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Date:   Mon, 27 Nov 2023 12:48:00 -0800
From:   Ira Weiny <ira.weiny@intel.com>
To:     Dave Jiang <dave.jiang@intel.com>, Ira Weiny <ira.weiny@intel.com>,
        Jonathan Cameron <jonathan.cameron@huawei.com>,
        Fan Ni <nifan.cxl@gmail.com>
CC:     <linux-cxl@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/2] cxl/cdat: Fix header sum value in CDAT checksum
Message-ID: <6565008062aa8_5ec232942e@iweiny-mobl.notmuch>
References: <20231117-fix-cdat-cs-v1-0-ffc2b116ca6c@intel.com>
 <20231117-fix-cdat-cs-v1-2-ffc2b116ca6c@intel.com>
 <962fa507-b9f5-4646-8090-cf63f737e84f@intel.com>
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Dave Jiang wrote:
> 

[snip]

> > diff --git a/hw/cxl/cxl-cdat.c b/hw/cxl/cxl-cdat.c
> > index 24829cf2428d..d93e2e4e64f2 100644
> > --- a/hw/cxl/cxl-cdat.c
> > +++ b/hw/cxl/cxl-cdat.c
> > @@ -95,8 +95,15 @@ static void ct3_build_cdat(CDATObject *cdat, Error **errp)
> >      /* For now, no runtime updates */
> >      cdat_header->sequence = 0;
> >      cdat_header->length += sizeof(CDATTableHeader);
> > -    sum += cdat_header->revision + cdat_header->sequence +
> > -        cdat_header->length;
> > +
> > +    do {
> > +        uint8_t *buf = (uint8_t *)cdat_header;
> > +
> > +        for (i = 0; i < sizeof(*cdat_header); i++) {
> > +            sum += buf[i];
> > +        }
> > +    } while (0);
> 
> Why the empty do/while loop?

Because I used the loop for debugging and forgot to clean up after it was
tested.

I'll send a v2,
Ira