Re: [PATCH 6.6 3/3] net: Allow to use SMP threads for backlog NAPI.

From: Greg Kroah-Hartman

Date: Tue Jan 20 2026 - 01:04:02 EST


On Mon, Jan 19, 2026 at 05:30:26PM +0100, Sebastian Andrzej Siewior wrote:
> On 2026-01-19 08:25:34 [-0800], Jakub Kicinski wrote:
> > On Mon, 19 Jan 2026 00:15:46 +0800 wen.yang@xxxxxxxxx wrote:
> > > From: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
> > >
> > > commit dad6b97702639fba27a2bd3e986982ad6f0db3a7 upstream.
> > >
> > > Backlog NAPI is a per-CPU NAPI struct only (with no device behind it)
> > > used by drivers which don't do NAPI them self, RPS and parts of the
> > > stack which need to avoid recursive deadlocks while processing a packet.
> >
> > This is a rather large change to backport into LTS.
>
> I agree. While I saw these patches flying by, I don't remember a mail
> where it was justified why it was needed. Did I miss it?

Please see patch 0/3 in this series:
https://lore.kernel.org/all/cover.1768751557.git.wen.yang@xxxxxxxxx/