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=-7.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,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 26EDCC433C1 for ; Tue, 30 Mar 2021 14:31:41 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 AA1B6619BD for ; Tue, 30 Mar 2021 14:31:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AA1B6619BD Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.103554.197521 (Exim 4.92) (envelope-from ) id 1lRFOw-0006RA-Ev; Tue, 30 Mar 2021 14:31:26 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 103554.197521; Tue, 30 Mar 2021 14:31:26 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lRFOw-0006R3-BC; Tue, 30 Mar 2021 14:31:26 +0000 Received: by outflank-mailman (input) for mailman id 103554; Tue, 30 Mar 2021 14:31:24 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lRFOu-0006Qw-Be for xen-devel@lists.xenproject.org; Tue, 30 Mar 2021 14:31:24 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id f3d5c056-aaa4-4211-a677-65f5fcd2a8a9; Tue, 30 Mar 2021 14:31:23 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 98A17B30E; Tue, 30 Mar 2021 14:31:22 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: f3d5c056-aaa4-4211-a677-65f5fcd2a8a9 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1617114682; h=from:from:reply-to: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=ljuuwqZq7fHjy/HZCYWcM8ceacV28zSia7RS3f7Phv8=; b=rvebCMpO/dl/+oO6Hhvu9taIOvI8TMDs22PSbLy+dauzoPGcOJOjARHxyOTQJIXHo1DS7A xvAPHsc039CaYB4XJbSYj9s5Sz1QJLiY1bZ7IbYV7o9rN9tPReMUZompGxwHkl6gyqnZ5h wk3q/f4FiCiDV4cT7YwbTm3bTGZpAgs= Subject: Re: [PATCH 0/2] Introducing hyperlaunch capability design (formerly: DomB mode of dom0less) To: "Daniel P. Smith" Cc: christopher.w.clark@gmail.com, andrew.cooper3@citrix.com, stefano.stabellini@xilinx.com, jgrall@amazon.com, Julien.grall.oss@gmail.com, iwj@xenproject.org, wl@xen.org, george.dunlap@citrix.com, persaur@gmail.com, Bertrand.Marquis@arm.com, roger.pau@citrix.com, luca.fancellu@arm.com, paul@xen.org, adam.schwalm@starlab.io, xen-devel@lists.xenproject.org References: <20210316031814.10311-1-dpsmith@apertussolutions.com> <6314f50f-b4fc-e472-4c9a-3591e168d2c3@apertussolutions.com> From: Jan Beulich Message-ID: Date: Tue, 30 Mar 2021 16:31:21 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.9.0 MIME-Version: 1.0 In-Reply-To: <6314f50f-b4fc-e472-4c9a-3591e168d2c3@apertussolutions.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit On 16.03.2021 04:56, Daniel P. Smith wrote: > To assist in reading, please find attached rendered copies of the design > docs. It should be noted that due to poor rendering by pandoc, we forced > the tables to stay as ASCII tables in the patches whereas the attached > docs have the tables rendered properly by rst2pdf. In section 3.6 I found "As a result, on x86 the hyperlaunch capability does not rely on nor preclude any specific BIOS boot protocol, i.e legacy BIOS boot or UEFI boot. The only requirement is that the boot loader supports the Multiboot2 (MB2) protocol." I'm afraid the two sentences contradict one another, as UEFI on its own doesn't provide MB2 functionality. It is my understanding that you don't require this anyway - what you need is a way to load modules beyond just Dom0 kernel and an initrd. I'm also struggling to see how you mean to associate the (MB2) modules passed to Xen with the individual functions. I.e. I don't see how it will be ensure that the embedded mb-index is in sync with the order or modules actually supplied. As to modules - iirc there are placement restrictions by at least some boot loaders (below 4Gb). If that's correct, do you have any thoughts towards dealing with the limited space available to hold these modules? I've seem systems with lots of memory, but with as little as just 1Gb below the 4Gb boundary. Jan