Re: [PATCH] powerpc: Make set_endian() return EINVAL when not supporting little endian

Le 26/08/2021 à 05:41, Michael Ellerman a écrit :

Christophe Leroy [off-list ref] writes:

quoted

There is no point in modifying MSR_LE bit on CPUs not supporting
little endian.

Isn't that an ABI break?

Or an ABI fix ? I don't know.

My first thought was that all other 32 bits architectures were returning -EINVAL, but looking at the 
man page of prctl, it is explicit that this is powerpc only.

set_endian(PR_ENDIAN_BIG) should work on a big endian CPU, even if it
does nothing useful.

Fair enough. But shouldn't in that case get_endian() return PR_ENDIAN_BIG instead of returning EINVAL ?

We can do one or the other, but I think it should at least be consistant between them, shouldn't it ?

Christophe