-Jv; Mon, 02 Oct 2023 14:24:30 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qnNaj-0002eh-32 for qemu-devel@nongnu.org; Mon, 02 Oct 2023 14:24:25 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qnNah-0000xb-6i for qemu-devel@nongnu.org; Mon, 02 Oct 2023 14:24:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1696271062; 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=3/87R/qdS3pNHN03Idtk7DYzSvfmsvgBHhDUOh/TSU4=; b=X8NrkquClS1dqCQJB1sMjnrwH1f4FY9jC4atQ2hsd987JxCFEJGyiCoJiIP0HtjsabFekY O9CMgE2rXFvuSa3elP09BYVz4XA+qcRtG7llgNW7UARyIqmBNG7zDQhwsCW/a6LTR/r/fb 7slFktfHgI0lOtjwZmYHgMU2tIzKYDo= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-484-fMpO1OkAO82UG2QyzH8qhQ-1; Mon, 02 Oct 2023 14:24:15 -0400 X-MC-Unique: fMpO1OkAO82UG2QyzH8qhQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 65DE83C0DF68 for ; Mon, 2 Oct 2023 18:24:15 +0000 (UTC) Received: from [10.39.192.119] (unknown [10.39.192.119]) by smtp.corp.redhat.com (Postfix) with ESMTPS id BF49C40C2070; Mon, 2 Oct 2023 18:24:13 +0000 (UTC) Message-ID: <05c80aca-8134-49b8-286b-853a02359ed6@redhat.com> Date: Mon, 2 Oct 2023 20:24:11 +0200 MIME-Version: 1.0 Subject: Re: [PATCH v2 4/5] ramfb: make migration conditional To: Alex Williamson , =?UTF-8?Q?C=c3=a9dric_Le_Goater?= Cc: marcandre.lureau@redhat.com, qemu-devel@nongnu.org, kraxel@redhat.com, Paolo Bonzini References: <20231002111154.1002655-1-marcandre.lureau@redhat.com> <20231002111154.1002655-5-marcandre.lureau@redhat.com> <20231002084134.22fee251.alex.williamson@redhat.com> Content-Language: en-US From: Laszlo Ersek In-Reply-To: <20231002084134.22fee251.alex.williamson@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 Received-SPF: pass client-ip=170.10.133.124; envelope-from=lersek@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: 12 X-Spam_score: 1.2 X-Spam_bar: + X-Spam_report: (1.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_SBL_CSS=3.335, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 10/2/23 16:41, Alex Williamson wrote: > On Mon, 2 Oct 2023 15:38:10 +0200 > Cédric Le Goater wrote: > >> On 10/2/23 13:11, marcandre.lureau@redhat.com wrote: >>> From: Marc-André Lureau >>> >>> RAMFB migration was unsupported until now, let's make it conditional. >>> The following patch will prevent machines <= 8.1 to migrate it. >>> >>> Signed-off-by: Marc-André Lureau >> Maybe localize the new 'ramfb_migrate' attribute close to 'enable_ramfb' >> in VFIOPCIDevice. Anyhow, > > Shouldn't this actually be tied to whether the device is migratable > (which for GVT-g - the only ramfb user afaik - it's not)? What does it > mean to have a ramfb-migrate=true property on a device that doesn't > support migration, or false on a device that does support migration. I > don't understand why this is a user controllable property. Thanks, The comments in (which are unfortunately not public :/ ) suggest that ramfb migration was simply forgotten when vGPU migration was implemented. So, "now that vGPU migration is done", this should be added. Comment 8 suggests that the following domain XML snippet
is migratable, but the ramfb device malfunctions on the destination host. There's also a huge QEMU cmdline in comment#0 of the bug; I've not tried to read that. AIUI BTW the property is not for the user to control, it's just a compat knob for versioned machine types. AIUI those are usually implemented with such (user-visible / -tweakable) device properties. Laszlo > > Alex > >>> --- >>> hw/vfio/pci.h | 1 + >>> include/hw/display/ramfb.h | 2 +- >>> hw/display/ramfb-standalone.c | 8 +++++++- >>> hw/display/ramfb.c | 6 ++++-- >>> hw/vfio/display.c | 4 ++-- >>> hw/vfio/pci.c | 1 + >>> stubs/ramfb.c | 2 +- >>> 7 files changed, 17 insertions(+), 7 deletions(-) >>> >>> diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h >>> index 2d836093a8..671cc78912 100644 >>> --- a/hw/vfio/pci.h >>> +++ b/hw/vfio/pci.h >>> @@ -156,6 +156,7 @@ struct VFIOPCIDevice { >>> OnOffAuto display; >>> uint32_t display_xres; >>> uint32_t display_yres; >>> + bool ramfb_migrate; >>> int32_t bootindex; >>> uint32_t igd_gms; >>> OffAutoPCIBAR msix_relo; >>> diff --git a/include/hw/display/ramfb.h