[PATCH] powerpc/uaccess: Don't use "m<>" constraint

[Segher Boessenkool]

On Thu, May 07, 2020 at 10:33:24PM +1000, Michael Ellerman wrote:
> The "m<>" constraint breaks compilation with GCC 4.6.x era compilers.
> 
> The use of the constraint allows the compiler to use update-form
> instructions, however in practice current compilers never generate
> those forms for any of the current uses of __put_user_asm_goto().
> 
> We anticipate that GCC 4.6 will be declared unsupported for building
> the kernel in the not too distant future. So for now just switch to
> the "m" constraint.
> 
> Fixes: 334710b1496a ("powerpc/uaccess: Implement unsafe_put_user() using 'asm goto'")
> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>

Acked-by: Segher Boessenkool <segher at kernel.crashing.org>

Thanks!  So much trouble for what looked like such a simple change, all
those years ago :-(


Segher