From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BD9E6C4332F for ; Thu, 10 Nov 2022 14:19:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230096AbiKJOTI (ORCPT ); Thu, 10 Nov 2022 09:19:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51412 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229528AbiKJOTF (ORCPT ); Thu, 10 Nov 2022 09:19:05 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A9871165AF for ; Thu, 10 Nov 2022 06:19:04 -0800 (PST) From: John Ogness DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1668089943; 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=CLHBQggQls4mWIgeZbw7Mj4Foog8Zgpi+AZP3I0LDjo=; b=TeyzoeMBsyYpwQEcZ7EWDcxKdM1GA5YG3rA9Rd/s6Mj/hMRJt/CpMZqEY2AONXSU5QtyvO PXdvYEzwGP3Ulb+OiWg35ZaYuNuAI3CHWUqqEPfBQLNfvmOQ/ZXjJImfXkGx7uy0XfTQWA vmtCMPHTIqnf8FO54hbFouDBVPzGZ69l2EBCngFRZNG9G1I2tpXDMAO1QHwU968mx4yzod HXi5s97LggtkkmtA56Lwre1sjoZRcHFgJVMPKk8B1dzPVlGI31nSoS8gV3GOhutszYS7WC tFXYCVanN6ah4JTrlmFUNPzD2QkKPYd2rL2q+btcRzXBjjzUkvooQ2dN6jXKPQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1668089943; 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=CLHBQggQls4mWIgeZbw7Mj4Foog8Zgpi+AZP3I0LDjo=; b=XVCMkXBronBmd1KX+rOaAL7HrZZrturZw18aI93S+jm3mmMSItyqIEZXc2Qx33a+nZGgqy nib2Diw68mRskRAg== To: Petr Mladek Cc: Sergey Senozhatsky , Steven Rostedt , Thomas Gleixner , linux-kernel@vger.kernel.org, Geert Uytterhoeven , linux-m68k@lists.linux-m68k.org Subject: Re: [PATCH printk v3 24/40] tty: nfcon: use console_is_registered() In-Reply-To: References: <20221107141638.3790965-1-john.ogness@linutronix.de> <20221107141638.3790965-25-john.ogness@linutronix.de> Date: Thu, 10 Nov 2022 15:25:02 +0106 Message-ID: <87cz9u6gfd.fsf@jogness.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022-11-10, Petr Mladek wrote: >> diff --git a/arch/m68k/emu/nfcon.c b/arch/m68k/emu/nfcon.c >> index 557d60867f98..292669fa480f 100644 >> --- a/arch/m68k/emu/nfcon.c >> +++ b/arch/m68k/emu/nfcon.c >> @@ -49,14 +49,14 @@ static void nfcon_write(struct console *con, const char *str, >> static struct tty_driver *nfcon_device(struct console *con, int *index) >> { >> *index = 0; >> - return (con->flags & CON_ENABLED) ? nfcon_tty_driver : NULL; >> + return console_is_registered(con) ? nfcon_tty_driver : NULL; >> } >> >> static struct console nf_console = { >> .name = "nfcon", >> .write = nfcon_write, >> .device = nfcon_device, >> - .flags = CON_PRINTBUFFER, >> + .flags = CON_PRINTBUFFER | CON_ENABLED, > > This causes that register_console() will always put the console into > console_list. It causes regression, see below. Agreed. Nice catch. I will remove initializing with CON_ENABLED. >> .index = -1, >> }; >> >> @@ -106,10 +106,8 @@ static int __init nf_debug_setup(char *arg) >> return 0; >> >> stderr_id = nf_get_id("NF_STDERR"); >> - if (stderr_id) { >> - nf_console.flags |= CON_ENABLED; >> + if (stderr_id) >> register_console(&nf_console); > > My understanding is that this should enable the console > when debug=nfcon kernel parameter is used. > > It is a non-standard way. This is why CON_ENABLED flag > has to be explicitly set. Understood. I will add a comment explaining why CON_ENABLED is set here. >> - } >> >> return 0; >> } >> @@ -151,7 +149,7 @@ static int __init nfcon_init(void) >> >> nfcon_tty_driver = driver; >> >> - if (!(nf_console.flags & CON_ENABLED)) >> + if (!console_is_registered(&nf_console)) >> register_console(&nf_console); > > This calls register_console() when it was not already > registered by the debug=nfcon early parameter. > > It is the standard way. It should enable the console only > when console=nfcon is defined on the commandline. Or when > there is no preferred console and no console enabled by default yet. > > We should not pre-set CON_ENABLED in this case. Agreed. The hunk itself is OK. John