From: Francois Romieu <romieu@fr.zoreil.com>
If the Rx buffer gets corrupted or the FIFO hangs in new interesting ways,
this code prevents the driver from looping in ksoftirqd context without
making any progress.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/drivers/net/8139too.c | 25 ++++++++++++++++++++++++-
1 files changed, 24 insertions(+), 1 deletion(-)
diff -puN drivers/net/8139too.c~8139too-be-sure-to-progress-durin-rtl8139_rx drivers/net/8139too.c
--- 25/drivers/net/8139too.c~8139too-be-sure-to-progress-durin-rtl8139_rx Thu Aug 5 16:14:12 2004
+++ 25-akpm/drivers/net/8139too.c Thu Aug 5 16:14:12 2004
@@ -593,6 +593,7 @@ struct rtl8139_private {
int time_to_die;
struct mii_if_info mii;
unsigned int regs_len;
+ unsigned long fifo_copy_timeout;
};
MODULE_AUTHOR ("Jeff Garzik <jgarzik@pobox.com>");
@@ -1937,7 +1938,7 @@ static int rtl8139_rx(struct net_device
u16 status;
DPRINTK ("%s: In rtl8139_rx(), current %4.4x BufAddr %4.4x,"
- " free to %4.4x, Cmd %2.2x.\n", dev->name, cur_rx,
+ " free to %4.4x, Cmd %2.2x.\n", dev->name, (u16)cur_rx,
RTL_R16 (RxBufAddr),
RTL_R16 (RxBufPtr), RTL_R8 (ChipCmd));
@@ -1978,10 +1979,24 @@ static int rtl8139_rx(struct net_device
* since EarlyRx is disabled.
*/
if (unlikely(rx_size == 0xfff0)) {
+ if (!tp->fifo_copy_timeout)
+ tp->fifo_copy_timeout = jiffies + 2;
+ else if (time_after(jiffies, tp->fifo_copy_timeout)) {
+ DPRINTK ("%s: hung FIFO. Reset.", dev->name);
+ rx_size = 0;
+ goto no_early_rx;
+ }
+ if (netif_msg_intr(tp)) {
+ printk(KERN_DEBUG "%s: fifo copy in progress.",
+ dev->name);
+ }
tp->xstats.early_rx++;
break;
}
+no_early_rx:
+ tp->fifo_copy_timeout = 0;
+
/* If Rx err or invalid rx_size/rx_status received
* (which happens if we get lost in the ring),
* Rx process gets reset, so we abort any further
@@ -2047,6 +2062,14 @@ static int rtl8139_rx(struct net_device
#endif
tp->cur_rx = cur_rx;
+
+ /*
+ * The receive buffer should be mostly empty.
+ * Tell NAPI to reenable the Rx irq.
+ */
+ if (tp->fifo_copy_timeout)
+ received = budget;
+
out:
return received;
}
_