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Piccoli" , Lukas Wunner , Arnd Bergmann Subject: Re: [PATCH printk v2 18/26] printk: nbcon: Add unsafe flushing on panic Message-ID: References: <20240218185726.1994771-1-john.ogness@linutronix.de> <20240218185726.1994771-19-john.ogness@linutronix.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240218185726.1994771-19-john.ogness@linutronix.de> On Sun 2024-02-18 20:03:18, John Ogness wrote: > Add nbcon_atomic_flush_unsafe() to flush all nbcon consoles > using the write_atomic() callback and allowing unsafe hostile > takeovers. Call this at the end of panic() as a final attempt > to flush any pending messages. > > Note that legacy consoles use unsafe methods for flushing > from the beginning of panic (see bust_spinlocks()). Therefore, > systems using both legacy and nbcon consoles may still fail to > see panic messages due to unsafe legacy console usage. > > Signed-off-by: John Ogness Reviewed-by: Petr Mladek Best Regards, Petr