From 059dfa6a93b779516321e5112db9d7621b1367ba Mon Sep 17 00:00:00 2001 From: Wei Liu Date: Mon, 28 Oct 2013 12:07:57 +0000 Subject: xen-netback: use jiffies_64 value to calculate credit timeout time_after_eq() only works if the delta is < MAX_ULONG/2. For a 32bit Dom0, if netfront sends packets at a very low rate, the time between subsequent calls to tx_credit_exceeded() may exceed MAX_ULONG/2 and the test for timer_after_eq() will be incorrect. Credit will not be replenished and the guest may become unable to send packets (e.g., if prior to the long gap, all credit was exhausted). Use jiffies_64 variant to mitigate this problem for 32bit Dom0. Suggested-by: Jan Beulich Signed-off-by: Wei Liu Reviewed-by: David Vrabel Cc: Ian Campbell Cc: Jason Luan Signed-off-by: David S. Miller --- drivers/net/xen-netback/interface.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/net/xen-netback/interface.c') diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 01bb854c7f6..459935a6bfa 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -312,8 +312,7 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, vif->credit_bytes = vif->remaining_credit = ~0UL; vif->credit_usec = 0UL; init_timer(&vif->credit_timeout); - /* Initialize 'expires' now: it's used to track the credit window. */ - vif->credit_timeout.expires = jiffies; + vif->credit_window_start = get_jiffies_64(); dev->netdev_ops = &xenvif_netdev_ops; dev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_TSO; -- cgit v1.2.3-70-g09d2