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Date: Wed, 5 Jun 2024 12:14:56 +0200
From: Petr Mladek <pmladek@suse.com>
To: Juri Lelli <juri.lelli@redhat.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>,
	Steven Rostedt <rostedt@goodmis.org>, linux-kernel@vger.kernel.org,
	John Ogness <john.ogness@linutronix.de>
Subject: Re: [PATCH linux-next] printk: nbcon: Fix
 nbcon_cpu_emergency_flush() when preemptible
Message-ID: <ZmA6oGrO1YVF-IYj@pathway.suse.cz>
References: <87zfrzvhsp.fsf@jogness.linutronix.de>
 <ZmA5oIkImclKM0vx@pathway.suse.cz>
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On Wed 2024-06-05 12:10:50, Petr Mladek wrote:
> On Wed 2024-06-05 11:57:34, John Ogness wrote:
> > nbcon_cpu_emergency_flush() can be called in a preemptible
> > context. In that case the CPU is not in an emergency state.
> > However, in order to see that the CPU is not in an emergency
> > state (accessing the per-cpu variable), preemption must be
> > disabled.
> > 
> > Disable preemption when checking the CPU state.
> > 
> > Reported-by: Juri Lelli <juri.lelli@redhat.com>
> > Closes: https://lore.kernel.org/aqkcpca4vgadxc3yzcu74xwq3grslj5m43f3eb5fcs23yo2gy4@gcsnqcts5tos
> > Fixes: 46a1379208b7 ("printk: nbcon: Implement emergency sections")
> > Signed-off-by: John Ogness <john.ogness@linutronix.de>
> 
> Great catch!
> 
> Reviewed-by: Petr Mladek <pmladek@suse.com>
> 
> I am going to push it...

Juri, should/could I add your Tested-by ?

Best Regards,
Petr