From 583e6361414903c5206258a30e5bd88cb03c0254 Mon Sep 17 00:00:00 2001 From: Aaro Koskinen Date: Wed, 27 Mar 2019 22:35:35 +0200 Subject: [PATCH 1/6] net: stmmac: use correct DMA buffer size in the RX descriptor 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 Signed-off-by: David S. Miller --- .../net/ethernet/stmicro/stmmac/descs_com.h | 22 ++++++++++++------- .../ethernet/stmicro/stmmac/dwmac4_descs.c | 2 +- .../ethernet/stmicro/stmmac/dwxgmac2_descs.c | 2 +- .../net/ethernet/stmicro/stmmac/enh_desc.c | 10 ++++++--- drivers/net/ethernet/stmicro/stmmac/hwif.h | 2 +- .../net/ethernet/stmicro/stmmac/norm_desc.c | 10 ++++++--- .../net/ethernet/stmicro/stmmac/stmmac_main.c | 6 +++-- 7 files changed, 35 insertions(+), 19 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/descs_com.h b/drivers/net/ethernet/stmicro/stmmac/descs_com.h index 40d6356a7e73..3dfb07a78952 100644 --- a/drivers/net/ethernet/stmicro/stmmac/descs_com.h +++ b/drivers/net/ethernet/stmicro/stmmac/descs_com.h @@ -29,11 +29,13 @@ /* 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->des1 |= cpu_to_le32((BUF_SIZE_8KiB - << ERDES1_BUFFER2_SIZE_SHIFT) - & ERDES1_BUFFER2_SIZE_MASK); + if (bfsize == BUF_SIZE_16KiB) + p->des1 |= cpu_to_le32((BUF_SIZE_8KiB + << ERDES1_BUFFER2_SIZE_SHIFT) + & ERDES1_BUFFER2_SIZE_MASK); if (end) p->des1 |= cpu_to_le32(ERDES1_END_RING); @@ -59,11 +61,15 @@ static inline void enh_set_tx_desc_len_on_ring(struct dma_desc *p, int len) } /* 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->des1 |= cpu_to_le32(((BUF_SIZE_2KiB - 1) - << RDES1_BUFFER2_SIZE_SHIFT) - & RDES1_BUFFER2_SIZE_MASK); + if (bfsize >= BUF_SIZE_2KiB) { + int bfsize2; + + bfsize2 = min(bfsize - BUF_SIZE_2KiB + 1, BUF_SIZE_2KiB - 1); + p->des1 |= cpu_to_le32((bfsize2 << RDES1_BUFFER2_SIZE_SHIFT) + & RDES1_BUFFER2_SIZE_MASK); + } if (end) p->des1 |= cpu_to_le32(RDES1_END_RING); diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c index 7fbb6a4dbf51..e061e9f5fad7 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c @@ -296,7 +296,7 @@ exit: } static void dwmac4_rd_init_rx_desc(struct dma_desc *p, int disable_rx_ic, - int mode, int end) + int mode, int end, int bfsize) { dwmac4_set_rx_owner(p, disable_rx_ic); } diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_descs.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_descs.c index 1d858fdec997..98fa471da7c0 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_descs.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_descs.c @@ -123,7 +123,7 @@ static int dwxgmac2_get_rx_timestamp_status(void *desc, void *next_desc, } static void dwxgmac2_init_rx_desc(struct dma_desc *p, int disable_rx_ic, - int mode, int end) + int mode, int end, int bfsize) { dwxgmac2_set_rx_owner(p, disable_rx_ic); } diff --git a/drivers/net/ethernet/stmicro/stmmac/enh_desc.c b/drivers/net/ethernet/stmicro/stmmac/enh_desc.c index 5ef91a790f9d..e8855e6adb48 100644 --- a/drivers/net/ethernet/stmicro/stmmac/enh_desc.c +++ b/drivers/net/ethernet/stmicro/stmmac/enh_desc.c @@ -259,15 +259,19 @@ static int enh_desc_get_rx_status(void *data, struct stmmac_extra_stats *x, } 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->des0 |= cpu_to_le32(RDES0_OWN); - p->des1 |= cpu_to_le32(BUF_SIZE_8KiB & ERDES1_BUFFER1_SIZE_MASK); + + bfsize1 = min(bfsize, BUF_SIZE_8KiB); + p->des1 |= cpu_to_le32(bfsize1 & ERDES1_BUFFER1_SIZE_MASK); if (mode == STMMAC_CHAIN_MODE) ehn_desc_rx_set_on_chain(p); else - ehn_desc_rx_set_on_ring(p, end); + ehn_desc_rx_set_on_ring(p, end, bfsize); if (disable_rx_ic) p->des1 |= cpu_to_le32(ERDES1_DISABLE_IC); diff --git a/drivers/net/ethernet/stmicro/stmmac/hwif.h b/drivers/net/ethernet/stmicro/stmmac/hwif.h index 92b8944f26e3..5bb00234d961 100644 --- a/drivers/net/ethernet/stmicro/stmmac/hwif.h +++ b/drivers/net/ethernet/stmicro/stmmac/hwif.h @@ -33,7 +33,7 @@ struct dma_extended_desc; 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); /* Invoked by the xmit function to prepare the tx descriptor */ diff --git a/drivers/net/ethernet/stmicro/stmmac/norm_desc.c b/drivers/net/ethernet/stmicro/stmmac/norm_desc.c index de65bb29feba..c55a9815b394 100644 --- a/drivers/net/ethernet/stmicro/stmmac/norm_desc.c +++ b/drivers/net/ethernet/stmicro/stmmac/norm_desc.c @@ -135,15 +135,19 @@ static int ndesc_get_rx_status(void *data, struct stmmac_extra_stats *x, } 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->des0 |= cpu_to_le32(RDES0_OWN); - p->des1 |= cpu_to_le32((BUF_SIZE_2KiB - 1) & RDES1_BUFFER1_SIZE_MASK); + + bfsize1 = min(bfsize, BUF_SIZE_2KiB - 1); + p->des1 |= cpu_to_le32(bfsize & RDES1_BUFFER1_SIZE_MASK); 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->des1 |= cpu_to_le32(RDES1_DISABLE_IC); diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 6a2e1031a62a..4e496cf655f2 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1136,11 +1136,13 @@ static void stmmac_clear_rx_descriptors(struct stmmac_priv *priv, u32 queue) if (priv->extend_desc) stmmac_init_rx_desc(priv, &rx_q->dma_erx[i].basic, priv->use_riwt, priv->mode, - (i == DMA_RX_SIZE - 1)); + (i == DMA_RX_SIZE - 1), + priv->dma_buf_sz); else stmmac_init_rx_desc(priv, &rx_q->dma_rx[i], priv->use_riwt, priv->mode, - (i == DMA_RX_SIZE - 1)); + (i == DMA_RX_SIZE - 1), + priv->dma_buf_sz); } /** From 972c9be784e077bc56472c78243e0326e525b689 Mon Sep 17 00:00:00 2001 From: Aaro Koskinen Date: Wed, 27 Mar 2019 22:35:36 +0200 Subject: [PATCH 2/6] net: stmmac: ratelimit RX error logs Ratelimit RX error logs. Signed-off-by: Aaro Koskinen Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 4e496cf655f2..392d94cede17 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -3433,9 +3433,10 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) * ignored */ if (frame_len > priv->dma_buf_sz) { - netdev_err(priv->dev, - "len %d larger than size (%d)\n", - frame_len, priv->dma_buf_sz); + if (net_ratelimit()) + netdev_err(priv->dev, + "len %d larger than size (%d)\n", + frame_len, priv->dma_buf_sz); priv->dev->stats.rx_length_errors++; break; } @@ -3492,9 +3493,10 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) } else { skb = rx_q->rx_skbuff[entry]; if (unlikely(!skb)) { - netdev_err(priv->dev, - "%s: Inconsistent Rx chain\n", - priv->dev->name); + if (net_ratelimit()) + netdev_err(priv->dev, + "%s: Inconsistent Rx chain\n", + priv->dev->name); priv->dev->stats.rx_dropped++; break; } From 07b3975352374c3f5ebb4a42ef0b253fe370542d Mon Sep 17 00:00:00 2001 From: Aaro Koskinen Date: Wed, 27 Mar 2019 22:35:37 +0200 Subject: [PATCH 3/6] net: stmmac: don't stop NAPI processing when dropping a packet 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 Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 392d94cede17..a26e36dbb5df 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -3354,9 +3354,8 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) { struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue]; struct stmmac_channel *ch = &priv->channel[queue]; - unsigned int entry = rx_q->cur_rx; + unsigned int next_entry = rx_q->cur_rx; int coe = priv->hw->rx_csum; - unsigned int next_entry; unsigned int count = 0; bool xmac; @@ -3374,10 +3373,12 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) stmmac_display_ring(priv, rx_head, DMA_RX_SIZE, true); } while (count < limit) { - int status; + int entry, status; struct dma_desc *p; struct dma_desc *np; + entry = next_entry; + if (priv->extend_desc) p = (struct dma_desc *)(rx_q->dma_erx + entry); else @@ -3438,7 +3439,7 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) "len %d larger than size (%d)\n", 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 @@ -3473,7 +3474,7 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) dev_warn(priv->device, "packet dropped\n"); priv->dev->stats.rx_dropped++; - break; + continue; } dma_sync_single_for_cpu(priv->device, @@ -3498,7 +3499,7 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) "%s: Inconsistent Rx chain\n", priv->dev->name); priv->dev->stats.rx_dropped++; - break; + continue; } prefetch(skb->data - NET_IP_ALIGN); rx_q->rx_skbuff[entry] = NULL; @@ -3533,7 +3534,6 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) priv->dev->stats.rx_packets++; priv->dev->stats.rx_bytes += frame_len; } - entry = next_entry; } stmmac_rx_refill(priv, queue); From 1b746ce8b397e58f9e40ce5c63b7198de6930482 Mon Sep 17 00:00:00 2001 From: Aaro Koskinen Date: Wed, 27 Mar 2019 22:35:38 +0200 Subject: [PATCH 4/6] net: stmmac: don't overwrite discard_frame status If we have error bits set, the discard_frame status will get overwritten by checksum bit checks, which might set the status back to good one. Fix by checking the COE status only if the frame is good. Signed-off-by: Aaro Koskinen Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/enh_desc.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/enh_desc.c b/drivers/net/ethernet/stmicro/stmmac/enh_desc.c index e8855e6adb48..c42ef6c729c0 100644 --- a/drivers/net/ethernet/stmicro/stmmac/enh_desc.c +++ b/drivers/net/ethernet/stmicro/stmmac/enh_desc.c @@ -231,9 +231,10 @@ static int enh_desc_get_rx_status(void *data, struct stmmac_extra_stats *x, * It doesn't match with the information reported into the databook. * At any rate, we need to understand if the CSUM hw computation is ok * and report this info to the upper layers. */ - ret = enh_desc_coe_rdes0(!!(rdes0 & RDES0_IPC_CSUM_ERROR), - !!(rdes0 & RDES0_FRAME_TYPE), - !!(rdes0 & ERDES0_RX_MAC_ADDR)); + if (likely(ret == good_frame)) + ret = enh_desc_coe_rdes0(!!(rdes0 & RDES0_IPC_CSUM_ERROR), + !!(rdes0 & RDES0_FRAME_TYPE), + !!(rdes0 & ERDES0_RX_MAC_ADDR)); if (unlikely(rdes0 & RDES0_DRIBBLING)) x->dribbling_bit++; From 8ac0c24fe1c256af6644caf3d311029440ec2fbd Mon Sep 17 00:00:00 2001 From: Aaro Koskinen Date: Wed, 27 Mar 2019 22:35:39 +0200 Subject: [PATCH 5/6] net: stmmac: fix dropping of multi-descriptor RX frames Packets without the last descriptor set should be dropped early. If we receive a frame larger than the DMA buffer, the HW will continue using the next descriptor. Driver mistakes these as individual frames, and sometimes a truncated frame (without the LD set) may look like a valid packet. This fixes a strange issue where the system replies to 4098-byte ping although the MTU/DMA buffer size is set to 4096, and yet at the same time it's logging an oversized packet. Signed-off-by: Aaro Koskinen Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/enh_desc.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/ethernet/stmicro/stmmac/enh_desc.c b/drivers/net/ethernet/stmicro/stmmac/enh_desc.c index c42ef6c729c0..5202d6ad7919 100644 --- a/drivers/net/ethernet/stmicro/stmmac/enh_desc.c +++ b/drivers/net/ethernet/stmicro/stmmac/enh_desc.c @@ -201,6 +201,11 @@ static int enh_desc_get_rx_status(void *data, struct stmmac_extra_stats *x, if (unlikely(rdes0 & RDES0_OWN)) return dma_own; + if (unlikely(!(rdes0 & RDES0_LAST_DESCRIPTOR))) { + stats->rx_length_errors++; + return discard_frame; + } + if (unlikely(rdes0 & RDES0_ERROR_SUMMARY)) { if (unlikely(rdes0 & RDES0_DESCRIPTOR_ERROR)) { x->rx_desc++; From 057a0c5642a2ff2db7c421cdcde34294a23bf37b Mon Sep 17 00:00:00 2001 From: Aaro Koskinen Date: Wed, 27 Mar 2019 22:35:40 +0200 Subject: [PATCH 6/6] net: stmmac: don't log oversized frames This is log is harmful as it can trigger multiple times per packet. Delete it. Signed-off-by: Aaro Koskinen Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/norm_desc.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/norm_desc.c b/drivers/net/ethernet/stmicro/stmmac/norm_desc.c index c55a9815b394..b7dd4e3c760d 100644 --- a/drivers/net/ethernet/stmicro/stmmac/norm_desc.c +++ b/drivers/net/ethernet/stmicro/stmmac/norm_desc.c @@ -91,8 +91,6 @@ static int ndesc_get_rx_status(void *data, struct stmmac_extra_stats *x, return dma_own; if (unlikely(!(rdes0 & RDES0_LAST_DESCRIPTOR))) { - pr_warn("%s: Oversized frame spanned multiple buffers\n", - __func__); stats->rx_length_errors++; return discard_frame; }