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Message-ID: <f1eb20d1-6762-dc82-058a-cf27936bc0c6@infradead.org>
Date:   Sat, 18 Jun 2022 17:30:44 -0700
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Subject: Re: [PATCH] printk: allow direct console printing to be enabled
 always
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To:     "Jason A. Donenfeld" <Jason@zx2c4.com>,
        John Ogness <john.ogness@linutronix.de>,
        Petr Mladek <pmladek@suse.com>, Marco Elver <elver@google.com>,
        linux-kernel@vger.kernel.org
References: <YqyDqMAPHIxjA/xZ@zx2c4.com>
 <20220617133847.27517-1-Jason@zx2c4.com>
From:   Randy Dunlap <rdunlap@infradead.org>
In-Reply-To: <20220617133847.27517-1-Jason@zx2c4.com>
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On 6/17/22 06:38, Jason A. Donenfeld wrote:
> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index 8090130b544b..a960c47a2002 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -4389,6 +4389,14 @@
>  	printk.time=	Show timing data prefixed to each printk message line
>  			Format: <bool>  (1/Y/y=enable, 0/N/n=disable)
>  
> +	printk.always_direct=
> +			Rather than using kthreads for printk output, always
> +			write to the console immediately. This has performance
> +			implications, but will result in a more faithful
> +			ordering and interleaving with other processes writing
> +			to the console.
> +			Format: <bool>  (1/Y/y=enable, 0/N/n=disable)

or:

+			Format: <bool>  (1/Y/y/T/t/on=enable, 0/N/n/F/f/off=disable)

-- 
~Randy