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Date: Thu, 2 Feb 2017 17:13:27 +0100
From: Petr Mladek <pmladek@suse.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Andy Lutomirski <luto@kernel.org>,
        Peter Hurley <peter@hurleysoftware.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCHv7 5/8] printk: report lost messages in printk safe/nmi
 contexts
Message-ID: <20170202161327.GH23754@pathway.suse.cz>
References: <20161227141611.940-1-sergey.senozhatsky@gmail.com>
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On Thu 2017-02-02 09:34:09, Steven Rostedt wrote:
> On Thu, 2 Feb 2017 11:02:57 +0900
> Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> wrote:
> 
> > On (02/01/17 11:37), Steven Rostedt wrote:
> > > This looks fine, but I'm curious if you tested it. That is, added a
> > > bunch of printks to overflow the buffer. IIRC, I did it to the original
> > > nmi code. If you haven't you may want to just to make sure it works. I
> > > can also test it too if I get some time.  

I have tested it and actually found a bug. I was lucky because it was
a cornercase. It is already fixed upstream by the commit
4a998e322abc935e ("printk/NMI: fix up handling of the full nmi
log buffer").

> Please note how you tested it in your change log. It's not really a
> requirement, and you don't really have to do it. But it helps people
> have warm fuzzies about the code. I'm trying to do this in the future
> in my own work too.

Goot to know.

Best Regards,
Petr