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Subject: Re: [SPECIFICATION RFC] The firmware and bootloader log specification
To:     Daniel Kiper <daniel.kiper@oracle.com>, coreboot@coreboot.org,
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References: <20201113235242.k6fzlwmwm2xqhqsi@tomti.i.net-space.pl>
From:   Randy Dunlap <rdunlap@infradead.org>
Message-ID: <ef83facc-b08d-a43d-aff1-e0492ab38064@infradead.org>
Date:   Fri, 13 Nov 2020 19:14:44 -0800
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On 11/13/20 3:52 PM, Daniel Kiper wrote:
> Hey,
> 
> 
> Here is the description (pseudocode) of the structures which will be
> used to store the log data.
> 
> Anyway, I am aware that this is not specification per se.


Yes, you have caveats here. I'm sure that you either already know
or would learn soon enough that struct struct bf_log has some
padding added to it (for alignment) unless it is packed.
Or you could rearrange the order of some of its fields
and save 8 bytes per struct on x86_64.


>   struct bf_log
>   {
>     uint32_t   version;
>     char       producer[64];
>     uint64_t   flags;
>     uint64_t   next_bf_log_addr;
>     uint32_t   next_msg_off;
>     bf_log_msg msgs[];
>   }
> 
>   struct bf_log_msg
>   {
>     uint32_t size;
>     uint64_t ts_nsec;
>     uint32_t level;
>     uint32_t facility;
>     uint32_t msg_off;
>     char     strings[];
>   }


cheers.
-- 
~Randy