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Date:   Mon, 27 Jun 2022 14:15:17 -0700
From:   Darren Hart <darren@os.amperecomputing.com>
To:     Tony Luck <tony.luck@intel.com>
Cc:     "Rafael J. Wysocki" <rafael@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux ACPI <linux-acpi@vger.kernel.org>,
        Len Brown <lenb@kernel.org>, James Morse <james.morse@arm.com>,
        Borislav Petkov <bp@alien8.de>,
        Doug Rady <dcrady@os.amperecomputing.com>
Subject: Re: [PATCH] ACPI/APEI: Better fix to avoid spamming the console with
 old error logs
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References: <YqpX9npa/wR7mafR@agluck-desk3.sc.intel.com>
 <20220622170906.33759-1-tony.luck@intel.com>
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On Wed, Jun 22, 2022 at 10:09:06AM -0700, Tony Luck wrote:
> The fix in commit 3f8dec116210 ("ACPI/APEI: Limit printable size of BERT
> table data") does not work as intended on systems where the BIOS has a
> fixed size block of memory for the BERT table, relying on s/w to quit
> when it finds a record with estatus->block_status == 0. On these systems
> all errors are suppressed because the check:
> 
> 	if (region_len < ACPI_BERT_PRINT_MAX_LEN)
> 
> always fails.
> 
> New scheme skips individual CPER records that are too large, and also
> limits the total number of records that will be printed to 5.

Apologies for the delay.

This seems like a reasonable approach. Working to confirm new behavior on Ampere
Altra systems (specifically how region_len and estatus_len are related).

-- 
Darren Hart
Ampere Computing / OS and Kernel