--- /dev/null
+From 07b3975352374c3f5ebb4a42ef0b253fe370542d Mon Sep 17 00:00:00 2001
+From: Aaro Koskinen <aaro.koskinen@nokia.com>
+Date: Wed, 27 Mar 2019 22:35:37 +0200
+Subject: net: stmmac: don't stop NAPI processing when dropping a packet
+
+From: Aaro Koskinen <aaro.koskinen@nokia.com>
+
+commit 07b3975352374c3f5ebb4a42ef0b253fe370542d upstream.
+
+Currently, if we drop a packet, we exit from NAPI loop before the budget
+is consumed. In some situations this will make the RX processing stall
+e.g. when flood pinging the system with oversized packets, as the
+errorneous packets are not dropped efficiently.
+
+If we drop a packet, we should just continue to the next one as long as
+the budget allows.
+
+Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+[acj: backport v4.4 -stable
+-adjust context]
+Signed-off-by: Aviraj CJ <acj@cisco.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 12 ++++++------
+ 1 file changed, 6 insertions(+), 6 deletions(-)
+
+--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
++++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+@@ -2176,8 +2176,7 @@ static inline void stmmac_rx_refill(stru
+ static int stmmac_rx(struct stmmac_priv *priv, int limit)
+ {
+ unsigned int rxsize = priv->dma_rx_size;
+- unsigned int entry = priv->cur_rx % rxsize;
+- unsigned int next_entry;
++ unsigned int next_entry = priv->cur_rx % rxsize;
+ unsigned int count = 0;
+ int coe = priv->hw->rx_csum;
+
+@@ -2189,9 +2188,11 @@ static int stmmac_rx(struct stmmac_priv
+ stmmac_display_ring((void *)priv->dma_rx, rxsize, 0);
+ }
+ while (count < limit) {
+- int status;
++ int status, entry;
+ struct dma_desc *p;
+
++ entry = next_entry;
++
+ if (priv->extend_desc)
+ p = (struct dma_desc *)(priv->dma_erx + entry);
+ else
+@@ -2239,7 +2240,7 @@ static int stmmac_rx(struct stmmac_priv
+ /* check if frame_len fits the preallocated memory */
+ if (frame_len > priv->dma_buf_sz) {
+ priv->dev->stats.rx_length_errors++;
+- break;
++ continue;
+ }
+
+ /* ACS is set; GMAC core strips PAD/FCS for IEEE 802.3
+@@ -2260,7 +2261,7 @@ static int stmmac_rx(struct stmmac_priv
+ pr_err("%s: Inconsistent Rx descriptor chain\n",
+ priv->dev->name);
+ priv->dev->stats.rx_dropped++;
+- break;
++ continue;
+ }
+ prefetch(skb->data - NET_IP_ALIGN);
+ priv->rx_skbuff[entry] = NULL;
+@@ -2291,7 +2292,6 @@ static int stmmac_rx(struct stmmac_priv
+ priv->dev->stats.rx_packets++;
+ priv->dev->stats.rx_bytes += frame_len;
+ }
+- entry = next_entry;
+ }
+
+ stmmac_rx_refill(priv);
--- /dev/null
+From 583e6361414903c5206258a30e5bd88cb03c0254 Mon Sep 17 00:00:00 2001
+From: Aaro Koskinen <aaro.koskinen@nokia.com>
+Date: Wed, 27 Mar 2019 22:35:35 +0200
+Subject: net: stmmac: use correct DMA buffer size in the RX descriptor
+
+From: Aaro Koskinen <aaro.koskinen@nokia.com>
+
+commit 583e6361414903c5206258a30e5bd88cb03c0254 upstream.
+
+We always program the maximum DMA buffer size into the receive descriptor,
+although the allocated size may be less. E.g. with the default MTU size
+we allocate only 1536 bytes. If somebody sends us a bigger frame, then
+memory may get corrupted.
+
+Fix by using exact buffer sizes.
