[PATCH net-next v2 08/10] caif: __dev_get_by_index instead of dev_get_by_index to find interface

From: Ying Xue
Date: Tue Jan 14 2014 - 21:25:47 EST


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.tarnyagin@xxxxxxxxxxx>
Signed-off-by: Ying Xue <ying.xue@xxxxxxxxxxxxx>
---
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 majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/