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From: "Luck, Tony" <tony.luck@intel.com>
To: "Weiny, Ira" <ira.weiny@intel.com>
CC: "Jiang, Dave" <dave.jiang@intel.com>, "Williams, Dan J"
	<dan.j.williams@intel.com>, Jonathan Cameron <jonathan.cameron@huawei.com>,
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 Ghannam" <yazen.ghannam@amd.com>, Davidlohr Bueso <dave@stgolabs.net>,
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	<rafael@kernel.org>, Borislav Petkov <bp@alien8.de>
Subject: RE: [PATCH v4 1/2] acpi/ghes: Process CXL Component Events
Thread-Topic: [PATCH v4 1/2] acpi/ghes: Process CXL Component Events
Thread-Index: AQHamFPEcj60tQNEyEGE6JP2gc0nSbGBLgDfgAAKrIA=
Date: Tue, 30 Apr 2024 19:33:50 +0000
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References: <20240426-cxl-cper3-v4-0-58076cce1624@intel.com>
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>> What's the lifetime of that record?
>>
>
> The lifetime is contained to the cxl_cper_post_envent() which does not
> block.  The kfifo_put() copies the data to a cxl specific record to be
> used by the CXL thread for processing.
>
>>
>> Can it be re-used/overwritten
>> before that other kernel thread gets around to looking at it?
>
> Yes because the CXL kernel thread has its own copy in the kfifo.

Ira,

Tracking down the call chain, doubly safe. You first copy that record to
a local variable in cxl_cper_post_event() and then kfifo_put() will copy
that copy into another place for processing.

That was my only concern.

Reviewed-by: Tony Luck <tony.luck@intel.com>

-Tony