Commit bf74a370 authored by Magnus Karlsson's avatar Magnus Karlsson Committed by Alexei Starovoitov
Browse files

xsk: Fix refcount warning in xp_dma_map 



Fix a potential refcount warning that a zero value is increased to one
in xp_dma_map, by initializing the refcount to one to start with,
instead of zero plus a refcount_inc().

Fixes: 921b6869 ("xsk: Enable sharing of dma mappings")
Signed-off-by: default avatarMagnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/1600095036-23868-1-git-send-email-magnus.karlsson@gmail.com
parent 74e00676

net/xdp/xsk_buff_pool.c

+2 −2
Original line number Diff line number Diff line
@@ -296,7 +296,7 @@ static struct xsk_dma_map *xp_create_dma_map(struct device *dev, struct net_devi 
	dma_map->dev = dev;

	dma_map->dma_need_sync = false;

	dma_map->dma_pages_cnt = nr_pages;

	refcount_set(&dma_map->users, 0);

	refcount_set(&dma_map->users, 1);

	list_add(&dma_map->list, &umem->xsk_dma_list);

	return dma_map;

}
@@ -369,7 +369,6 @@ static int xp_init_dma_info(struct xsk_buff_pool *pool, struct xsk_dma_map *dma_ 
	pool->dev = dma_map->dev;

	pool->dma_pages_cnt = dma_map->dma_pages_cnt;

	pool->dma_need_sync = dma_map->dma_need_sync;

	refcount_inc(&dma_map->users);

	memcpy(pool->dma_pages, dma_map->dma_pages,

	       pool->dma_pages_cnt * sizeof(*pool->dma_pages));
@@ -390,6 +389,7 @@ int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev, 
		if (err)

			return err;



		refcount_inc(&dma_map->users);

		return 0;

	}