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.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 smtp.lore.kernel.org (Postfix) with ESMTPS id D0C9CCCA48E for ; Mon, 20 Jun 2022 13:06:01 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.352793.579651 (Exim 4.92) (envelope-from ) id 1o3H63-00081L-Ow; Mon, 20 Jun 2022 13:05:39 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 352793.579651; Mon, 20 Jun 2022 13:05:39 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1o3H63-00081E-Ky; Mon, 20 Jun 2022 13:05:39 +0000 Received: by outflank-mailman (input) for mailman id 352793; Mon, 20 Jun 2022 13:05:38 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1o3H61-000818-WB for xen-devel@lists.xenproject.org; Mon, 20 Jun 2022 13:05:38 +0000 Received: from mail-pf1-x434.google.com (mail-pf1-x434.google.com [2607:f8b0:4864:20::434]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id ac9939ff-f099-11ec-b725-ed86ccbb4733; Mon, 20 Jun 2022 15:05:36 +0200 (CEST) Received: by mail-pf1-x434.google.com with SMTP id 128so3171396pfv.12 for ; Mon, 20 Jun 2022 06:05:36 -0700 (PDT) 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: ac9939ff-f099-11ec-b725-ed86ccbb4733 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=5XCq3aw9mDW4vLXTuAFW7Gl3EWmIsDOrQpN5UmWv+fQ=; b=Ca8jZKgHlF+F7xawEGDXXVybMDyfFxCJfWeGe5rrwwK+Rr/qm6/8/qwL3VW1LiU64p AcKMG7+nf5bJxilwQH5VyjMsQwtFSDhsXeVw854pfdR5VsA5RgAuXoqiVWRKT2m1GH9Z ooA3NrC3nbLhKXvBQYIoZD9zkv1QZpWwynStcbJZB20ypW+VqmIUmGdIpS/RuL6udzRw aEXqLR4Tpb7tVMv53/KziPMeSL5AQYuRn4p9+SjUlnaNIRMhrr9qO7JduaUMRtfMKoCt ftixJOFPZn4qTX2u33HAEpvsG3CLLjZFgc33VphqNWdtGIhEN/nbgOxrXHO4ioXDnd4v 3r7g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=5XCq3aw9mDW4vLXTuAFW7Gl3EWmIsDOrQpN5UmWv+fQ=; b=TM3WObaYekd+CrTFIQR8ufpP8Uisxn0hxEaLPrqlM3hwrovPlYwOFeto4tw9B9XnW5 bzrz2btN7idV5rfPtgdj0zfjFB1phCKs4bdNu7+MHjytFh7w1W5+y4dYPFEoG9LDCVUo y2zfuQ3Zg7NI4nMIYntqvx2aRiMD3/EjtaspVS8zQedUA3oIvJIC+ERwi4/0rPGzDmyN H+9VapoY3xhKSnvVcG+Zsd5cul/cKFg4Zlqzyf60HOcgGn5NHnrAUfo+vtWNo/U5SYva khDBkItTFsCc3Acwi6nSGE2Oq1lt2TNBBs6zAR+/Mer+4Vs76d+v/jyyTww4Mtgn6wQa u4Ng== X-Gm-Message-State: AJIora+881xyzcHll63rGGLzqfBz9nCeXZvQD5Vfli/RenYsPxwkvKKR q07LhmsTckA6i2fps/bhdvQMNLIlXylIKIyMttfZkFhlBxI= X-Google-Smtp-Source: AGRyM1uXBgvYNGyYYiJ7P+RDvneEFsseZqD3e1M3vKtyVOasZKg0d1N4yYI9FygAGJMznCH2nFrZKHs8oifoCavKCk8= X-Received: by 2002:a05:6a00:18a9:b0:51b:f63b:6f7c with SMTP id x41-20020a056a0018a900b0051bf63b6f7cmr24394513pfh.49.1655730335169; Mon, 20 Jun 2022 06:05:35 -0700 (PDT) MIME-Version: 1.0 References: <20220609061812.422130-1-jens.wiklander@linaro.org> <20220609061812.422130-3-jens.wiklander@linaro.org> <874k0nhvsq.fsf@epam.com> <20220616223728.GA71444@jade> <94122e8d-224d-2632-27ad-d56d3a24b367@xen.org> In-Reply-To: <94122e8d-224d-2632-27ad-d56d3a24b367@xen.org> From: Jens Wiklander Date: Mon, 20 Jun 2022 15:05:24 +0200 Message-ID: Subject: Re: [PATCH v2 2/2] xen/arm: add FF-A mediator To: Julien Grall Cc: Volodymyr Babchuk , "xen-devel@lists.xenproject.org" , Stefano Stabellini Content-Type: text/plain; charset="UTF-8" Hi Julien, On Fri, Jun 17, 2022 at 10:16 AM Julien Grall wrote: > > Hi Jens, > > On 16/06/2022 23:37, Jens Wiklander wrote: > > On Tue, Jun 14, 2022 at 07:47:18PM +0000, Volodymyr Babchuk wrote: > >> > >> Hello Jens, > >> > >> Sorry for late review, I was busy with internal projects. > >> > >> This is preliminary review. I gave up at scatter-gather operations. Need > >> more time to review them properly. > > > > No problem, thanks for taking the time. > > > >> > >> One thing that bothers me is that Xen is non-preemptive and there are > >> plenty potentially long-running operations. > > > > There's room to deal with that in the FF-A specification. These scatter > > gather operation are quite complicated so I started with the minimum. We > > can as a future optimization address the problem with long running > > operations. > > I would be OK to defer this work. However, I think this should be > written down as Xen community will not be able to security support until > we resolved the known places where a vCPU may hog pCPU longer than > necessary. > > This reminds me that this series doesn't add a support statement for the > new subsystem in SUPPORT.md. AFAICT, this should be tech preview for now. I'll add an entry for this. Thanks, Jens