This is a note to let you know that I've just added the patch titled
virtio_net: fix oom handling on tx
to the 2.6.32-longterm tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/longterm/longterm-queue-2.6.32.git;a=summary
The filename of the patch is:
virtio_net-fix-oom-handling-on-tx.patch
and it can be found in the queue-2.6.32 subdirectory.
If you, or anyone else, feels it should not be added to the 2.6.32 longterm
tree,
please let <[email protected]> know about it.
>From e15ad900b96ffa7396be6aea5dea8f854b23d770 Mon Sep 17 00:00:00 2001
From: Rusty Russell <[email protected]>
Date: Fri, 2 Jul 2010 16:34:01 +0000
Subject: virtio_net: fix oom handling on tx
From: Rusty Russell <[email protected]>
commit 58eba97d0774c69b1cf3e5a8ac74419409d1abbf upstream.
virtio net will never try to overflow the TX ring, so the only reason
add_buf may fail is out of memory. Thus, we can not stop the
device until some request completes - there's no guarantee anything
at all is outstanding.
Make the error message clearer as well: error here does not
indicate queue full.
Signed-off-by: Michael S. Tsirkin <[email protected]>
Signed-off-by: Rusty Russell <[email protected]> (...and avoid TX_BUSY)
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
drivers/net/virtio_net.c | 21 +++++++++++++--------
1 file changed, 13 insertions(+), 8 deletions(-)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -525,7 +525,6 @@ static netdev_tx_t start_xmit(struct sk_
struct virtnet_info *vi = netdev_priv(dev);
int capacity;
-again:
/* Free up any pending old buffers before queueing new ones. */
free_old_xmit_skbs(vi);
@@ -534,14 +533,20 @@ again:
/* This can happen with OOM and indirect buffers. */
if (unlikely(capacity < 0)) {
- netif_stop_queue(dev);
- dev_warn(&dev->dev, "Unexpected full queue\n");
- if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
- vi->svq->vq_ops->disable_cb(vi->svq);
- netif_start_queue(dev);
- goto again;
+ if (net_ratelimit()) {
+ if (likely(capacity == -ENOMEM)) {
+ dev_warn(&dev->dev,
+ "TX queue failure: out of memory\n");
+ } else {
+ dev->stats.tx_fifo_errors++;
+ dev_warn(&dev->dev,
+ "Unexpected TX queue failure: %d\n",
+ capacity);
+ }
}
- return NETDEV_TX_BUSY;
+ dev->stats.tx_dropped++;
+ kfree_skb(skb);
+ return NETDEV_TX_OK;
}
vi->svq->vq_ops->kick(vi->svq);
Patches currently in longterm-queue-2.6.32 which might be from
[email protected] are
/home/gregkh/linux/longterm/longterm-queue-2.6.32/queue-2.6.32/virtio_net-fix-oom-handling-on-tx.patch
/home/gregkh/linux/longterm/longterm-queue-2.6.32/queue-2.6.32/virtio_net-add-schedule-check-to-napi_enable-call.patch
_______________________________________________
stable mailing list
[email protected]
http://linux.kernel.org/mailman/listinfo/stable
