[U-Boot] [RFC PATCH v3 0/2] env: Make environment loading log more clear

[Sam Protsenko]

On Fri, Jul 20, 2018 at 4:27 PM, Wolfgang Denk <wd at denx.de> wrote:
> Dear Sam,
>
> In message <20180719222843.28316-1-semen.protsenko at linaro.org> you wrote:
>>
>>  1. With no "Failed" message, at some point we *can* end up with no
>>     error messages printed at all
>
> That would mean that we did not check the whole call tree as needed.
> It is not that complicated, or is it?
>

I've checked the error chain for FAT/MMC env load: [1]. As for the
rest of possible sources, frankly I didn't check, as I don't have such
boards at my disposal anyway, and I may not be aware of all sources we
have. That's why I've only corrected the path for loading from FAT,
which I can test and can argue it's working right. I will add the
comment in env_load() saying that error message must be printed from
underlying subsystem, and it should be exactly one error. If we catch
any related issues further, we can check it on the sport. I hope
you're ok with this approach, as fixing all possible error cases for
all possible sources in at once seems to be too complex task. And some
further messages can appear further, if someone would manage to get
such a patch merged. So let's start with clear requirement in
env_load().

[1] https://pastebin.com/q6kgpprb

>>  2. Removing some collateral error messages *may* lead to loss of useful
>>     debug info in other use-cases (env_load() is not only user of those
>>     APIs).
>
> I dislike the "can" and "may" parts here.  If this is done
> thoroughly, we should know exactly that no such damage gets done.
>

Agree. Also, I like Tom's suggestion to move those to debug() instead
of removing.

> As I mentioend before: if we get here, somewhere an error must have
> occurred.  And in the error handling an error message (one) must be
> printed.
>
> Best regards,
>
> Wolfgang Denk
>
> --
> DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
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