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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <737d6c96a51b5975c9fd7ed302df014e0d5e4fe1.camel@suse.com>
Date: Wed, 07 Jan 2026 12:04:55 -0300
From: Marcos Paulo de Souza <mpdesouza@...e.com>
To: Breno Leitao <leitao@...ian.org>
Cc: Andrew Lunn <andrew+netdev@...n.ch>, "David S. Miller"
 <davem@...emloft.net>,  Eric Dumazet <edumazet@...gle.com>, Jakub Kicinski
 <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>, 
	netdev@...r.kernel.org, linux-kernel@...r.kernel.org, asantostc@...il.com, 
	efault@....de, gustavold@...il.com, calvin@...nvd.org, jv@...sburgh.net, 
	kernel-team@...a.com
Subject: Re: [PATCH net-next 2/2] netconsole: convert to NBCON console
 infrastructure

On Tue, 2026-01-06 at 07:43 -0800, Breno Leitao wrote:
> Hello Marcos,
> 
> On Fri, Jan 02, 2026 at 12:54:14AM -0300, Marcos Paulo de Souza
> wrote:
> > On Mon, 22 Dec 2025 06:52:11 -0800 Breno Leitao <leitao@...ian.org>
> > wrote:
> > > +		if (!nbcon_enter_unsafe(wctxt))
> > > +			continue;
> > 
> > In this case, I believe that it should return directly? If it can't
> > enter in the
> > unsafe region the output buffer is not reliable anymore, so
> > retrying the send
> > the buffer to a different target isn't correct anymore. Petr, John,
> > do you
> > agree?
> 
> That makes sense. I undersatnd that the ownership will not be
> re-acquired here by just looping through the netconsole targets,
> right?

Yes, take a look into the drivers/tty/serial/*, some of the only
reacquire the context to reset some hardware registers, since the
printing context was lost. In this case, for you, I don't believe that
you can't continue trying to send data to other targets, since the
original data is gone.

In any case, the context reacquire method is nbcon_reacquire_nobuf.