From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 A9863374A14; Thu, 27 Aug 2026 12:59:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787835579; cv=none; b=pf8lrgeq6bLhekF9Za7EeCv2LAriuPbJru3GgFrqXWZs04hGIgWuzCEugxWaeWATtj8yUL90P6K8RxDOo3dMBQjPN7WzUdrPByiSUFBichbDZyF/EBG1v2QS1XG/3gFttl86vAQaomhZ/qRlDBAGIKA1sBgURgrWRDgLug0kXlc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787835579; c=relaxed/simple; bh=n4g67O2ahbEYQjmAR1A9xvd9Q4M5H24NCJnflkw+TVQ=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=Z9nfw703RmupiFCj/oHKZLb/rWE1fFuRMzUgadFUTO1RzkRJCdtow4O6QISD3xoJkArza/QAmmOm8a4wnMunWI30uewuz6xT09ImsMI/AVnA24p1ShAnZZT8vmO4Qfw9KWdyhY1GmDYl9aFQufJX4yW1iaF731Tp7y+yNgPXT6Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=Q6Np/Wdc; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=b+vOAjAR; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="Q6Np/Wdc"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="b+vOAjAR" From: John Ogness DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1787835566; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Ttq7Bkjlgdu0Zd+0ixn9ELU0etKIRWqFZqD1UHLmrgc=; b=Q6Np/WdcLDbTppRHdNIsZvsXbCV0VpGuqjeHIZskuxVG5gp/xViV56RHP/72Ps82a5j0/s 1s/gEQAnxzZSsMq/La7yHyH0z5nn5tzI4yyhYP8P9VBkTA6gUAQ7WJHLsad/NvJhRSwVS6 Jh4LrPZ/KRZxmetrSJgMJCPzgy8jD8leK/k3gLZm47eSFkIuvUnnUwjEw8SFbQP3Nw2wji 8DXoij2zHhNE/ikjGIZAXN8N1NWvbSNGbp2I3OT7Kx2SmjNuilEvGqXZy1+ydlCudCLtJx +CufXmP+B6Q33F1mmis+AGQPGF4kjpikugaRN3E8utw/DYHK2V+x+K2QvuKh7g== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1787835566; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Ttq7Bkjlgdu0Zd+0ixn9ELU0etKIRWqFZqD1UHLmrgc=; b=b+vOAjAR3tlzs71HRuvPRJL98R7RFTZxC81KnRjz15M3vLEBFLjfmN/ud4z7HbyHAXkWWH b0LhPwbuPhUw8CCA== To: Sebastian Andrzej Siewior , Petr Mladek , Jon Hunter Cc: Greg Kroah-Hartman , Jiri Slaby , Andy Shevchenko , linux-kernel@vger.kernel.org, Ilpo =?utf-8?Q?J=C3=A4rvinen?= , Andy Shevchenko , Hugo Villeneuve , Kees Cook , Stepan Ionichev , Xin Zhao , Osama Abdelkader , Fushuai Wang , Marco Felsch , linux-serial@vger.kernel.org, "linux-tegra@vger.kernel.org" Subject: Re: [PATCH tty v11 1/2] serial: 8250: Switch to nbcon console, take 2 In-Reply-To: <20260826075925.WTEVoXWi@linutronix.de> References: <877bll9d91.fsf@jogness.linutronix.de> <875x139eqr.fsf@jogness.linutronix.de> <6b46866f-548f-4963-bc41-48ce15ae9012@nvidia.com> <877ble714e.fsf@jogness.linutronix.de> <87pkz56epl.fsf@jogness.linutronix.de> <20260826075925.WTEVoXWi@linutronix.de> Date: Thu, 27 Aug 2026 15:05:25 +0206 Message-ID: <875x0vpvma.fsf@jogness.linutronix.de> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain Hi Jon, On 2026-08-26, Sebastian Andrzej Siewior wrote: > If that irq_work is the problem that making nbcon_irq_work LAZY should > delay it, masking the problem. Making nbcon_irq_work LAZY should work around this problem. And, actually, it should be fine to make nbcon_irq_work LAZY in general since it is only related to non-emergency messages, which are delayed anyway. Jon, could you run your tests with only the following patch applied? If this works for you, I will submit an official version of the patch. diff --git a/kernel/printk/nbcon.c b/kernel/printk/nbcon.c index a5921a84a80ed..ad79e30afd647 100644 --- a/kernel/printk/nbcon.c +++ b/kernel/printk/nbcon.c @@ -1782,7 +1782,7 @@ bool nbcon_alloc(struct console *con) } rcuwait_init(&con->rcuwait); - init_irq_work(&con->irq_work, nbcon_irq_work); + con->irq_work = IRQ_WORK_INIT_LAZY(nbcon_irq_work); atomic_long_set(&ACCESS_PRIVATE(con, nbcon_prev_seq), -1UL); nbcon_state_set(con, &state);