Re: [PATCH v1 net-next 0/2] dev: Hold per-netns RTNL in register_netdev().

[Kuniyuki Iwashima <kuniyu@amazon.com>]

From: Paolo Abeni <pabeni@redhat.com>
Date: Tue, 7 Jan 2025 13:55:51 +0100
> On 1/4/25 9:21 AM, Kuniyuki Iwashima wrote:
> > Patch 1 adds rtnl_net_lock_killable() and Patch 2 uses it in
> > register_netdev() and converts it and unregister_netdev() to
> > per-netns RTNL.
> > 
> > With this and the netdev notifier series [0], ASSERT_RTNL_NET()
> > for NETDEV_REGISTER [1] wasn't fired on a simplest QEMU setup
> > like e1000 + x86_64_defconfig + CONFIG_DEBUG_NET_SMALL_RTNL.
> > 
> > [0]: https://lore.kernel.org/netdev/20250104063735.36945-1-kuniyu@amazon.com/
> > 
> > [1]:
> > ---8<---
> > diff --git a/net/core/rtnl_net_debug.c b/net/core/rtnl_net_debug.c
> > index f406045cbd0e..c0c30929002e 100644
> > --- a/net/core/rtnl_net_debug.c
> > +++ b/net/core/rtnl_net_debug.c
> > @@ -21,7 +21,6 @@ static int rtnl_net_debug_event(struct notifier_block *nb,
> >  	case NETDEV_DOWN:
> >  	case NETDEV_REBOOT:
> >  	case NETDEV_CHANGE:
> > -	case NETDEV_REGISTER:
> >  	case NETDEV_UNREGISTER:
> >  	case NETDEV_CHANGEMTU:
> >  	case NETDEV_CHANGEADDR:
> > @@ -60,19 +59,10 @@ static int rtnl_net_debug_event(struct notifier_block *nb,
> >  		ASSERT_RTNL();
> >  		break;
> >  
> > -	/* Once an event fully supports RTNL_NET, move it here
> > -	 * and remove "if (0)" below.
> > -	 *
> > -	 * case NETDEV_XXX:
> > -	 *	ASSERT_RTNL_NET(net);
> > -	 *	break;
> > -	 */
> > -	}
> > -
> > -	/* Just to avoid unused-variable error for dev and net. */
> > -	if (0)
> > +	case NETDEV_REGISTER:
> >  		ASSERT_RTNL_NET(net);
> > +		break;
> > +	}
> >  
> >  	return NOTIFY_DONE;
> >  }
> > ---8<---
> 
> FTR, the above fooled a bit both PW and our scripts: I had to manually
> mangle the cover letter into the merge commit. I guess it would be good
> to avoid patch snips in the cover-letter,

Oh sorry, noted.

Thank you !