Re: [PATCH net v2] net: usb: Remove disruptive netif_wake_queue in rtl8150_set_multicast

Jakub Kicinski
2025-09-23T14:28:10Z

On Tue, 23 Sep 2025 09:47:11 +0200 Michal Pecio wrote:
> On Mon, 22 Sep 2025 18:07:42 -0700, Jakub Kicinski wrote:
> > On Sat, 20 Sep 2025 23:48:52 +0530 I Viswanath wrote:
> > > rtl8150_set_multicast is rtl8150's implementation of ndo_set_rx_mode and
> > > should not be calling netif_stop_queue and notif_start_queue as these handle
> > > TX queue synchronization.
> > >
> > > The net core function dev_set_rx_mode handles the synchronization
> > > for rtl8150_set_multicast making it safe to remove these locks.
> >
> > Last time someone tried to add device ID to this driver was 20 years
> > ago. Please post a patch to delete this driver completely. If someone
> > speaks up we'll revert the removal and ask them to test the fix.
>
> These were quite common, I still have one.
>
> What sort of testing do you need?

Excellent, could you check if there is any adverse effect of repeatedly
writing the RCR register under heavy Tx traffic (without stopping/waking
the Tx queue)? The driver seems to pause Tx when RCR is written, seems
like an odd thing to do without a reason, but driver authors do the
darndest things.