b/include/hw/display/ramfb.h >>> index b33a2c467b..40063b62bd 100644 >>> --- a/include/hw/display/ramfb.h >>> +++ b/include/hw/display/ramfb.h >>> @@ -4,7 +4,7 @@ >>> /* ramfb.c */ >>> typedef struct RAMFBState RAMFBState; >>> void ramfb_display_update(QemuConsole *con, RAMFBState *s); >>> -RAMFBState *ramfb_setup(Error **errp); >>> +RAMFBState *ramfb_setup(bool migrate, Error **errp); >>> >>> /* ramfb-standalone.c */ >>> #define TYPE_RAMFB_DEVICE "ramfb" >>> diff --git a/hw/display/ramfb-standalone.c b/hw/display/ramfb-standalone.c >>> index 8c0094397f..6bbd69ccdf 100644 >>> --- a/hw/display/ramfb-standalone.c >>> +++ b/hw/display/ramfb-standalone.c >>> @@ -15,6 +15,7 @@ struct RAMFBStandaloneState { >>> SysBusDevice parent_obj; >>> QemuConsole *con; >>> RAMFBState *state; >>> + bool migrate; >>> }; >>> >>> static void display_update_wrapper(void *dev) >>> @@ -37,9 +38,13 @@ static void ramfb_realizefn(DeviceState *dev, Error **errp) >>> RAMFBStandaloneState *ramfb = RAMFB(dev); >>> >>> ramfb->con = graphic_console_init(dev, 0, &wrapper_ops, dev); >>> - ramfb->state = ramfb_setup(errp); >>> + ramfb->state = ramfb_setup(ramfb->migrate, errp); >>> } >>> >>> +static Property ramfb_properties[] = { >>> + DEFINE_PROP_BOOL("migrate", RAMFBStandaloneState, migrate, true), >>> + DEFINE_PROP_END_OF_LIST(), >>> +}; >>> static void ramfb_class_initfn(ObjectClass *klass, void *data) >>> { >>> DeviceClass *dc = DEVICE_CLASS(klass); >>> @@ -48,6 +53,7 @@ static void ramfb_class_initfn(ObjectClass *klass, void *data) >>> dc->realize = ramfb_realizefn; >>> dc->desc = "ram framebuffer standalone device"; >>> dc->user_creatable = true; >>> + device_class_set_props(dc, ramfb_properties); >>> } >>> >>> static const TypeInfo ramfb_info = { >>> diff --git a/hw/display/ramfb.c b/hw/display/ramfb.c >>> index 4aaaa7d653..73e08d605f 100644 >>> --- a/hw/display/ramfb.c >>> +++ b/hw/display/ramfb.c >>> @@ -135,7 +135,7 @@ static const VMStateDescription vmstate_ramfb = { >>> } >>> }; >>> >>> -RAMFBState *ramfb_setup(Error **errp) >>> +RAMFBState *ramfb_setup(bool migrate, Error **errp) >>> { >>> FWCfgState *fw_cfg = fw_cfg_find(); >>> RAMFBState *s; >>> @@ -147,7 +147,9 @@ RAMFBState *ramfb_setup(Error **errp) >>> >>> s = g_new0(RAMFBState, 1); >>> >>> - vmstate_register(NULL, 0, &vmstate_ramfb, s); >>> + if (migrate) { >>> + vmstate_register(NULL, 0, &vmstate_ramfb, s); >>> + } >>> rom_add_vga("vgabios-ramfb.bin"); >>> fw_cfg_add_file_callback(fw_cfg, "etc/ramfb", >>> NULL, ramfb_fw_cfg_write, s, >>> diff --git a/hw/vfio/display.c b/hw/vfio/display.c >>> index bec864f482..3f6b251ccd 100644 >>> --- a/hw/vfio/display.c >>> +++ b/hw/vfio/display.c >>> @@ -356,7 +356,7 @@ static int vfio_display_dmabuf_init(VFIOPCIDevice *vdev, Error **errp) >>> &vfio_display_dmabuf_ops, >>> vdev); >>> if (vdev->enable_ramfb) { >>> - vdev->dpy->ramfb = ramfb_setup(errp); >>> + vdev->dpy->ramfb = ramfb_setup(vdev->ramfb_migrate, errp); >>> } >>> vfio_display_edid_init(vdev); >>> return 0; >>> @@ -483,7 +483,7 @@ static int vfio_display_region_init(VFIOPCIDevice *vdev, Error **errp) >>> &vfio_display_region_ops, >>> vdev); >>> if (vdev->enable_ramfb) { >>> - vdev->dpy->ramfb = ramfb_setup(errp); >>> + vdev->dpy->ramfb = ramfb_setup(vdev->ramfb_migrate, errp); >>> } >>> return 0; >>> } >>> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c >>> index 3b2ca3c24c..6575b8f32d 100644 >>> --- a/hw/vfio/pci.c >>> +++ b/hw/vfio/pci.c >>> @@ -3484,6 +3484,7 @@ static const TypeInfo vfio_pci_dev_info = { >>> >>> static Property vfio_pci_dev_nohotplug_properties[] = { >>> DEFINE_PROP_BOOL("ramfb", VFIOPCIDevice, enable_ramfb, false), >>> + DEFINE_PROP_BOOL("ramfb-migrate", VFIOPCIDevice, ramfb_migrate, true), >>> DEFINE_PROP_END_OF_LIST(), >>> }; >>> >>> diff --git a/stubs/ramfb.c b/stubs/ramfb.c >>> index 48143f3354..8869a5db09 100644 >>> --- a/stubs/ramfb.c >>> +++ b/stubs/ramfb.c >>> @@ -6,7 +6,7 @@ void ramfb_display_update(QemuConsole *con, RAMFBState *s) >>> { >>> } >>> >>> -RAMFBState *ramfb_setup(Error **errp) >>> +RAMFBState *ramfb_setup(bool migrate, Error **errp) >>> { >>> error_setg(errp, "ramfb support not available"); >>> return NULL; >> >