diff mbox series

[net-next,v5,02/10] net: free_netdev: exit earlier if dummy

Message ID 20240410131407.3897251-3-leitao@debian.org (mailing list archive)
State Not Applicable
Delegated to: Kalle Valo
Headers show
Series allocate dummy device dynamically | expand

Commit Message

Breno Leitao April 10, 2024, 1:13 p.m. UTC
For dummy devices, exit earlier at free_netdev() instead of executing
the whole function. This is necessary, because dummy devices are
special, and shouldn't have the second part of the function executed.

Otherwise reg_state, which is NETREG_DUMMY, will be overwritten and
there will be no way to identify that this is a dummy device. Also, this
device do not need the final put_device(), since dummy devices are not
registered (through register_netdevice()), where the device reference is
increased (at netdev_register_kobject()/device_add()).

Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Breno Leitao <leitao@debian.org>
---
 net/core/dev.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Ido Schimmel April 10, 2024, 3:05 p.m. UTC | #1
On Wed, Apr 10, 2024 at 06:13:43AM -0700, Breno Leitao wrote:
> For dummy devices, exit earlier at free_netdev() instead of executing
> the whole function. This is necessary, because dummy devices are
> special, and shouldn't have the second part of the function executed.
> 
> Otherwise reg_state, which is NETREG_DUMMY, will be overwritten and
> there will be no way to identify that this is a dummy device. Also, this
> device do not need the final put_device(), since dummy devices are not
> registered (through register_netdevice()), where the device reference is
> increased (at netdev_register_kobject()/device_add()).
> 
> Suggested-by: Jakub Kicinski <kuba@kernel.org>
> Signed-off-by: Breno Leitao <leitao@debian.org>

Reviewed-by: Ido Schimmel <idosch@nvidia.com>
diff mbox series

Patch

diff --git a/net/core/dev.c b/net/core/dev.c
index 987039ffa63c..c74b42bc6888 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -11060,7 +11060,8 @@  void free_netdev(struct net_device *dev)
 	phy_link_topo_destroy(dev->link_topo);
 
 	/*  Compatibility with error handling in drivers */
-	if (dev->reg_state == NETREG_UNINITIALIZED) {
+	if (dev->reg_state == NETREG_UNINITIALIZED ||
+	    dev->reg_state == NETREG_DUMMY) {
 		netdev_freemem(dev);
 		return;
 	}