niu: panic on reset

The reset_task function in the niu driver does not reset the tx and rx
buffers properly. This leads to panic on reset. This patch is a
modified implementation of the previously posted fix.

Signed-off-by: Santwona Behera <santwona.behera@sun.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 56 insertions, 0 deletions

diff --git a/drivers/net/niu.c b/drivers/net/niu.c
index e4765b713aba..e3be81eba8a4 100644
--- a/drivers/net/niu.c
+++ b/drivers/net/niu.c
@@ -5984,6 +5984,56 @@ static void niu_netif_start(struct niu *np)
         niu_enable_interrupts(np, 1);
 }
 
+static void niu_reset_buffers(struct niu *np)
+{
+        int i, j, k, err;
+
+        if (np->rx_rings) {
+                for (i = 0; i < np->num_rx_rings; i++) {
+                        struct rx_ring_info *rp = &np->rx_rings[i];
+
+                        for (j = 0, k = 0; j < MAX_RBR_RING_SIZE; j++) {
+                                struct page *page;
+
+                                page = rp->rxhash[j];
+                                while (page) {
+                                        struct page *next =
+                                                (struct page *) page->mapping;
+                                        u64 base = page->index;
+                                        base = base >> RBR_DESCR_ADDR_SHIFT;
+                                        rp->rbr[k++] = cpu_to_le32(base);
+                                        page = next;
+                                }
+                        }
+                        for (; k < MAX_RBR_RING_SIZE; k++) {
+                                err = niu_rbr_add_page(np, rp, GFP_ATOMIC, k);
+                                if (unlikely(err))
+                                        break;
+                        }
+
+                        rp->rbr_index = rp->rbr_table_size - 1;
+                        rp->rcr_index = 0;
+                        rp->rbr_pending = 0;
+                        rp->rbr_refill_pending = 0;
+                }
+        }
+        if (np->tx_rings) {
+                for (i = 0; i < np->num_tx_rings; i++) {
+                        struct tx_ring_info *rp = &np->tx_rings[i];
+
+                        for (j = 0; j < MAX_TX_RING_SIZE; j++) {
+                                if (rp->tx_buffs[j].skb)
+                                        (void) release_tx_packet(np, rp, j);
+                        }
+
+                        rp->pending = MAX_TX_RING_SIZE;
+                        rp->prod = 0;
+                        rp->cons = 0;
+                        rp->wrap_bit = 0;
+                }
+        }
+}
+
 static void niu_reset_task(struct work_struct *work)
 {
         struct niu *np = container_of(work, struct niu, reset_task);
@@ -6006,6 +6056,12 @@ static void niu_reset_task(struct work_struct *work)
 
         niu_stop_hw(np);
 
+        spin_unlock_irqrestore(&np->lock, flags);
+
+        niu_reset_buffers(np);
+
+        spin_lock_irqsave(&np->lock, flags);
+
         err = niu_init_hw(np);
         if (!err) {
                 np->timer.expires = jiffies + HZ;