[PATCH] z3fold: fix sheduling while atomic

From: Vitaly Wool
Date: Thu May 23 2019 - 09:35:42 EST


kmem_cache_alloc() may be called from z3fold_alloc() in atomic
context, so we need to pass correct gfp flags to avoid "scheduling
while atomic" bug.

Signed-off-by: Vitaly Wool <vitaly.vul@xxxxxxxx>
---
mm/z3fold.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/mm/z3fold.c b/mm/z3fold.c
index 99be52c5ca45..985732c8b025 100644
--- a/mm/z3fold.c
+++ b/mm/z3fold.c
@@ -190,10 +190,11 @@ static int size_to_chunks(size_t size)

static void compact_page_work(struct work_struct *w);

-static inline struct z3fold_buddy_slots *alloc_slots(struct z3fold_pool *pool)
+static inline struct z3fold_buddy_slots *alloc_slots(struct z3fold_pool *pool,
+ gfp_t gfp)
{
struct z3fold_buddy_slots *slots = kmem_cache_alloc(pool->c_handle,
- GFP_KERNEL);
+ gfp);

if (slots) {
memset(slots->slot, 0, sizeof(slots->slot));
@@ -295,10 +296,10 @@ 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,
- struct z3fold_pool *pool)
+ struct z3fold_pool *pool, gfp_t gfp)
{
struct z3fold_header *zhdr = page_address(page);
- struct z3fold_buddy_slots *slots = alloc_slots(pool);
+ struct z3fold_buddy_slots *slots = alloc_slots(pool, gfp);

if (!slots)
return NULL;
@@ -912,7 +913,7 @@ static int z3fold_alloc(struct z3fold_pool *pool, size_t size, gfp_t gfp,
if (!page)
return -ENOMEM;

- zhdr = init_z3fold_page(page, pool);
+ zhdr = init_z3fold_page(page, pool, gfp);
if (!zhdr) {
__free_page(page);
return -ENOMEM;
--
2.17.1