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Date:   Tue, 28 May 2019 15:49:58 +0200
From:   Petr Mladek <pmladek@suse.com>
To:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc:     Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Dmitry Safonov <dima@arista.com>, linux-kernel@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jslaby@suse.com>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linus Togyrvalds <torvalds@linux-foundation.org>
Subject: Re: [RFC] printk/sysrq: Don't play with console_loglevel
Message-ID: <20190528134958.kpo5voy2jzmw57dw@pathway.suse.cz>
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On Tue 2019-05-28 19:15:43, Tetsuo Handa wrote:
> On 2019/05/28 17:51, Sergey Senozhatsky wrote:
> >> You are trying to omit passing KERN_UNSUPPRESSED by utilizing implicit printk
> >> context information. But doesn't such attempt resemble find_printk_buffer() ?
> > 
> > Adding KERN_UNSUPPRESSED to all printks down the op_p->handler()
> > line is hardly possible. At the same time I'd really prefer not
> > to have buffering for sysrq.
> 
> I don't think it is hardly possible. And I really prefer having
> deferred printing for SysRq.

This thread is about problems with manipulating console_loglevel.

"Deferred printk" is another very complicated and controversial
problem. Please, discuss it in a separate thread.

Thanks in advance.

Best Regards,
Petr Mladek