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net/sonic: Improve receive descriptor status flag check

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After sonic_tx_timeout() calls sonic_init(), it can happen that
sonic_rx() will subsequently encounter a receive descriptor with no
flags set. Remove the comment that says that this can't happen.

When giving a receive descriptor to the SONIC, clear the descriptor
status field. That way, any rx descriptor with flags set can only be
a newly received packet.

Don't process a descriptor without the LPKT bit set. The buffer is
still in use by the SONIC.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Finn Thain 2020-01-23 09:07:26 +11:00 committed by David S. Miller
parent eaabfd19b2
commit 94b1663495
1 changed files with 5 additions and 10 deletions
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15
drivers/net/ethernet/natsemi/sonic.c
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@ -434,7 +434,6 @@ static int index_from_addr(struct sonic_local *lp, dma_addr_t addr,
static void sonic_rx(struct net_device *dev) static void sonic_rx(struct net_device *dev)
{ {
struct sonic_local *lp = netdev_priv(dev); struct sonic_local *lp = netdev_priv(dev);
int status;
int entry = lp->cur_rx; int entry = lp->cur_rx;
int prev_entry = lp->eol_rx; int prev_entry = lp->eol_rx;
@ -445,9 +444,10 @@ static void sonic_rx(struct net_device *dev)
u16 bufadr_l; u16 bufadr_l;
u16 bufadr_h; u16 bufadr_h;
int pkt_len; int pkt_len;
u16 status = sonic_rda_get(dev, entry, SONIC_RD_STATUS);
status = sonic_rda_get(dev, entry, SONIC_RD_STATUS); /* If the RD has LPKT set, the chip has finished with the RB */
if (status & SONIC_RCR_PRX) { if ((status & SONIC_RCR_PRX) && (status & SONIC_RCR_LPKT)) {
u32 addr = (sonic_rda_get(dev, entry, u32 addr = (sonic_rda_get(dev, entry,
SONIC_RD_PKTPTR_H) << 16) | SONIC_RD_PKTPTR_H) << 16) |
sonic_rda_get(dev, entry, SONIC_RD_PKTPTR_L); sonic_rda_get(dev, entry, SONIC_RD_PKTPTR_L);
@ -495,10 +495,6 @@ static void sonic_rx(struct net_device *dev)
bufadr_h = (unsigned long)new_laddr >> 16; bufadr_h = (unsigned long)new_laddr >> 16;
sonic_rra_put(dev, i, SONIC_RR_BUFADR_L, bufadr_l); sonic_rra_put(dev, i, SONIC_RR_BUFADR_L, bufadr_l);
sonic_rra_put(dev, i, SONIC_RR_BUFADR_H, bufadr_h); sonic_rra_put(dev, i, SONIC_RR_BUFADR_H, bufadr_h);
} else {
/* This should only happen, if we enable accepting broken packets. */
}
if (status & SONIC_RCR_LPKT) {
/* /*
* this was the last packet out of the current receive buffer * this was the last packet out of the current receive buffer
* give the buffer back to the SONIC * give the buffer back to the SONIC
@ -511,12 +507,11 @@ static void sonic_rx(struct net_device *dev)
__func__); __func__);
SONIC_WRITE(SONIC_ISR, SONIC_INT_RBE); /* clear the flag */ SONIC_WRITE(SONIC_ISR, SONIC_INT_RBE); /* clear the flag */
} }
} else }
printk(KERN_ERR "%s: rx desc without RCR_LPKT. Shouldn't happen !?\n",
dev->name);
/* /*
* give back the descriptor * give back the descriptor
*/ */
sonic_rda_put(dev, entry, SONIC_RD_STATUS, 0);
sonic_rda_put(dev, entry, SONIC_RD_IN_USE, 1); sonic_rda_put(dev, entry, SONIC_RD_IN_USE, 1);
prev_entry = entry; prev_entry = entry;