Haren Myneni <ha...@linux.vnet.ibm.com> writes:
>
> NX can set 3rd bit in CR register for XER[SO] (Summation overflow)
> which is not used for paste return value. So. mask this bit to get
> proper return status.
This sounds like a bug fix, but I can't tell from the change log.
What happens if we don't merge this patch? Is it bad?
Should I add:
Fixes: 2392c8c8c045 ("powerpc/powernv/vas: Define copy/paste interfaces")
Cc: sta...@vger.kernel.org # v4.14+
cheers
> diff --git a/arch/powerpc/platforms/powernv/copy-paste.h
> b/arch/powerpc/platforms/powernv/copy-paste.h
> index c9a5036..82392e3 100644
> --- a/arch/powerpc/platforms/powernv/copy-paste.h
> +++ b/arch/powerpc/platforms/powernv/copy-paste.h
> @@ -9,7 +9,8 @@
> #include <asm/ppc-opcode.h>
>
> #define CR0_SHIFT 28
> -#define CR0_MASK 0xF
> +#define CR0_MASK 0xE /* 3rd bit undefined or set for XER[SO] */
> +
> /*
> * Copy/paste instructions:
> *
