diff options
author | Juergen Gross <jgross@suse.com> | 2021-02-02 08:09:38 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-02-23 13:59:16 +0100 |
commit | 7ee20fd8a8976c72d60af4f085f7dacfd8e29cce (patch) | |
tree | 88c6e7368e869045f10ca211e018098632048f9a /drivers/net/xen-netback | |
parent | dd07df94e62ee60446adc4790467af66577e2c12 (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>
Diffstat (limited to 'drivers/net/xen-netback')
-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 f152246c7dfb..ddfb1cfa2dd9 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; |