From: WANG Wenhu <wenhu.wang@xxxxxxxx> Subject: mm: clarify a confusing comment for remap_pfn_range() It really made me scratch my head. Replace the comment with an accurate and consistent description. The parameter pfn actually refers to the page frame number which is right-shifted by PAGE_SHIFT from the physical address. Link: http://lkml.kernel.org/r/20200310073955.43415-1-wenhu.wang@xxxxxxxx Signed-off-by: WANG Wenhu <wenhu.wang@xxxxxxxx> Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memory.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/memory.c~mm-clarify-a-confusing-comment-of-remap_pfn_range +++ a/mm/memory.c @@ -1939,7 +1939,7 @@ static inline int remap_p4d_range(struct * remap_pfn_range - remap kernel memory to userspace * @vma: user vma to map to * @addr: target user address to start at - * @pfn: physical address of kernel memory + * @pfn: page frame number of kernel physical memory address * @size: size of map area * @prot: page protection flags for this mapping * _