Re: [PATCH net v2 1/2] Revert "r8152: napi hangup fix after disconnect"

From: Hayes Wang <redacted>
Date: Mon, 26 Aug 2019 09:43:32 +0000

Jiri Slaby [mailto:jslaby@suse.cz]

quoted

Sent: Monday, August 26, 2019 4:55 PM

[...]

quoted

Could you clarify *why* it conflicts? And how is the problem fixed by
0ee1f473496 avoided now?

In rtl8152_disconnect(), the flow would be as following.

static void rtl8152_disconnect(struct usb_interface *intf)
{
	...
	- netif_napi_del(&tp->napi);
	- unregister_netdev(tp->netdev);
	   - rtl8152_close
	      - napi_disable

Therefore you add a checking of RTL8152_UNPLUG to avoid
calling napi_disable() after netif_napi_del(). However,
after commit ffa9fec30ca0 ("r8152: set RTL8152_UNPLUG
only for real disconnection"), RTL8152_UNPLUG is not
always set when calling rtl8152_disconnect(). That is,
napi_disable() would be called after netif_napi_del(),
if RTL8152_UNPLUG is not set.

The best way is to avoid calling netif_napi_del() before
calling unregister_netdev(). And I has submitted such
patch following this one.

These details belong in the commit message, always.