| Message ID | 20250321120222.1456770-2-gshan@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Fix parameter passed to page_mapcount_is_type() | expand |
On 3/21/25 13:02, Gavin Shan wrote: > As the comments of page_mapcount_is_type() indicate, the parameter > passed to the function should be one more than page->_mapcount. > However, page->_mapcount (equivalent to page->page_type) is passed > to the function by commit 4ffca5a96678 ("mm: support only one page_type > per page") page_type_has_type() is replaced by page_mapcount_is_type(), > but the parameter isn't adjusted. > > Fix it by replacing page_mapcount_is_type() with page_type_has_type() > in page_has_type(). Note that the issue doesn't cause any visible impacts > due to the safety gap introduced by PGTY_mapcount_underflow limit. > > Fixes: 4ffca5a96678 ("mm: support only one page_type per page") > Signed-off-by: Gavin Shan <gshan@redhat.com> > Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> > --- > include/linux/page-flags.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h > index 36d283552f80..e1a9f84bd5ab 100644 > --- a/include/linux/page-flags.h > +++ b/include/linux/page-flags.h > @@ -950,7 +950,7 @@ static inline bool page_mapcount_is_type(unsigned int mapcount) > > static inline bool page_has_type(const struct page *page) > { > - return page_mapcount_is_type(data_race(page->page_type)); > + return page_type_has_type(data_race(page->page_type)); > } > > #define FOLIO_TYPE_OPS(lname, fname) \
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 36d283552f80..e1a9f84bd5ab 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -950,7 +950,7 @@ static inline bool page_mapcount_is_type(unsigned int mapcount) static inline bool page_has_type(const struct page *page) { - return page_mapcount_is_type(data_race(page->page_type)); + return page_type_has_type(data_race(page->page_type)); } #define FOLIO_TYPE_OPS(lname, fname) \
As the comments of page_mapcount_is_type() indicate, the parameter passed to the function should be one more than page->_mapcount. However, page->_mapcount (equivalent to page->page_type) is passed to the function by commit 4ffca5a96678 ("mm: support only one page_type per page") page_type_has_type() is replaced by page_mapcount_is_type(), but the parameter isn't adjusted. Fix it by replacing page_mapcount_is_type() with page_type_has_type() in page_has_type(). Note that the issue doesn't cause any visible impacts due to the safety gap introduced by PGTY_mapcount_underflow limit. Fixes: 4ffca5a96678 ("mm: support only one page_type per page") Signed-off-by: Gavin Shan <gshan@redhat.com> Acked-by: David Hildenbrand <david@redhat.com> --- include/linux/page-flags.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)