From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from stravinsky.debian.org (stravinsky.debian.org [82.195.75.108]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 379FE361DC1; Fri, 6 Feb 2026 12:11:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=82.195.75.108 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770379878; cv=none; b=udxREC8WpTtWF2ZzxyzYemJKBoFixvT2yy0QccHHnRdoV5ywiu1USb9LVEE85bqlLS3H+nyuesbyafdoNGwd1MuMPVbWmztwQ0/0TeNyRoeSoobgWUvzVQf3BBFruC5hx9pIqvgG9dvI9UxWFePGslKRls/2ei6Ez1BlrZOppac= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770379878; c=relaxed/simple; bh=singIeLIaxBOhho6/qJo5E+oQFqvt7GzcQiJv4BX/a0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=qJVkC7TftDa2hBzTujguIVwPj7ii6zTTZa/lPmpISJVelVEwE3aGW/CSfZjoX8hejBy89uF+gtxBmgIwC6cDdCQ+KgOSI1Mv6MaebxV5mVNYFInaANT8hnwstQzUTmBDq0EwQsiwZtgo4RsDUPVzfFb2zpnK+dh+2Y1pNF4HRY0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=debian.org; spf=none smtp.mailfrom=debian.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b=BdRdhxly; arc=none smtp.client-ip=82.195.75.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=debian.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=debian.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b="BdRdhxly" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=debian.org; s=smtpauto.stravinsky; h=X-Debian-User:In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=17CApZ0SXsDocYCoDQD0Gmc7fTR3XjxqZI9nCOlKYTs=; b=BdRdhxly2pfDgcLk4ldPHLlKoZ QufkOshxgDhDBB1Tus0Zc7xhItQ0bXmnOg7gFLs89NcReKXA+MAEYYjXnuB8SVC78LhOFuGo7IVDp 0Z9ICFQ33qJZx0p7l2T+EtT1RDKixRRk7+XQw6eq6LD9UQter6Dz8WcYY23Um5iRCErUGW9Kkgs/b q3+jkyipvWSr0X0Kfhau1tUyXtx+djPDHf0lWJfuD2gnRHBrr9beqvhmmT4na8FoLVyxbo6gBgJko FX81GvQ/OAuxDLpy10PapniLf7dU59JSHUNx2PJ2lf+tRGeEg+GUs46yW9F3v+aeSWsQJsaaQcGoA j7+HZwLg==; Received: from authenticated user by stravinsky.debian.org with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94.2) (envelope-from ) id 1voKfn-0079It-AJ; Fri, 06 Feb 2026 12:10:55 +0000 Date: Fri, 6 Feb 2026 04:10:49 -0800 From: Breno Leitao To: John Ogness Cc: Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , pmladek@suse.com, Greg Kroah-Hartman , Steven Rostedt , Sergey Senozhatsky , Andrew Morton , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, asantostc@gmail.com, efault@gmx.de, gustavold@gmail.com, calvin@wbinvd.org, jv@jvosburgh.net, mpdesouza@suse.com, kernel-team@meta.com, Simon Horman Subject: Re: [PATCH net-next v6 0/4] net: netconsole: convert to NBCON console infrastructure Message-ID: References: <20260203-nbcon-v6-0-985f3bdb3267@debian.org> <87fr7gp0qb.fsf@jogness.linutronix.de> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87fr7gp0qb.fsf@jogness.linutronix.de> X-Debian-User: leitao On Thu, Feb 05, 2026 at 12:12:52AM +0106, John Ogness wrote: > On 2026-02-03, 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: > > > > 0) Extend printk to expose CPU and taskname (task->comm) where the > > printk originated from. (Thanks John and Petr for the support in > > getting this done) > > 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. > > > > Netdev maintainers, Petr suggested that this patchset goes through netdev[2] > > > > Link: https://lore.kernel.org/all/b2qps3uywhmjaym4mht2wpxul4yqtuuayeoq4iv4k3zf5wdgh3@tocu6c7mj4lt/ [1] > > Link: https://lore.kernel.org/all/aW9D5M0o9_8hdVvt@pathway.suse.cz/ [2] > > > > Signed-off-by: Breno Leitao > > > > --- > > Changes in v6: > > - Do not select PRINTK_EXECUTION_CTX in NETCONSOLE_DYNAMIC (Jakub) > > - Do not make PRINTK_EXECUTION_CTX user visible (Jakub) > > I am really sorry, but I failed to communicate what I meant about > introducing the CONSOLE_HAS_EXECUTION_CTX symbol. > > As Jakub mentioned, NETCONSOLE_DYNAMIC should just directly select > PRINTK_EXECUTION_CTX and get rid of the CONSOLE_HAS_EXECUTION_CTX symbol > (like you had in v1). Ack! Let me update it. Thanks for the clarification, --breno