Commit b6cb4541 authored by Baruch Siach's avatar Baruch Siach Committed by Jakub Kicinski
Browse files

net: stmmac: avoid rx queue overrun 



dma_rx_size can be set as low as 64. Rx budget might be higher than
that. Make sure to not overrun allocated rx buffers when budget is
larger.

Leave one descriptor unused to avoid wrap around of 'dirty_rx' vs
'cur_rx'.

Signed-off-by: default avatarBaruch Siach <baruch@tkos.co.il>
Reviewed-by: default avatarSerge Semin <fancer.lancer@gmail.com>
Fixes: 47dd7a54 ("net: add support for STMicroelectronics Ethernet controllers.")
Link: https://lore.kernel.org/r/d95413e44c97d4692e72cec13a75f894abeb6998.1699897370.git.baruch@tkos.co.il


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent fa02de9e

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

+1 −0
Original line number Diff line number Diff line
@@ -5293,6 +5293,7 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) 


	dma_dir = page_pool_get_dma_dir(rx_q->page_pool);

	buf_sz = DIV_ROUND_UP(priv->dma_conf.dma_buf_sz, PAGE_SIZE) * PAGE_SIZE;

	limit = min(priv->dma_conf.dma_rx_size - 1, (unsigned int)limit);



	if (netif_msg_rx_status(priv)) {

		void *rx_head;