From 88a810def754d5516252b9a8b9efc34d875d399f Mon Sep 17 00:00:00 2001 From: Wei Liu Date: Mon, 2 Dec 2013 17:49:54 +0000 Subject: [PATCH] xen-netback: fix refcnt unbalance for 3.10 With the introduction of "xen-netback: Don't destroy the netdev until the vif is shut down" (upstream commit id 279f438e36), vif disconnect and free are separated. However in the backported version reference counting code was not correctly modified, and the reset of vif->irq was lost. If frontend goes through vif life cycle more than once the reference counting is skewed. This patch adds back the missing vif->irq reset line. It also moves several lines of the reference counting code to vif_free, so the moved code corresponds to the counterpart in vif_alloc, thus the reference counting is balanced. Signed-off-by: Wei Liu Acked-by: Ian Campbell Cc: Konrad Wilk Cc: David Vrabel Signed-off-by: Greg Kroah-Hartman --- drivers/net/xen-netback/interface.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index c4a2eb2..540a796 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -365,17 +365,19 @@ void xenvif_disconnect(struct xenvif *vif) if (netif_carrier_ok(vif->dev)) xenvif_carrier_off(vif); - atomic_dec(&vif->refcnt); - wait_event(vif->waiting_to_free, atomic_read(&vif->refcnt) == 0); - - if (vif->irq) + if (vif->irq) { unbind_from_irqhandler(vif->irq, vif); + vif->irq = 0; + } xen_netbk_unmap_frontend_rings(vif); } void xenvif_free(struct xenvif *vif) { + atomic_dec(&vif->refcnt); + wait_event(vif->waiting_to_free, atomic_read(&vif->refcnt) == 0); + unregister_netdev(vif->dev); free_netdev(vif->dev); -- 2.7.4