Subject: linux-next: build failure after merge of the akpm-current tree

From: Stephen Rothwell <[email-masked]>
Date: Thu, 7 May 2020 22:17:21 +1000

Hi all,

After merging the akpm-current tree, today's linux-next build (arm
collie_defconfig and many others) failed like this:

arch/arm/mm/dma-mapping.c: In function 'dma_cache_maint_page':
arch/arm/mm/dma-mapping.c:892:6: error: implicit declaration of function 'kunmap_high' [-Werror=implicit-function-declaration]
      kunmap_high(page);
      ^
arch/arm/mm/flush.c: In function '__flush_dcache_page':
arch/arm/mm/flush.c:221:6: error: implicit declaration of function 'kunmap_high' [-Werror=implicit-function-declaration]
      kunmap_high(page + i);
      ^

Caused by commit

  6b66ab470b4d ("arch/kunmap: remove duplicate kunmap implementations")

kunmap_high() is now only declared when CONFIG_HIGHMEM is defined.

-- 
Cheers,
Stephen Rothwell