Re: [PATCH net] netdevice: Fix promiscuity and allmulti negative overflow

[David Miller <davem@davemloft.net>]

From: Hangbin Liu <liuhangbin@gmail.com>
Date: Thu,  4 Apr 2019 20:45:18 +0800

> Similarly to dad9b335c694 ("netdevice: Fix promiscuity and allmulti
> overflow"), we should not decrease promiscuity if it is already 0.
> 
> An example is after adding a team interface to bridge, the team interface
> will enter promisc mode. Then if we add a slave to team0, the slave will
> keep promisc off. If we remove team from bridge, both team0 and slave will
> decrease the promiscuity, which will cause a negative overflow on the slave.
> The team's issue will be fixed in a separate patch.
> 
> Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>

These little hacks are endless.

I would rather see team and bridge and bonding appropriately keep the
promisc count adjusted as need when slaves are added/removed etc.

What is the point of the counter if it doesn't "count" properly?

I'm not applying this.

Because if I apply it, this just encourages more hackish workarounds
for the fundamental problem.