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Date:   Mon, 14 Jun 2021 09:12:15 -0700
From:   Ben Widawsky <ben.widawsky@intel.com>
To:     Dan Williams <dan.j.williams@intel.com>
Cc:     linux-cxl@vger.kernel.org,
        Alison Schofield <alison.schofield@intel.com>,
        Ira Weiny <ira.weiny@intel.com>,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        Vishal Verma <vishal.l.verma@intel.com>
Subject: Re: [RFC PATCH 2/4] cxl/region: Create attribute structure / verify
Message-ID: <20210614161215.eae4ss7hgwoag27m@intel.com>
References: <20210610185725.897541-1-ben.widawsky@intel.com>
 <20210610185725.897541-3-ben.widawsky@intel.com>
 <CAPcyv4hpxbnvGVQAc15RwGyu1XH8JyiBs8prBG8Rx2wkL3=MpQ@mail.gmail.com>
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On 21-06-11 17:59:15, Dan Williams wrote:
> On Thu, Jun 10, 2021 at 11:57 AM Ben Widawsky <ben.widawsky@intel.com> 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().

Addressed this in the other email...

> 
> > 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.

Hopefully I didn't forget to mention that verify() would be an optional call
from userspace. Perhaps making it debugfs makes more sense?