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Date: Tue, 17 May 2016 09:05:29 -0700
From: Tejun Heo <tj@kernel.org>
To: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Calvin Owens <calvinowens@fb.com>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
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        Geliang Tang <geliangtang@163.com>, Ivan Delalande <colona@arista.com>,
        linux-kernel@vger.kernel.org, kernel-team@fb.com
Subject: Re: [RFC][PATCH] printk: Add option to append kernel version to the
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On Wed, May 18, 2016 at 12:43:10AM +0900, Sergey Senozhatsky wrote:
> > Given that most of the messages are written minding typical console
> > widths, whether for editing or outputting, I don't think that's a
> > practical concern.  We're not talking about appending kilobytes worth
> > of additional information here.
> 
> hm, I'd probably agree. any chance printk(KERN_CONT) can cause any problems?
> for example,

Plain printk messages are capped at around 1k (LONG_LINE_MAX) while
extended messages can grow upto 8k in size.  Because extended messages
are escaped, plain message can theoretically be blown upto 4k but that
still leaves us with 4k buffer.  Direct extended messages can use more
but given that our only usages are for tagging some metadata, that's
only a theoretical possibility at this point.  So, I don't think we
have anything to worry about at this point.

Thanks.

-- 
tejun