mm: cma: WARN if freed memory is still in use

Memory returned to free_contig_range() must have no other references.
Let kernel to complain loudly if page reference count is not equal to 1.

[rientjes@google.com: support sparsemem]
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Marek Szyprowski 2012-12-20 15:05:18 -08:00 committed by Linus Torvalds
parent b66c598401
commit bcc2b02f4c
1 changed files with 9 additions and 2 deletions

View File

@ -5978,8 +5978,15 @@ done:
void free_contig_range(unsigned long pfn, unsigned nr_pages)
{
for (; nr_pages--; ++pfn)
__free_page(pfn_to_page(pfn));
unsigned int count = 0;
for (; nr_pages--; pfn++) {
struct page *page = pfn_to_page(pfn);
count += page_count(page) != 1;
__free_page(page);
}
WARN(count != 0, "%d pages are still in use!\n", count);
}
#endif