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Date:   Wed, 20 Apr 2022 15:55:22 +0200
From:   Petr Mladek <pmladek@suse.com>
To:     John Ogness <john.ogness@linutronix.de>
Cc:     Sergey Senozhatsky <senozhatsky@chromium.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH printk v3 05/15] printk: wake waiters for safe and NMI
 contexts
Message-ID: <YmAQyvPEwy5XaKWl@alley>
References: <20220419234637.357112-1-john.ogness@linutronix.de>
 <20220419234637.357112-6-john.ogness@linutronix.de>
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On Wed 2022-04-20 01:52:27, John Ogness wrote:
> When printk() is called from safe or NMI contexts, it will directly
> store the record (vprintk_store()) and then defer the console output.
> However, defer_console_output() only causes console printing and does
> not wake any waiters of new records.
> 
> Wake waiters from defer_console_output() so that they also are aware
> of the new records from safe and NMI contexts.
> 
> Fixes: 03fc7f9c99c1 ("printk/nmi: Prevent deadlock when accessing the main log buffer in NMI")
> Signed-off-by: John Ogness <john.ogness@linutronix.de>

Another great catch!

Reviewed-by: Petr Mladek <pmladek@suse.com>

Best Regards,
Petr