be2net: Fix to avoid a crash seen on PPC with LRO and Jumbo frames.
While testing the driver on PPC, we ran into a crash with LRO, Jumbo frames.
With CONFIG_PPC_64K_PAGES configured (a default in PPC), MAX_SKB_FRAGS drops to 3 and we were crossing the array limits on skb_shinfo(skb)->frags[].
Now we coalesce the frags from the same physical page into one slot in
skb_shinfo(skb)->frags[] and go to the next index when the frag is from
different physical page.
This patch is against the net-2.6 tree.
Signed-off-by: Ajit Khaparde <ajitk@serverengines.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/benet/be.h b/drivers/net/benet/be.h
index f703758..5b4bf3d 100644
--- a/drivers/net/benet/be.h
+++ b/drivers/net/benet/be.h
@@ -73,7 +73,7 @@
#define RX_FRAGS_REFILL_WM (RX_Q_LEN - MAX_RX_POST)
#define BE_MAX_LRO_DESCRIPTORS 16
-#define BE_MAX_FRAGS_PER_FRAME 16
+#define BE_MAX_FRAGS_PER_FRAME (min((u32) 16, (u32) MAX_SKB_FRAGS))
struct be_dma_mem {
void *va;
diff --git a/drivers/net/benet/be_ethtool.c b/drivers/net/benet/be_ethtool.c
index 9592f22..cccc541 100644
--- a/drivers/net/benet/be_ethtool.c
+++ b/drivers/net/benet/be_ethtool.c
@@ -162,8 +162,8 @@
return -EINVAL;
adapter->max_rx_coal = coalesce->rx_max_coalesced_frames;
- if (adapter->max_rx_coal > MAX_SKB_FRAGS)
- adapter->max_rx_coal = MAX_SKB_FRAGS - 1;
+ if (adapter->max_rx_coal > BE_MAX_FRAGS_PER_FRAME)
+ adapter->max_rx_coal = BE_MAX_FRAGS_PER_FRAME;
/* if AIC is being turned on now, start with an EQD of 0 */
if (rx_eq->enable_aic == 0 &&
diff --git a/drivers/net/benet/be_main.c b/drivers/net/benet/be_main.c
index 66c10c8..308eb09 100644
--- a/drivers/net/benet/be_main.c
+++ b/drivers/net/benet/be_main.c
@@ -666,7 +666,7 @@
{
struct be_queue_info *rxq = &adapter->rx_obj.q;
struct be_rx_page_info *page_info;
- u16 rxq_idx, i, num_rcvd;
+ u16 rxq_idx, i, num_rcvd, j;
u32 pktsize, hdr_len, curr_frag_len;
u8 *start;
@@ -709,22 +709,33 @@
/* More frags present for this completion */
pktsize -= curr_frag_len; /* account for above copied frag */
- for (i = 1; i < num_rcvd; i++) {
+ for (i = 1, j = 0; i < num_rcvd; i++) {
index_inc(&rxq_idx, rxq->len);
page_info = get_rx_page_info(adapter, rxq_idx);
curr_frag_len = min(pktsize, rx_frag_size);
- skb_shinfo(skb)->frags[i].page = page_info->page;
- skb_shinfo(skb)->frags[i].page_offset = page_info->page_offset;
- skb_shinfo(skb)->frags[i].size = curr_frag_len;
+ /* Coalesce all frags from the same physical page in one slot */
+ if (page_info->page_offset == 0) {
+ /* Fresh page */
+ j++;
+ skb_shinfo(skb)->frags[j].page = page_info->page;
+ skb_shinfo(skb)->frags[j].page_offset =
+ page_info->page_offset;
+ skb_shinfo(skb)->frags[j].size = 0;
+ skb_shinfo(skb)->nr_frags++;
+ } else {
+ put_page(page_info->page);
+ }
+
+ skb_shinfo(skb)->frags[j].size += curr_frag_len;
skb->len += curr_frag_len;
skb->data_len += curr_frag_len;
- skb_shinfo(skb)->nr_frags++;
pktsize -= curr_frag_len;
memset(page_info, 0, sizeof(*page_info));
}
+ BUG_ON(j > MAX_SKB_FRAGS);
done:
be_rx_stats_update(adapter, pktsize, num_rcvd);
@@ -786,7 +797,7 @@
struct skb_frag_struct rx_frags[BE_MAX_FRAGS_PER_FRAME];
struct be_queue_info *rxq = &adapter->rx_obj.q;
u32 num_rcvd, pkt_size, remaining, vlanf, curr_frag_len;
- u16 i, rxq_idx = 0, vid;
+ u16 i, rxq_idx = 0, vid, j;
num_rcvd = AMAP_GET_BITS(struct amap_eth_rx_compl, numfrags, rxcp);
pkt_size = AMAP_GET_BITS(struct amap_eth_rx_compl, pktsize, rxcp);
@@ -794,20 +805,28 @@
rxq_idx = AMAP_GET_BITS(struct amap_eth_rx_compl, fragndx, rxcp);
remaining = pkt_size;
- for (i = 0; i < num_rcvd; i++) {
+ for (i = 0, j = -1; i < num_rcvd; i++) {
page_info = get_rx_page_info(adapter, rxq_idx);
curr_frag_len = min(remaining, rx_frag_size);
- rx_frags[i].page = page_info->page;
- rx_frags[i].page_offset = page_info->page_offset;
- rx_frags[i].size = curr_frag_len;
+ /* Coalesce all frags from the same physical page in one slot */
+ if (i == 0 || page_info->page_offset == 0) {
+ /* First frag or Fresh page */
+ j++;
+ rx_frags[j].page = page_info->page;
+ rx_frags[j].page_offset = page_info->page_offset;
+ rx_frags[j].size = 0;
+ } else {
+ put_page(page_info->page);
+ }
+ rx_frags[j].size += curr_frag_len;
+
remaining -= curr_frag_len;
-
index_inc(&rxq_idx, rxq->len);
-
memset(page_info, 0, sizeof(*page_info));
}
+ BUG_ON(j > MAX_SKB_FRAGS);
if (likely(!vlanf)) {
lro_receive_frags(&adapter->rx_obj.lro_mgr, rx_frags, pkt_size,