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Date:   Tue, 31 Oct 2023 10:13:40 -0700
From:   Ira Weiny <ira.weiny@intel.com>
To:     Dan Williams <dan.j.williams@intel.com>,
        Ira Weiny <ira.weiny@intel.com>,
        Jonathan Cameron <jonathan.cameron@huawei.com>,
        Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>
CC:     Yazen Ghannam <yazen.ghannam@amd.com>,
        Davidlohr Bueso <dave@stgolabs.net>,
        Dave Jiang <dave.jiang@intel.com>,
        Alison Schofield <alison.schofield@intel.com>,
        Vishal Verma <vishal.l.verma@intel.com>,
        "Ard Biesheuvel" <ardb@kernel.org>, <linux-efi@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <linux-cxl@vger.kernel.org>,
        Ira Weiny <ira.weiny@intel.com>
Subject: RE: [PATCH RFC v2 3/3] cxl/memdev: Register for and process CPER
 events
Message-ID: <654135c4f3e0_2e75b2949e@iweiny-mobl.notmuch>
References: <20230601-cxl-cper-v2-0-314d9c36ab02@intel.com>
 <20230601-cxl-cper-v2-3-314d9c36ab02@intel.com>
 <653aee8ad2717_780ef29418@dwillia2-xfh.jf.intel.com.notmuch>
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Dan Williams wrote:
> Ira Weiny wrote:
> > If the firmware has configured CXL event support to be firmware first
> > the OS can process those events through CPER records.  Matching memory
> > devices to the CPER records can be done via the serial number which is
> > part of the CPER record header.
> > 
> > Detect firmware first, register a notifier callback for each memdev, and
> > trace events when they match a device registered.
> > 
> > Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> > 
> [..]
> 
> The changes requested in patch2 cover all of the comments I currently
> have on this patch, just one more cleanup below:
> 
> > +#define CXL_EVENT_HDR_FLAGS_REC_SEVERITY GENMASK(1, 0)
> > +int cxl_cper_event_call(struct notifier_block *nb, unsigned long action, void *data)
> > +{
> > +	struct cxl_cper_notifier_data *nd = data;
> > +	struct cxl_event_record_raw record = (struct cxl_event_record_raw) {
> > +		.hdr.id = UUID_INIT(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
> > +	};
> 
> Just do:
> 
> 	struct cxl_event_record_raw record = { 0 };
> 
> ...and the compiler will take care of the rest as initializing any field
> automatically initializes everything else to zero.

Not quite sure what I was thinking.

This works better but I think I can avoid needing this initialization all
together by reworking the structures.  For now I have made the change and
I'll see how it falls out.

Thanks,
Ira