Re: [PATCH] MIPS: Display CPU byteorder in /proc/cpuinfo

[David Daney <ddaney.cavm@gmail.com>]

On 01/21/2015 05:49 AM, Ralf Baechle wrote:
> On Wed, Jan 21, 2015 at 10:22:30AM +0000, Markos Chandras wrote:
>
>>>>> What would use this?  Or in other words, why is this needed?
>>>>
>>>> It was a patch I started including years ago in Gentoo's mips-sources, and just
>>>> never thought much about.  I know it was submitted several times in the past,
>>>> but I can't recall what, if any objection was ever made.  No harm in sending it
>>>> in again...
>>>
>>> Clarification, submitted several times in the past by others.  I think I sent
>>> it in once prior, but never got review or feedback.
>>>
>> I believe this patch is mostly useful for cores that can boot in both LE
>> and BE so being able to tell the byteorder from cpuinfo can be helpful
>> at times. Having readelf and other tools in your userland may not always
>> be the case, but you surely have "cat" :)
>>
>> So that patch looks good to me but i think the #ifdefs can be avoided.
>> Can we use
>>
>> if (config_enabled(CONFIG_CPU_BIG_ENDIAN) {
>> } else {
>> }
>>
>> stuff instead?
>
> Exactly the code Joshua is submitting is what has been there until commit
> 874124ebb630 (Merge with Linux 2.4.15.) in 2001.  One reason to remove it
> was that I had a prototype of a kernel supporting the execution of
> application of native and the other byte order working and the field in
> /proc/cpuinfo was plain lying in that case.  Not a terribly relevant
> reason in retrospective but I'm wondering if just in case we should
> rename the field to kernel_byteorder?
>

This is kind of my reason for questioning adding this thing in the first 
place.

Any user of the data probably wouldn't be ready for the case you 
mention.  *And* the data is available from other sources.


>    Ralf
>