6.6-stable review patch. If anyone has any objections, please let me know.
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From: Sieng-Piaw Liew liew.s.piaw@gmail.com
[ Upstream commit 86565682e9053e5deb128193ea9e88531bbae9cf ]
This is based on alx driver commit 881d0327db37 ("net: alx: Work around the DMA RX overflow issue").
The alx and atl1c drivers had RX overflow error which was why a custom allocator was created to avoid certain addresses. The simpler workaround then created for alx driver, but not for atl1c due to lack of tester.
Instead of using a custom allocator, check the allocated skb address and use skb_reserve() to move away from problematic 0x...fc0 address.
Tested on AR8131 on Acer 4540.
Signed-off-by: Sieng-Piaw Liew liew.s.piaw@gmail.com Link: https://lore.kernel.org/r/20230912010711.12036-1-liew.s.piaw@gmail.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/atheros/atl1c/atl1c.h | 3 - .../net/ethernet/atheros/atl1c/atl1c_main.c | 67 +++++-------------- 2 files changed, 16 insertions(+), 54 deletions(-)
diff --git a/drivers/net/ethernet/atheros/atl1c/atl1c.h b/drivers/net/ethernet/atheros/atl1c/atl1c.h index 43d821fe7a542..63ba64dbb7310 100644 --- a/drivers/net/ethernet/atheros/atl1c/atl1c.h +++ b/drivers/net/ethernet/atheros/atl1c/atl1c.h @@ -504,15 +504,12 @@ struct atl1c_rrd_ring { u16 next_to_use; u16 next_to_clean; struct napi_struct napi; - struct page *rx_page; - unsigned int rx_page_offset; };
/* board specific private data structure */ struct atl1c_adapter { struct net_device *netdev; struct pci_dev *pdev; - unsigned int rx_frag_size; struct atl1c_hw hw; struct atl1c_hw_stats hw_stats; struct mii_if_info mii; /* MII interface info */ diff --git a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c index 940c5d1ff9cfc..74b78164cf74a 100644 --- a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c +++ b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c @@ -483,15 +483,10 @@ static int atl1c_set_mac_addr(struct net_device *netdev, void *p) static void atl1c_set_rxbufsize(struct atl1c_adapter *adapter, struct net_device *dev) { - unsigned int head_size; int mtu = dev->mtu;
adapter->rx_buffer_len = mtu > AT_RX_BUF_SIZE ? roundup(mtu + ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN, 8) : AT_RX_BUF_SIZE; - - head_size = SKB_DATA_ALIGN(adapter->rx_buffer_len + NET_SKB_PAD + NET_IP_ALIGN) + - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); - adapter->rx_frag_size = roundup_pow_of_two(head_size); }
static netdev_features_t atl1c_fix_features(struct net_device *netdev, @@ -964,7 +959,6 @@ static void atl1c_init_ring_ptrs(struct atl1c_adapter *adapter) static void atl1c_free_ring_resources(struct atl1c_adapter *adapter) { struct pci_dev *pdev = adapter->pdev; - int i;
dma_free_coherent(&pdev->dev, adapter->ring_header.size, adapter->ring_header.desc, adapter->ring_header.dma); @@ -977,12 +971,6 @@ static void atl1c_free_ring_resources(struct atl1c_adapter *adapter) kfree(adapter->tpd_ring[0].buffer_info); adapter->tpd_ring[0].buffer_info = NULL; } - for (i = 0; i < adapter->rx_queue_count; ++i) { - if (adapter->rrd_ring[i].rx_page) { - put_page(adapter->rrd_ring[i].rx_page); - adapter->rrd_ring[i].rx_page = NULL; - } - } }
/** @@ -1754,48 +1742,11 @@ static inline void atl1c_rx_checksum(struct atl1c_adapter *adapter, skb_checksum_none_assert(skb); }
-static struct sk_buff *atl1c_alloc_skb(struct atl1c_adapter *adapter, - u32 queue, bool napi_mode) -{ - struct atl1c_rrd_ring *rrd_ring = &adapter->rrd_ring[queue]; - struct sk_buff *skb; - struct page *page; - - if (adapter->rx_frag_size > PAGE_SIZE) { - if (likely(napi_mode)) - return napi_alloc_skb(&rrd_ring->napi, - adapter->rx_buffer_len); - else - return netdev_alloc_skb_ip_align(adapter->netdev, - adapter->rx_buffer_len); - } - - page = rrd_ring->rx_page; - if (!page) { - page = alloc_page(GFP_ATOMIC); - if (unlikely(!page)) - return NULL; - rrd_ring->rx_page = page; - rrd_ring->rx_page_offset = 0; - } - - skb = build_skb(page_address(page) + rrd_ring->rx_page_offset, - adapter->rx_frag_size); - if (likely(skb)) { - skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN); - rrd_ring->rx_page_offset += adapter->rx_frag_size; - if (rrd_ring->rx_page_offset >= PAGE_SIZE) - rrd_ring->rx_page = NULL; - else - get_page(page); - } - return skb; -} - static int atl1c_alloc_rx_buffer(struct atl1c_adapter *adapter, u32 queue, bool napi_mode) { struct atl1c_rfd_ring *rfd_ring = &adapter->rfd_ring[queue]; + struct atl1c_rrd_ring *rrd_ring = &adapter->rrd_ring[queue]; struct pci_dev *pdev = adapter->pdev; struct atl1c_buffer *buffer_info, *next_info; struct sk_buff *skb; @@ -1814,13 +1765,27 @@ static int atl1c_alloc_rx_buffer(struct atl1c_adapter *adapter, u32 queue, while (next_info->flags & ATL1C_BUFFER_FREE) { rfd_desc = ATL1C_RFD_DESC(rfd_ring, rfd_next_to_use);
- skb = atl1c_alloc_skb(adapter, queue, napi_mode); + /* When DMA RX address is set to something like + * 0x....fc0, it will be very likely to cause DMA + * RFD overflow issue. + * + * To work around it, we apply rx skb with 64 bytes + * longer space, and offset the address whenever + * 0x....fc0 is detected. + */ + if (likely(napi_mode)) + skb = napi_alloc_skb(&rrd_ring->napi, adapter->rx_buffer_len + 64); + else + skb = netdev_alloc_skb(adapter->netdev, adapter->rx_buffer_len + 64); if (unlikely(!skb)) { if (netif_msg_rx_err(adapter)) dev_warn(&pdev->dev, "alloc rx buffer failed\n"); break; }
+ if (((unsigned long)skb->data & 0xfff) == 0xfc0) + skb_reserve(skb, 64); + /* * Make buffer alignment 2 beyond a 16 byte boundary * this will result in a 16 byte aligned IP header after