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Date: Mon, 12 Dec 2016 16:20:44 +0100
From: Petr Mladek <pmladek@suse.com>
To: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Jan Kara <jack@suse.cz>,
        Tejun Heo <tj@kernel.org>, Calvin Owens <calvinowens@fb.com>,
        Thomas Gleixner <tglx@linutronix.de>,
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        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Subject: Re: [RFC][PATCHv5 4/7] printk: always use deferred printk when flush
 printk_safe lines
Message-ID: <20161212152043.GC2441@pathway.suse.cz>
References: <20161201135546.15549-1-sergey.senozhatsky@gmail.com>
 <20161201135546.15549-5-sergey.senozhatsky@gmail.com>
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On Thu 2016-12-01 22:55:43, Sergey Senozhatsky wrote:
> Always use printk_deferred() in printk_safe_flush_line().
> Flushing can be done from NMI or printk_safe contexts (when
> we are in panic), so we can't call console drivers, yet still
> want to store the messages in the logbuf buffer. Therefore we
> use a deferred printk version.

Also this makes it clear that we are storing the messages into
the main logbuffer here. Note that printk() might get redirected
to the per-CPU buffer when this is triggered in panic.

> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
> Suggested-by: Petr Mladek <pmladek@suse.com>

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

Best Regards,
Petr