From 94f950c4060cd9b1989c565284beb159b9705a50 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Tue, 11 Jun 2013 11:00:34 +0100 Subject: [PATCH] xen-netback: don't de-reference vif pointer after having called xenvif_put() When putting vif-s on the rx notify list, calling xenvif_put() must be deferred until after the removal from the list and the issuing of the notification, as both operations dereference the pointer. Changing this got me to notice that the "irq" variable was effectively unused (and was of too narrow type anyway). Signed-off-by: Jan Beulich Acked-by: Ian Campbell Signed-off-by: David S. Miller --- drivers/net/xen-netback/netback.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 37984e6d4e99..8c20935d72c9 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -662,7 +662,7 @@ static void xen_netbk_rx_action(struct xen_netbk *netbk) { struct xenvif *vif = NULL, *tmp; s8 status; - u16 irq, flags; + u16 flags; struct xen_netif_rx_response *resp; struct sk_buff_head rxq; struct sk_buff *skb; @@ -771,13 +771,13 @@ static void xen_netbk_rx_action(struct xen_netbk *netbk) sco->meta_slots_used); RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->rx, ret); - irq = vif->irq; - if (ret && list_empty(&vif->notify_list)) - list_add_tail(&vif->notify_list, ¬ify); xenvif_notify_tx_completion(vif); - xenvif_put(vif); + if (ret && list_empty(&vif->notify_list)) + list_add_tail(&vif->notify_list, ¬ify); + else + xenvif_put(vif); npo.meta_cons += sco->meta_slots_used; dev_kfree_skb(skb); } @@ -785,6 +785,7 @@ static void xen_netbk_rx_action(struct xen_netbk *netbk) list_for_each_entry_safe(vif, tmp, ¬ify, notify_list) { notify_remote_via_irq(vif->irq); list_del_init(&vif->notify_list); + xenvif_put(vif); } /* More work to do? */ -- 2.34.1