diff options
| author | Juergen Gross <jgross@suse.com> | 2021-02-02 08:09:38 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-02-17 11:02:26 +0100 |
| commit | 50ad6fc36aed44d2b54c9530264e74caf051e5d2 (patch) | |
| tree | 0735e863cd7ffb49dda903ccd8fbb8f86fe84a0c | |
| parent | bbb8c391486b717ac880145a0e848b88af89416e (diff) | |
xen/netback: avoid race in xenvif_rx_ring_slots_available()
[ 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>
| -rw-r--r-- | drivers/net/xen-netback/rx.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/drivers/net/xen-netback/rx.c b/drivers/net/xen-netback/rx.c index b8febe1d1bfd..accc991d153f 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; |