On 2024/3/27 03:48, Vishal Moola wrote:
On Mon, Mar 04, 2024 at 07:07:20PM +0800, Qi Zheng wrote:
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -206,9 +206,11 @@ static void gmap_free(struct gmap *gmap)
/* Free additional data for a shadow gmap */
if (gmap_is_shadow(gmap)) {
+ struct ptdesc *ptdesc;
+
/* Free all page tables. */
- list_for_each_entry_safe(page, next, &gmap->pt_list, lru)
- page_table_free_pgste(page);
+ list_for_each_entry_safe(ptdesc, next, &gmap->pt_list, pt_list)
+ page_table_free_pgste(ptdesc);
An important note: ptdesc allocation/freeing is different than the
standard alloc_pages()/free_pages() routines architectures are used to.
Are we sure we don't have memory leaks here?
We always allocate and free ptdescs as compound pages; for page table
struct pages, most archictectures do not. s390 has CRST_ALLOC_ORDER
pagetables, meaning if we free anything using the ptdesc api, we better
be sure it was allocated using the ptdesc api as well.
According to the code inspection, all ptdescs added to the pmap->pt_list
are allocated via page_table_alloc_pgste().
Like you, I don't have a s390 to test on, so hopefully some s390 expert
can chime in to let us know if we need a fix for this.
Yes, hope so!
