Currently there is a leak in init_z3fold_page() -- it allocates handles from kmem cache even for headless pages, but then they are never used and never freed, so eventually kmem cache may get exhausted. This patch provides a fix for that.
Reported-by: Markus Linnala <[email protected]> Signed-off-by: Vitaly Wool <[email protected]> --- mm/z3fold.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/mm/z3fold.c b/mm/z3fold.c index 6397725b5ec6..7dffef2599c3 100644 --- a/mm/z3fold.c +++ b/mm/z3fold.c @@ -301,14 +301,11 @@ static void z3fold_unregister_migration(struct z3fold_pool *pool) } /* Initializes the z3fold header of a newly allocated z3fold page */ -static struct z3fold_header *init_z3fold_page(struct page *page, +static struct z3fold_header *init_z3fold_page(struct page *page, bool headless, struct z3fold_pool *pool, gfp_t gfp) { struct z3fold_header *zhdr = page_address(page); - struct z3fold_buddy_slots *slots = alloc_slots(pool, gfp); - - if (!slots) - return NULL; + struct z3fold_buddy_slots *slots; INIT_LIST_HEAD(&page->lru); clear_bit(PAGE_HEADLESS, &page->private); @@ -316,6 +313,12 @@ static struct z3fold_header *init_z3fold_page(struct page *page, clear_bit(NEEDS_COMPACTING, &page->private); clear_bit(PAGE_STALE, &page->private); clear_bit(PAGE_CLAIMED, &page->private); + if (headless) + return zhdr; + + slots = alloc_slots(pool, gfp); + if (!slots) + return NULL; spin_lock_init(&zhdr->page_lock); kref_init(&zhdr->refcount); @@ -962,7 +965,7 @@ static int z3fold_alloc(struct z3fold_pool *pool, size_t size, gfp_t gfp, if (!page) return -ENOMEM; - zhdr = init_z3fold_page(page, pool, gfp); + zhdr = init_z3fold_page(page, bud == HEADLESS, pool, gfp); if (!zhdr) { __free_page(page); return -ENOMEM; -- 2.17.1
