Re: [PATCH v9 10/17] ntfs: update attrib operations

Matthew Wilcox
2026-05-03T12:49:19Z

On Fri, Feb 13, 2026 at 05:17:57PM +0900, Namjae Jeon wrote:
> @@ -215,7 +232,7 @@ static int ntfs_decompress(struct page *dest_pages[], int completed_pages[],
> handle_bounds_compressed_page(dp, i_size,
> initialized_size);
> flush_dcache_page(dp);
> - kunmap(dp);
> + kunmap_local(page_address(dp));

This doesn't work. kmap() makes page_address() work, but kmap_local()
doesn't. kmap_local() returns a local mapping of the page, and you have
to kunmap_local() _that_ address. page_address() will continue to
return NULL for highmem pages.

I'll send a patch soon for ntfs_decompress(), but thought I'd flag this
in case there are other places that need to be audited.