Re: [PATCH net-next 0/2] net: netconsole: convert to NBCON console infrastructure

From: Breno Leitao

Date: Tue Dec 23 2025 - 05:08:29 EST


On Tue, Dec 23, 2025 at 08:12:08AM +0100, Paolo Abeni wrote:
> On 12/22/25 3:52 PM, Breno Leitao wrote:
> > This series adds support for the nbcon (new buffer console) infrastructure
> > to netconsole, enabling lock-free, priority-based console operations that
> > are safer in crash scenarios.
> >
> > The implementation is introduced in three steps:
> >
> > 1) Refactor the message fragmentation logic into a reusable helper function
> > 2) Extend nbcon support to non-extended (basic) consoles using the same
> > infrastructure.
> >
> > The initial discussion about it appeared a while ago in [1], in order to
> > solve Mike's HARDIRQ-safe -> HARDIRQ-unsafe lock order warning, and the root
> > cause is that some hosts were calling IRQ unsafe locks from inside console
> > lock.
> >
> > At that time, we didn't have the CON_NBCON_ATOMIC_UNSAFE yet. John
> > kindly implemented CON_NBCON_ATOMIC_UNSAFE in 187de7c212e5 ("printk:
> > nbcon: Allow unsafe write_atomic() for panic"), and now we can
> > implement netconsole on top of nbcon.
> >
> > Important to note that netconsole continues to call netpoll and the
> > network TX helpers with interrupt disable, given the TX are called with
> > target_list_lock.
> >
> > Link:
> > https://lore.kernel.org/all/b2qps3uywhmjaym4mht2wpxul4yqtuuayeoq4iv4k3zf5wdgh3@tocu6c7mj4lt/
> > [1]
> >
> > Signed-off-by: Breno Leitao <leitao@xxxxxxxxxx>
>
> ## Form letter - net-next-closed
>
> The net-next tree is closed for new drivers, features, code refactoring
> and optimizations due to the merge window and the winter break. We are
> currently accepting bug fixes only.
>
> Please repost when net-next reopens after Jan 2nd.
>
> RFC patches sent for review only are obviously welcome at any time.
> ---
> To save me a few moments, I will not send the same messages in reply to
> the others pending net-next patches of yours, but this still applies :-P

Shame on me! I haven't paid attention to the announcement emails. Fixed
it now.

Sorry for the noise,
--breno