From: Haiyue Wang <haiyue.wang@intel.com> stable inclusion from stable-5.10.65 commit f1673e85254d3dae8f595c0367cd33c73530952e bugzilla: 182361 https://gitee.com/openeuler/kernel/issues/I4EH3U Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 63a9192b8fa1ea55efeba1f18fad52bb24d9bf12 ] The 'tail' pointer is also free-running count, so it needs to be masked as 'adminq_prod_cnt' does, to become an index value of AdminQ buffer. Fixes: 5cdad90de62c ("gve: Batch AQ commands for creating and destroying queues.") Signed-off-by: Haiyue Wang <haiyue.wang@intel.com> Reviewed-by: Catherine Sullivan <csully@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- drivers/net/ethernet/google/gve/gve_adminq.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/google/gve/gve_adminq.c b/drivers/net/ethernet/google/gve/gve_adminq.c index 24ae6a28a806..6009d76e41fc 100644 --- a/drivers/net/ethernet/google/gve/gve_adminq.c +++ b/drivers/net/ethernet/google/gve/gve_adminq.c @@ -182,7 +182,8 @@ static int gve_adminq_issue_cmd(struct gve_priv *priv, tail = ioread32be(&priv->reg_bar0->adminq_event_counter); // Check if next command will overflow the buffer. - if (((priv->adminq_prod_cnt + 1) & priv->adminq_mask) == tail) { + if (((priv->adminq_prod_cnt + 1) & priv->adminq_mask) == + (tail & priv->adminq_mask)) { int err; // Flush existing commands to make room. @@ -192,7 +193,8 @@ static int gve_adminq_issue_cmd(struct gve_priv *priv, // Retry. tail = ioread32be(&priv->reg_bar0->adminq_event_counter); - if (((priv->adminq_prod_cnt + 1) & priv->adminq_mask) == tail) { + if (((priv->adminq_prod_cnt + 1) & priv->adminq_mask) == + (tail & priv->adminq_mask)) { // This should never happen. We just flushed the // command queue so there should be enough space. return -ENOMEM; -- 2.20.1