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=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 A97B3C433DF for ; Wed, 17 Jun 2020 17:59:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 868FC21789 for ; Wed, 17 Jun 2020 17:59:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="SfbMDjXc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726941AbgFQR7w (ORCPT ); Wed, 17 Jun 2020 13:59:52 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:30727 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726864AbgFQR7w (ORCPT ); Wed, 17 Jun 2020 13:59:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592416790; 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: in-reply-to:in-reply-to:references:references; bh=vOyTAkVRj+O9O8epirNOSrk0N1hiwslmvzq2ZgtwDeo=; b=SfbMDjXcvTNiGfT5VH+ckzpKS84ESt1ZO7ROotWgWw4+LvEkcdbHNQrCdnP9MQIdmnES2k nbNiI25KVQPbAAwkEpwgSDHvikSoTpz2JgOq1/wMW7WGu3Kn+4uBNvbwKvunusd2A0NYoZ eJPOsHqg7wQ5jmVYQwX7UcWziQTHNRY= 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-47-7Z7rg9BhOgyUDiuYdTNuSw-1; Wed, 17 Jun 2020 13:59:48 -0400 X-MC-Unique: 7Z7rg9BhOgyUDiuYdTNuSw-1 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 6C6411800D42; Wed, 17 Jun 2020 17:59:47 +0000 (UTC) Received: from work-vm (ovpn-115-47.ams2.redhat.com [10.36.115.47]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 862B419931; Wed, 17 Jun 2020 17:59:39 +0000 (UTC) Date: Wed, 17 Jun 2020 18:59:36 +0100 From: "Dr. David Alan Gilbert" To: David Hildenbrand Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org, qemu-s390x@nongnu.org, Richard Henderson , Paolo Bonzini , Eduardo Habkost , "Michael S . Tsirkin" Subject: Re: [PATCH v4 18/21] virtio-mem: Migration sanity checks Message-ID: <20200617175936.GL2776@work-vm> References: <20200610115419.51688-1-david@redhat.com> <20200610115419.51688-19-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200610115419.51688-19-david@redhat.com> User-Agent: Mutt/1.14.0 (2020-05-02) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org * David Hildenbrand (david@redhat.com) wrote: > We want to make sure that certain properties don't change during > migration, especially to catch user errors in a nice way. Let's migrate > a temporary structure and validate that the properties didn't change. > > Cc: "Michael S. Tsirkin" > Cc: "Dr. David Alan Gilbert" > Signed-off-by: David Hildenbrand Yep OK, but some comment below Reviewed-by: Dr. David Alan Gilbert > --- > hw/virtio/virtio-mem.c | 69 ++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 69 insertions(+) > > diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c > index 2df33f9125..450b8dc49d 100644 > --- a/hw/virtio/virtio-mem.c > +++ b/hw/virtio/virtio-mem.c > @@ -519,12 +519,81 @@ static int virtio_mem_post_load(void *opaque, int version_id) > return virtio_mem_restore_unplugged(VIRTIO_MEM(opaque)); > } > > +typedef struct VirtIOMEMMigSanityChecks { > + VirtIOMEM *parent; > + uint64_t addr; > + uint64_t region_size; > + uint64_t block_size; > + uint32_t node; > +} VirtIOMEMMigSanityChecks; > + > +static int virtio_mem_mig_sanity_checks_pre_save(void *opaque) > +{ > + VirtIOMEMMigSanityChecks *tmp = opaque; > + VirtIOMEM *vmem = tmp->parent; > + > + tmp->addr = vmem->addr; > + tmp->region_size = memory_region_size(&vmem->memdev->mr); > + tmp->block_size = vmem->block_size; > + tmp->node = vmem->node; > + return 0; > +} > + > +static int virtio_mem_mig_sanity_checks_post_load(void *opaque, int version_id) > +{ > + VirtIOMEMMigSanityChecks *tmp = opaque; > + VirtIOMEM *vmem = tmp->parent; > + const uint64_t new_region_size = memory_region_size(&vmem->memdev->mr); > + > + if (tmp->addr != vmem->addr) { > + error_report("Property '%s' changed from 0x%" PRIx64 " to 0x%" PRIx64, > + VIRTIO_MEM_ADDR_PROP, tmp->addr, vmem->addr); > + return -EINVAL; > + } It seems weird that you do 'Property ...' and then the string; although you only do it for 3 out of 4. I was going to ask you to include the device name here, but I'm guessing when it fails the outer migration code will print a 'Failed loading device.....' so at least you know what it is. I would want it to be obvious when I see a 'region size changed' that I knew it was my virtio-mem device that was screwy. Dave > + /* > + * Note: Preparation for resizeable memory regions. The maximum size > + * of the memory region must not change during migration. > + */ > + if (tmp->region_size != new_region_size) { > + error_report("region size changed from 0x%" PRIx64 " to 0x%" PRIx64, > + tmp->region_size, new_region_size); > + return -EINVAL; > + } > + if (tmp->block_size != vmem->block_size) { > + error_report("Property '%s' changed from 0x%" PRIx64 " to 0x%" PRIx64, > + VIRTIO_MEM_BLOCK_SIZE_PROP, tmp->block_size, > + vmem->block_size); > + return -EINVAL; > + } > + if (tmp->node != vmem->node) { > + error_report("Property '%s' changed from %" PRIu32 " to %" PRIu32, > + VIRTIO_MEM_NODE_PROP, tmp->node, vmem->node); > + return -EINVAL; > + } > + return 0; > +} > + > +static const VMStateDescription vmstate_virtio_mem_sanity_checks = { > + .name = "virtio-mem-device/sanity-checks", > + .pre_save = virtio_mem_mig_sanity_checks_pre_save, > + .post_load = virtio_mem_mig_sanity_checks_post_load, > + .fields = (VMStateField[]) { > + VMSTATE_UINT64(addr, VirtIOMEMMigSanityChecks), > + VMSTATE_UINT64(region_size, VirtIOMEMMigSanityChecks), > + VMSTATE_UINT64(block_size, VirtIOMEMMigSanityChecks), > + VMSTATE_UINT32(node, VirtIOMEMMigSanityChecks), > + VMSTATE_END_OF_LIST(), > + }, > +}; > + > static const VMStateDescription vmstate_virtio_mem_device = { > .name = "virtio-mem-device", > .minimum_version_id = 1, > .version_id = 1, > .post_load = virtio_mem_post_load, > .fields = (VMStateField[]) { > + VMSTATE_WITH_TMP(VirtIOMEM, VirtIOMEMMigSanityChecks, > + vmstate_virtio_mem_sanity_checks), > VMSTATE_UINT64(usable_region_size, VirtIOMEM), > VMSTATE_UINT64(size, VirtIOMEM), > VMSTATE_UINT64(requested_size, VirtIOMEM), > -- > 2.26.2 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK