RE: [RFC PATCH v2 2/2] objtool: fix x86 orc generation on big endian cross compiles

[David Laight]

From: Vasily Gorbik
> Sent: 30 September 2020 13:24
> 
> Correct objtool orc generation endianness problems to enable fully
> functional x86 cross compiles on big endian hardware.
> 
...
> +
> +#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : defined(__LITTLE_ENDIAN)
> +
>  struct orc_entry {
>  	s16		sp_offset;
>  	s16		bp_offset;
> @@ -57,6 +67,20 @@ struct orc_entry {
>  	unsigned	end:1;
>  } __packed;
> 
> +#else
> +
> +struct orc_entry {
> +	s16		sp_offset;
> +	s16		bp_offset;
> +	unsigned	bp_reg:4;
> +	unsigned	sp_reg:4;
> +	unsigned	unused:5;
> +	unsigned	end:1;
> +	unsigned	type:2;
> +} __packed;
> +
> +#endif

Shouldn't that be checking BITFIELD_ENDIAN.

I also think that (in the other patch) you can assume
that you don't need to byteswap if __KERNEL__ is defined.

	David

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