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Date: Wed, 8 Nov 2017 11:22:29 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Tejun Heo <tj@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Petr Mladek <pmladek@suse.com>, linux-kernel@vger.kernel.org,
        kernel-team@fb.com, Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 2/2] Subject: printk: Don't trap random context in
 infinite log_buf flush
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On Tue, 7 Nov 2017 05:23:50 -0800
Tejun Heo <tj@kernel.org> wrote:

> Hello, Sergey.
> 
> On Tue, Nov 07, 2017 at 11:04:34AM +0900, Sergey Senozhatsky wrote:
> > just to make sure. there is a typo in Steven's patch:
> > 
> > 	while (!READ_ONCE(console_waiter))
> > 
> > should be
> > 
> > 	while (READ_ONCE(console_waiter))
> > 
> > is this the "tweaking" you are talking about?  
> 
> Oh, I was talking about tweaking the repro, but I'm not sure the above
> would change anything. 

No, it would change an awful lot.

It would cause two printers to access the consoles at the same time,
which would lead to unpredictable behavior.

-- Steve