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Date:   Mon, 16 Apr 2018 15:38:16 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Sasha Levin <Alexander.Levin@microsoft.com>,
        Pavel Machek <pavel@ucw.cz>, Petr Mladek <pmladek@suse.com>,
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        Johannes Weiner <hannes@cmpxchg.org>,
        Mel Gorman <mgorman@suse.de>, Michal Hocko <mhocko@kernel.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Peter Zijlstra <peterz@infradead.org>, Jan Kara <jack@suse.cz>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        Byungchul Park <byungchul.park@lge.com>,
        Tejun Heo <tj@kernel.org>, Greg KH <gregkh@linuxfoundation.org>
Subject: Re: [PATCH AUTOSEL for 4.14 015/161] printk: Add console owner and
 waiter logic to load balance console writes
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On Mon, 16 Apr 2018 12:28:21 -0700
Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Mon, Apr 16, 2018 at 12:24 PM, Steven Rostedt <rostedt@goodmis.org> wrote:
> >
> > Right, but the fix to the API was also trivial. I don't understand why
> > you are arguing with me. I agree with you. I'm talking about this
> > specific instance. Where a bug was fixed, and the API breakage was
> > another fix that needed to be backported.  
> 
> Fair enough. Were you there when the report of breakage came in?

No I wasn't.

> 
> Because *my* argument is that reverting something that causes problems
> is simply *never* the wrong answer.
> 
> If you know of the fix, fine. But clearly people DID NOT KNOW. So
> reverting was the right choice.

But I don't see in the git history that this was ever reverted. My reply
saying that "I hope it wasn't reverted", was a response for it being
reverted in stable, not mainline.  Considering that the original bug
would allow userspace to write zeros anywhere in memory, I would have
definitely worked on finding why the API breakage happened and fixing
it properly before putting such a large hole back into the kernel.

I'm assuming that may have been what happened because the commit was
never reverted in your tree, and if I was responsible for that code, I
would be up all night looking for an API fix to make sure the original
fix isn't reverted.

-- Steve