From: Juergen Gross jgross@suse.com
[ Upstream commit ec7d8e7dd3a59528e305a18e93f1cb98f7faf83b ]
Since commit 23025393dbeb3b8b3 ("xen/netback: use lateeoi irq binding") xenvif_rx_ring_slots_available() is no longer called only from the rx queue kernel thread, so it needs to access the rx queue with the associated queue held.
Reported-by: Igor Druzhinin igor.druzhinin@citrix.com Fixes: 23025393dbeb3b8b3 ("xen/netback: use lateeoi irq binding") Signed-off-by: Juergen Gross jgross@suse.com Acked-by: Wei Liu wl@xen.org Link: https://lore.kernel.org/r/20210202070938.7863-1-jgross@suse.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/xen-netback/rx.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/net/xen-netback/rx.c b/drivers/net/xen-netback/rx.c index 9b62f65b630e4..48e2006f96ce6 100644 --- a/drivers/net/xen-netback/rx.c +++ b/drivers/net/xen-netback/rx.c @@ -38,10 +38,15 @@ static bool xenvif_rx_ring_slots_available(struct xenvif_queue *queue) RING_IDX prod, cons; struct sk_buff *skb; int needed; + unsigned long flags; + + spin_lock_irqsave(&queue->rx_queue.lock, flags);
skb = skb_peek(&queue->rx_queue); - if (!skb) + if (!skb) { + spin_unlock_irqrestore(&queue->rx_queue.lock, flags); return false; + }
needed = DIV_ROUND_UP(skb->len, XEN_PAGE_SIZE); if (skb_is_gso(skb)) @@ -49,6 +54,8 @@ static bool xenvif_rx_ring_slots_available(struct xenvif_queue *queue) if (skb->sw_hash) needed++;
+ spin_unlock_irqrestore(&queue->rx_queue.lock, flags); + do { prod = queue->rx.sring->req_prod; cons = queue->rx.req_cons;