netdev - [PATCH 6/6] ethernet: stmmac: re-init rx buffers when mac resume back

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 11 Jan 2021 19:35:38 +0800
From:   Joakim Zhang <qiangqing.zhang@....com>
To:     peppe.cavallaro@...com, alexandre.torgue@...com,
        joabreu@...opsys.com, davem@...emloft.net, kuba@...nel.org
Cc:     netdev@...r.kernel.org, linux-imx@....com
Subject: [PATCH 6/6] ethernet: stmmac: re-init rx buffers when mac resume back

During suspend/resume stress test, we found descriptor write back by DMA
could exhibit unusual behavior, e.g.:
	003 [0xc4310030]: 0x0 0x40 0x0 0xb5010040

We can see that desc3 write back is 0xb5010040, it is still ownd by DMA,
so application would not recycle this buffer. It will trigger fatal bus
error when DMA try to use this descriptor again. To fix this issue, we
should re-init all rx buffers when mac resume back.

Signed-off-by: Joakim Zhang <qiangqing.zhang@....com>
---
 .../net/ethernet/stmicro/stmmac/stmmac_main.c | 73 ++++++++++++++++++-
 1 file changed, 72 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index e30529b8f40a..e02d798e605b 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -1328,6 +1328,77 @@ static int stmmac_init_rx_buffers(struct stmmac_priv *priv, struct dma_desc *p,
 	return 0;
 }
 
+/**
+ * stmmac_reinit_rx_buffers - reinit the RX descriptor buffer.
+ * @priv: driver private structure
+ * Description: this function is called to re-allocate a receive buffer, perform
+ * the DMA mapping and init the descriptor.
+ */
+static int stmmac_reinit_rx_buffers(struct stmmac_priv *priv)
+{
+	u32 rx_count = priv->plat->rx_queues_to_use;
+	u32 queue;
+	int i;
+
+	for (queue = 0; queue < rx_count; queue++) {
+		struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
+
+		for (i = 0; i < priv->dma_rx_size; i++) {
+			struct stmmac_rx_buffer *buf = &rx_q->buf_pool[i];
+
+			if (buf->page) {
+				page_pool_recycle_direct(rx_q->page_pool, buf->page);
+				buf->page = NULL;
+			}
+
+			if (priv->sph && buf->sec_page) {
+				page_pool_recycle_direct(rx_q->page_pool, buf->sec_page);
+				buf->sec_page = NULL;
+			}
+		}
+	}
+
+	for (queue = 0; queue < rx_count; queue++) {
+		struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
+
+		for (i = 0; i < priv->dma_rx_size; i++) {
+			struct stmmac_rx_buffer *buf = &rx_q->buf_pool[i];
+			struct dma_desc *p;
+
+			if (priv->extend_desc)
+				p = &((rx_q->dma_erx + i)->basic);
+			else
+				p = rx_q->dma_rx + i;
+
+			if (!buf->page) {
+				buf->page = page_pool_dev_alloc_pages(rx_q->page_pool);
+				if (!buf->page)
+					break;
+
+				buf->addr = page_pool_get_dma_addr(buf->page);
+			}
+
+			if (priv->sph && !buf->sec_page) {
+				buf->sec_page = page_pool_dev_alloc_pages(rx_q->page_pool);
+				if (!buf->sec_page)
+					break;
+
+				buf->sec_addr = page_pool_get_dma_addr(buf->sec_page);
+			}
+
+			stmmac_set_desc_addr(priv, p, buf->addr);
+			if (priv->sph)
+				stmmac_set_desc_sec_addr(priv, p, buf->sec_addr, true);
+			else
+				stmmac_set_desc_sec_addr(priv, p, buf->sec_addr, false);
+			if (priv->dma_buf_sz == BUF_SIZE_16KiB)
+				stmmac_init_desc3(priv, p);
+		}
+	}
+
+	return 0;
+}
+
 /**
  * stmmac_free_rx_buffer - free RX dma buffers
  * @priv: private structure
@@ -5338,7 +5409,7 @@ int stmmac_resume(struct device *dev)
 	mutex_lock(&priv->lock);
 
 	stmmac_reset_queues_param(priv);
-
+	stmmac_reinit_rx_buffers(priv);
 	stmmac_free_tx_skbufs(priv);
 	stmmac_clear_descriptors(priv);
 
-- 
2.17.1