The following call chains indicate that chnl_net_open() is under rtnl_lock protection as __dev_open() is protected by rtnl_lock. So if __dev_get_by_index() instead of dev_get_by_index() is used to find interface handler in it, this would help us avoid to change interface reference counter.
__dev_open() chnl_net_open() Cc: Dmitry Tarnyagin <dmitry.tarnya...@lockless.no> Signed-off-by: Ying Xue <ying....@windriver.com> --- net/caif/chnl_net.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/net/caif/chnl_net.c b/net/caif/chnl_net.c index 7344a8f..4589ff67 100644 --- a/net/caif/chnl_net.c +++ b/net/caif/chnl_net.c @@ -285,7 +285,7 @@ static int chnl_net_open(struct net_device *dev) goto error; } - lldev = dev_get_by_index(dev_net(dev), llifindex); + lldev = __dev_get_by_index(dev_net(dev), llifindex); if (lldev == NULL) { pr_debug("no interface?\n"); @@ -307,7 +307,6 @@ static int chnl_net_open(struct net_device *dev) mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom)); mtu = min_t(int, GPRS_PDP_MTU, mtu); dev_set_mtu(dev, mtu); - dev_put(lldev); if (mtu < 100) { pr_warn("CAIF Interface MTU too small (%d)\n", mtu); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/