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=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 47B04C48BE6 for ; Sat, 12 Jun 2021 00:59:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1E19961374 for ; Sat, 12 Jun 2021 00:59:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230060AbhFLBB0 (ORCPT ); Fri, 11 Jun 2021 21:01:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51890 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229942AbhFLBB0 (ORCPT ); Fri, 11 Jun 2021 21:01:26 -0400 Received: from mail-pj1-x1035.google.com (mail-pj1-x1035.google.com [IPv6:2607:f8b0:4864:20::1035]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C1E6FC061574 for ; Fri, 11 Jun 2021 17:59:26 -0700 (PDT) Received: by mail-pj1-x1035.google.com with SMTP id 22-20020a17090a0c16b0290164a5354ad0so6795952pjs.2 for ; Fri, 11 Jun 2021 17:59:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=alKWtRf3ItBX1cFlUtmADgfZ9EVycRgYerLOrkJRXx0=; b=Htuos/iB//vMWzgZYbDBBCRU0c4kW6QOoC2RL4Yla2GuQInvtS47oVxFOJuef0Gjuz fu+IY3smWb5wOkrcZoT0taRnEQLokCHYgjQo+7j0PH0WZ2mNFACHTVe9d5F3d+327zJH Ir74uPmJTVGmf6p+FaFEGAr04l30TLizurAY3paQK4TMU+RhG8yB8buWrCODz/37Ltve g73tE7IOb3YJVjvqN9fsPu8UhKgI2ySnTKlflU/GoO581v8QNbU6qw1PVC3xGeRavP49 UrqyYmpaJw/a/PGF9+9OkQYh5cqsJjavwXKB3qn1KtqY4MeG0S/08kGd1fYV/KwPY3SR k1nA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=alKWtRf3ItBX1cFlUtmADgfZ9EVycRgYerLOrkJRXx0=; b=ecdiNIhQ3UDMbcg9hZG654NgLqF55k+KQtoDGHfFUGj2XqAGe6zrLAN78ZHlzuYPlR nxOGEAVvVegMJUOhzRDTVrIXyh8dWyUAK8m8EHkO4/vxY752O7YaYgkgMHpzNGHtmST3 QWf6JMbjQ9LhAuwHFRhdEI1tgRudBb9WfCZ/aL/XQUJobi5TULHid5cSLtNLWtfpJC+t bznqVj05EPdSKnq35MJHrx1gkcq+WF2Ik3Sg0EorfpZOnczcFFchavoGjogD95sXGncA P5VVYFaXHFgwYqEQCRmJgQjPej8I/fE8mMQmAYHVQ1gMP9ymZJ7DTZi2FdQSL1JrlTR4 ffTw== X-Gm-Message-State: AOAM530/+oMC1zw4xJXuQOrkMstnahHYM52LGbmzNmuOjOODeBscq/RU ex253KIpZb7IfUXYKUkk5Aie3jzgtmptK5j2YM0A1Q== X-Google-Smtp-Source: ABdhPJwntfX9HK0rNpSLv0FA2PIDOfraJdWNEzPME87aHlsI1YigoMHkBY9zfWIZ4zkZlZTrMVgCLVKEjIQ3uwuqYpA= X-Received: by 2002:a17:90a:fc88:: with SMTP id ci8mr11850938pjb.13.1623459566104; Fri, 11 Jun 2021 17:59:26 -0700 (PDT) MIME-Version: 1.0 References: <20210610185725.897541-1-ben.widawsky@intel.com> <20210610185725.897541-3-ben.widawsky@intel.com> In-Reply-To: <20210610185725.897541-3-ben.widawsky@intel.com> From: Dan Williams Date: Fri, 11 Jun 2021 17:59:15 -0700 Message-ID: Subject: Re: [RFC PATCH 2/4] cxl/region: Create attribute structure / verify To: Ben Widawsky Cc: linux-cxl@vger.kernel.org, Alison Schofield , Ira Weiny , Jonathan Cameron , Vishal Verma Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org On Thu, Jun 10, 2021 at 11:57 AM Ben Widawsky wrote: > > Introduce a verification mechanism for a region. Regions have complex > configuration requirements and it is beneficial to provide a way to > verify the constraints are met before trying to bind. Primarily it adds > ABI to inform userspace of more detailed information about what failed > rather than the limited choices of errno at bind time. If you want to give userspace more data about an internal process that's a TRACE_EVENT(). > It's important to point out that a verified region can still fail to > bind, but the first step in binding will be to run the same verification > algorithm. I don't see this point of giving userspace a racy / less accurate answer than the bind result.