From: Thierry Reding <treding@xxxxxxxxxx> [ Upstream commit 4f28bd956e081fc018fe9b41ffa31573f17bfb61 ] The size of individual pages in the page pool in given by an order. The order is the binary logarithm of the number of pages that make up one of the pages in the pool. However, the driver currently passes the number of pages rather than the order, so it ends up wasting quite a bit of memory. Fix this by taking the binary logarithm and passing that in the order field. Fixes: 2af6106ae949 ("net: stmmac: Introducing support for Page Pool") Signed-off-by: Thierry Reding <treding@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1532,13 +1532,15 @@ static int alloc_dma_rx_desc_resources(s for (queue = 0; queue < rx_count; queue++) { struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue]; struct page_pool_params pp_params = { 0 }; + unsigned int num_pages; rx_q->queue_index = queue; rx_q->priv_data = priv; pp_params.flags = PP_FLAG_DMA_MAP; pp_params.pool_size = DMA_RX_SIZE; - pp_params.order = DIV_ROUND_UP(priv->dma_buf_sz, PAGE_SIZE); + num_pages = DIV_ROUND_UP(priv->dma_buf_sz, PAGE_SIZE); + pp_params.order = ilog2(num_pages); pp_params.nid = dev_to_node(priv->device); pp_params.dev = priv->device; pp_params.dma_dir = DMA_FROM_DEVICE;