Re: [PATCH -next] arm64: mm: Fix unused variable warning in zone_sizes_init

[Will Deacon]

On Tue, Oct 15, 2019 at 03:43:04PM -0700, Nathan Chancellor wrote:
> When building arm64 allnoconfig, CONFIG_ZONE_DMA and CONFIG_ZONE_DMA32
> get disabled so there is a warning about max_dma being unused.
> 
> ../arch/arm64/mm/init.c:215:16: warning: unused variable 'max_dma'
> [-Wunused-variable]
>         unsigned long max_dma = min;
>                       ^
> 1 warning generated.
> 
> Add an ifdef around the variable to fix this.
> 
> Fixes: 1a8e1cef7603 ("arm64: use both ZONE_DMA and ZONE_DMA32")
> Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> ---
>  arch/arm64/mm/init.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> index 44f07fdf7a59..c3d6657b9942 100644
> --- a/arch/arm64/mm/init.c
> +++ b/arch/arm64/mm/init.c
> @@ -212,7 +212,9 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)
>  	struct memblock_region *reg;
>  	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
>  	unsigned long max_dma32 = min;
> +#if defined(CONFIG_ZONE_DMA) || defined(CONFIG_ZONE_DMA)
>  	unsigned long max_dma = min;
> +#endif

This looks bogus to me :/ You're referring to CONFIG_ZONE_DMA twice, and I
can't see how that symbol even exists on arm64.

Will