Commit 7b84ab85 authored by Tong Zhang's avatar Tong Zhang Committed by Greg Kroah-Hartman
Browse files

staging: rtl8192u: fix rmmod warn when device is renamed 



This driver creates 4 debug files under [devname] folder. The devname
could be wlan0 initially, however it could be renamed later to e.g.
enx00e04c00000. This will cause problem during debug file teardown since
it uses netdev->name, which is no longer wlan0. To solve this problem,
add a notifier to handle device renaming. Also note that we cannot
simply do debugfs_lookup to find out old dentry since by the time the
notifier is called, netdev->name is already changed to new name.

Reported-by: default avatarZheyu Ma <zheyuma97@gmail.com>
Tested-by: default avatarZheyu Ma <zheyuma97@gmail.com>
Reviewed-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarTong Zhang <ztong0001@gmail.com>
Link: https://lore.kernel.org/r/20220730033335.74153-5-ztong0001@gmail.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent c5682c05

drivers/staging/rtl8192u/r8192U.h

+1 −0
Original line number Diff line number Diff line
@@ -1122,6 +1122,7 @@ void setKey(struct net_device *dev, u8 EntryNo, u8 KeyIndex, u16 KeyType, 


void rtl8192_debugfs_init_one(struct net_device *dev);

void rtl8192_debugfs_exit_one(struct net_device *dev);

void rtl8192_debugfs_rename_one(struct net_device *dev);

void rtl8192_debugfs_init(void);

void rtl8192_debugfs_exit(void);

drivers/staging/rtl8192u/r8192U_core.c

+32 −0
Original line number Diff line number Diff line
@@ -4606,6 +4606,30 @@ static void rtl8192_usb_disconnect(struct usb_interface *intf) 
	RT_TRACE(COMP_DOWN, "wlan driver removed\n");

}



static int rtl8192_usb_netdev_event(struct notifier_block *nb, unsigned long event,

				    void *data)

{

	struct net_device *netdev = netdev_notifier_info_to_dev(data);



	if (netdev->netdev_ops != &rtl8192_netdev_ops)

		goto out;



	switch (event) {

	case NETDEV_CHANGENAME:

		rtl8192_debugfs_rename_one(netdev);

		break;

	default:

		break;

	}



out:

	return NOTIFY_DONE;

}



static struct notifier_block rtl8192_usb_netdev_notifier = {

	.notifier_call = rtl8192_usb_netdev_event,

};



static int __init rtl8192_usb_module_init(void)

{

	int ret;
@@ -4615,6 +4639,12 @@ static int __init rtl8192_usb_module_init(void) 
	RT_TRACE(COMP_INIT, "Initializing module");

	RT_TRACE(COMP_INIT, "Wireless extensions version %d", WIRELESS_EXT);



	ret = register_netdevice_notifier(&rtl8192_usb_netdev_notifier);

	if (ret) {

		pr_err("register_netdevice_notifier failed %d\n", ret);

		return ret;

	}



	rtl8192_debugfs_init();

	ret = ieee80211_debug_init();

	if (ret) {
@@ -4663,6 +4693,7 @@ static int __init rtl8192_usb_module_init(void) 
	ieee80211_debug_exit();

debugfs_exit:

	rtl8192_debugfs_exit();

	unregister_netdevice_notifier(&rtl8192_usb_netdev_notifier);

	return ret;

}
@@ -4675,6 +4706,7 @@ static void __exit rtl8192_usb_module_exit(void) 
	ieee80211_crypto_deinit();

	ieee80211_debug_exit();

	rtl8192_debugfs_exit();

	unregister_netdevice_notifier(&rtl8192_usb_netdev_notifier);

	RT_TRACE(COMP_DOWN, "Exiting");

}

drivers/staging/rtl8192u/r8192U_debugfs.c

+8 −0
Original line number Diff line number Diff line
@@ -169,6 +169,14 @@ void rtl8192_debugfs_exit_one(struct net_device *dev) 
	debugfs_remove_recursive(priv->debugfs_dir);

}



void rtl8192_debugfs_rename_one(struct net_device *dev)

{

	struct r8192_priv *priv = ieee80211_priv(dev);

	struct dentry *parent_dir = debugfs_lookup(KBUILD_MODNAME, NULL);



	debugfs_rename(parent_dir, priv->debugfs_dir, parent_dir, dev->name);

}



void rtl8192_debugfs_init(void)

{

	debugfs_create_dir(KBUILD_MODNAME, NULL);