Re: [PATCH] mm/damon/vaddr: Include 'highmem.h' to fix a build failure

[Randy Dunlap <rdunlap@infradead.org>]

On 10/14/21 4:08 AM, SeongJae Park wrote:
> Commit 0ff28922686c ("mm/damon/vaddr: separate commonly usable
> functions") in -mm tree[1] moves include of 'highmem.h' from 'vaddr.c'
> to 'prmtv-common.c', though the code for the header is still in
> 'vaddr.c'.  As a result, build with 'CONFIG_HIGHPTE' fails as below:
> 
>      In file included from ../include/linux/mm.h:33:0,
>                        from ../include/linux/kallsyms.h:13,
>                        from ../include/linux/bpf.h:20,
>                        from ../include/linux/bpf-cgroup.h:5,
>                        from ../include/linux/cgroup-defs.h:22,
>                        from ../include/linux/cgroup.h:28,
>                        from ../include/linux/hugetlb.h:9,
>                        from ../mm/damon/vaddr.c:11:
>      ../mm/damon/vaddr.c: In function ‘damon_mkold_pmd_entry’:
>      ../include/linux/pgtable.h:97:12: error: implicit declaration of function ‘kmap_atomic’; did you mean ‘mcopy_atomic’? [-Werror=implicit-function-declaration]
>         ((pte_t *)kmap_atomic(pmd_page(*(dir))) +  \
>                   ^
>      ../include/linux/mm.h:2376:17: note: in expansion of macro ‘pte_offset_map’
>         pte_t *__pte = pte_offset_map(pmd, address); \
>                        ^~~~~~~~~~~~~~
>      ../mm/damon/vaddr.c:387:8: note: in expansion of macro ‘pte_offset_map_lock’
>         pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
>               ^~~~~~~~~~~~~~~~~~~
>      ../include/linux/pgtable.h:99:24: error: implicit declaration of function ‘kunmap_atomic’; did you mean ‘in_atomic’? [-Werror=implicit-function-declaration]
>        #define pte_unmap(pte) kunmap_atomic((pte))
>                               ^
>      ../include/linux/mm.h:2384:2: note: in expansion of macro ‘pte_unmap’
>         pte_unmap(pte);     \
>         ^~~~~~~~~
>      ../mm/damon/vaddr.c:392:2: note: in expansion of macro ‘pte_unmap_unlock’
>         pte_unmap_unlock(pte, ptl);
>         ^~~~~~~~~~~~~~~~
> 
> This commit fixes the issue by moving the include back to 'vaddr.c'.
> 
> [1] https://github.com/hnaz/linux-mm/commit/0ff28922686c
> 
> Reported-by: Randy Dunlap <rdunlap@infradead.org>
> Signed-off-by: SeongJae Park <sj@kernel.org>

Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested

Thanks.

> ---
>   mm/damon/prmtv-common.c | 1 -
>   mm/damon/vaddr.c        | 1 +
>   2 files changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/damon/prmtv-common.c b/mm/damon/prmtv-common.c
> index 1768cbe1b9ff..7e62ee54fb54 100644
> --- a/mm/damon/prmtv-common.c
> +++ b/mm/damon/prmtv-common.c
> @@ -5,7 +5,6 @@
>    * Author: SeongJae Park <sj@kernel.org>
>    */
>   
> -#include <linux/highmem.h>
>   #include <linux/mmu_notifier.h>
>   #include <linux/page_idle.h>
>   #include <linux/pagemap.h>
> diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c
> index ce7e36ca1bff..758501b8d97d 100644
> --- a/mm/damon/vaddr.c
> +++ b/mm/damon/vaddr.c
> @@ -8,6 +8,7 @@
>   #define pr_fmt(fmt) "damon-va: " fmt
>   
>   #include <asm-generic/mman-common.h>
> +#include <linux/highmem.h>
>   #include <linux/hugetlb.h>
>   #include <linux/mmu_notifier.h>
>   #include <linux/page_idle.h>
> 


-- 
~Randy