linux/debian/patches/bugfix/all/xen-netback-move-netif_napi...

58 lines
2.1 KiB
Diff

From 7ffe40b3013c6c4d66ebbc9a946173013a590a61 Mon Sep 17 00:00:00 2001
From: Wei Liu <wei.liu2@citrix.com>
Date: Mon, 25 Aug 2014 16:44:00 +0100
Subject: [PATCH 11/14] xen-netback: move netif_napi_add before binding
interrupt
Origin: https://git.kernel.org/linus/e24f8191cc35ae3780b4656a6befae8b8657edc2
Interrupt is enabled when bind_interdomain_evtchn_to_irqhandler returns.
If there's interrupt pending interrupt handler is invoked.
NAPI needs to be initialised before binding interrupt otherwise the
interrupt handler will try to scheduling a NAPI instance that is not
initialised yet, resulting in kernel OOPS.
This fixes a regression introduced in ea2c5e13 ("xen-netback: move NAPI
add/remove calls").
Ideally function calls to create kthreads should also be moved before
binding but I intent to fix this regression with minimal changes and
refactor the code with another patch.
Reported-by: Thomas Leonard <talex5@gmail.com>
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit e24f8191cc35ae3780b4656a6befae8b8657edc2)
---
drivers/net/xen-netback/interface.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c
index 10d832a..18cdc81 100644
--- a/drivers/net/xen-netback/interface.c
+++ b/drivers/net/xen-netback/interface.c
@@ -576,6 +576,9 @@ int xenvif_connect(struct xenvif_queue *queue, unsigned long tx_ring_ref,
init_waitqueue_head(&queue->dealloc_wq);
atomic_set(&queue->inflight_packets, 0);
+ netif_napi_add(queue->vif->dev, &queue->napi, xenvif_poll,
+ XENVIF_NAPI_WEIGHT);
+
if (tx_evtchn == rx_evtchn) {
/* feature-split-event-channels == 0 */
err = bind_interdomain_evtchn_to_irqhandler(
@@ -629,9 +632,6 @@ int xenvif_connect(struct xenvif_queue *queue, unsigned long tx_ring_ref,
wake_up_process(queue->task);
wake_up_process(queue->dealloc_task);
- netif_napi_add(queue->vif->dev, &queue->napi, xenvif_poll,
- XENVIF_NAPI_WEIGHT);
-
return 0;
err_rx_unbind:
--
1.7.10.4