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Date: Tue, 19 Jul 2016 23:55:09 +0900
From: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
To: James Bottomley <James.Bottomley@HansenPartnership.com>
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Cc: Jiri Kosina <jkosina@suse.com>, ksummit-discuss@lists.linuxfoundation.org,
	Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>,
	Viresh Kumar <viresh.kumar@linaro.org>, Tejun Heo <tj@kernel.org>
Subject: Re: [Ksummit-discuss] [TECH TOPIC] asynchronous printk
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Hello,

On (07/19/16 07:45), James Bottomley wrote:
> On Tue, 2016-07-19 at 12:47 +0900, Sergey Senozhatsky wrote:
> > Hello,
> > 
> > Wondering if anyone will be interested in printk-related topics
> > (or we can handle it in the mailing list).
> > 
> > What I have on my list is:
> 
> Are there any bug reports for these cases?  If there are, I'd use the
> bug report as an opportunity to fix on the relevant list and if there
> aren't, I'd say that the problem is then largely theoretical and
> there's not much point solving it until it becomes a real problem.

yes, there are reports. for instance,
http://marc.info/?l=linux-kernel&m=146823278316663

I do have same problems with pintk (lockups, stalls, etc.)
and even more.


> For instance on the KERN_CONT we've been debating the problems of pre
> -empt and continuation lines for years but no-ones cared enough to fix
> it.  This means either the problem isn't seen often enough in the field
> or that when it is seen there hasn't been much difficulty disentangling
> the log.  For the former, there's no need to fix something that isn't
> seen in practice and for the latter, if no-one cares enough then it's
> not a big enough problem to fix.

well, I agree that it doesn't make it impossible to read the logs.
how often does it happen... on my laptop sometimes KERN_CONT lines
are not always really continuous. so I observe it, in some sense.

	-ss