+
+Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+[acj: backport to v4.4 -stable :
+- Modified patch since v4.4 driver has no support for Big endian
+- Skipped the section modifying non-existent functions in dwmac4_descs.c and
+dwxgmac2_descs.c ]
+Signed-off-by: Aviraj CJ <acj@cisco.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/net/ethernet/stmicro/stmmac/common.h | 2 +-
+ drivers/net/ethernet/stmicro/stmmac/descs_com.h | 14 ++++++++++----
+ drivers/net/ethernet/stmicro/stmmac/enh_desc.c | 10 +++++++---
+ drivers/net/ethernet/stmicro/stmmac/norm_desc.c | 10 +++++++---
+ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++--
+ 5 files changed, 27 insertions(+), 13 deletions(-)
+
+--- a/drivers/net/ethernet/stmicro/stmmac/common.h
++++ b/drivers/net/ethernet/stmicro/stmmac/common.h
+@@ -301,7 +301,7 @@ struct dma_features {
+ struct stmmac_desc_ops {
+ /* DMA RX descriptor ring initialization */
+ void (*init_rx_desc) (struct dma_desc *p, int disable_rx_ic, int mode,
+- int end);
++ int end, int bfsize);
+ /* DMA TX descriptor ring initialization */
+ void (*init_tx_desc) (struct dma_desc *p, int mode, int end);
+
+--- a/drivers/net/ethernet/stmicro/stmmac/descs_com.h
++++ b/drivers/net/ethernet/stmicro/stmmac/descs_com.h
+@@ -33,9 +33,10 @@
+ /* Specific functions used for Ring mode */
+
+ /* Enhanced descriptors */
+-static inline void ehn_desc_rx_set_on_ring(struct dma_desc *p, int end)
++static inline void ehn_desc_rx_set_on_ring(struct dma_desc *p, int end, int bfsize)
+ {
+- p->des01.erx.buffer2_size = BUF_SIZE_8KiB - 1;
++ if (bfsize == BUF_SIZE_16KiB)
++ p->des01.erx.buffer2_size = BUF_SIZE_8KiB - 1;
+ if (end)
+ p->des01.erx.end_ring = 1;
+ }
+@@ -61,9 +62,14 @@ static inline void enh_set_tx_desc_len_o
+ }
+
+ /* Normal descriptors */
+-static inline void ndesc_rx_set_on_ring(struct dma_desc *p, int end)
++static inline void ndesc_rx_set_on_ring(struct dma_desc *p, int end, int bfsize)
+ {
+- p->des01.rx.buffer2_size = BUF_SIZE_2KiB - 1;
++ int size;
++
++ if (bfsize >= BUF_SIZE_2KiB) {
++ size = min(bfsize - BUF_SIZE_2KiB + 1, BUF_SIZE_2KiB - 1);
++ p->des01.rx.buffer2_size = size;
++ }
+ if (end)
+ p->des01.rx.end_ring = 1;
+ }
+--- a/drivers/net/ethernet/stmicro/stmmac/enh_desc.c
++++ b/drivers/net/ethernet/stmicro/stmmac/enh_desc.c
+@@ -238,16 +238,20 @@ static int enh_desc_get_rx_status(void *
+ }
+
+ static void enh_desc_init_rx_desc(struct dma_desc *p, int disable_rx_ic,
+- int mode, int end)
++ int mode, int end, int bfsize)
+ {
++ int bfsize1;
++
+ p->des01.all_flags = 0;
+ p->des01.erx.own = 1;
+- p->des01.erx.buffer1_size = BUF_SIZE_8KiB - 1;
++
++ bfsize1 = min(bfsize, BUF_SIZE_8KiB - 1);
++ p->des01.erx.buffer1_size = bfsize1;
+
+ if (mode == STMMAC_CHAIN_MODE)
+ ehn_desc_rx_set_on_chain(p, end);
+ else
+- ehn_desc_rx_set_on_ring(p, end);
++ ehn_desc_rx_set_on_ring(p, end, bfsize);
+
+ if (disable_rx_ic)
+ p->des01.erx.disable_ic = 1;
+--- a/drivers/net/ethernet/stmicro/stmmac/norm_desc.c
++++ b/drivers/net/ethernet/stmicro/stmmac/norm_desc.c
+@@ -121,16 +121,20 @@ static int ndesc_get_rx_status(void *dat
+ }
+
+ static void ndesc_init_rx_desc(struct dma_desc *p, int disable_rx_ic, int mode,
+- int end)
++ int end, int bfsize)
+ {
++ int bfsize1;
++
+ p->des01.all_flags = 0;
+ p->des01.rx.own = 1;
+- p->des01.rx.buffer1_size = BUF_SIZE_2KiB - 1;
++
++ bfsize1 = min(bfsize, (BUF_SIZE_2KiB - 1));
++ p->des01.rx.buffer1_size = bfsize1;
+
+ if (mode == STMMAC_CHAIN_MODE)
+ ndesc_rx_set_on_chain(p, end);
+ else
+- ndesc_rx_set_on_ring(p, end);
++ ndesc_rx_set_on_ring(p, end, bfsize);
+
+ if (disable_rx_ic)
+ p->des01.rx.disable_ic = 1;
+--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
++++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+@@ -964,11 +964,11 @@ static void stmmac_clear_descriptors(str
+ if (priv->extend_desc)
+ priv->hw->desc->init_rx_desc(&priv->dma_erx[i].basic,
+ priv->use_riwt, priv->mode,
+- (i == rxsize - 1));
++ (i == rxsize - 1), priv->dma_buf_sz);
+ else
+ priv->hw->desc->init_rx_desc(&priv->dma_rx[i],
+ priv->use_riwt, priv->mode,
+- (i == rxsize - 1));
++ (i == rxsize - 1), priv->dma_buf_sz);
+ for (i = 0; i < txsize; i++)
+ if (priv->extend_desc)
+ priv->hw->desc->init_tx_desc(&priv->dma_etx[i].basic,
projects / thirdparty / kernel / stable-queue.git / commitdiff
