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Date: Tue, 24 Dec 2013 11:50:32 +0900
From: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
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To: Kay Sievers <kay@vrfy.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Eiichi Tsukata <eiichi.tsukata.xh@hitachi.com>,
        Frederic Weisbecker <fweisbec@gmail.com>, Tejun Heo <tj@kernel.org>,
        yrl.pp-manager.tt@hitachi.com,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Joe Perches <joe@perches.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Subject: Re: Re: [PATCH 0/2] [BUGFIX] printk: Fix message continuation
 breakage involved with structured printk
References: <20131220094134.24233.2969.stgit@yunodevel> <CAPXgP11H7EB5Sfezf_7NkKzXT4n4EnPPyE2wWV9YQmR=3LsbAw@mail.gmail.com>
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Hi Kay,

Thank you for replying me.

(2013/12/20 20:29), Kay Sievers wrote:
> On Fri, Dec 20, 2013 at 10:41 AM, Yoshihiro YUNOMAE
> <yoshihiro.yunomae.ez@hitachi.com> wrote:
>
>> This patch set fixes message continuation breakage involved with structured
>> printk. A SCSI driver may output two continuation error messages like
>>      scmd_printk("foo");
>>      printf("bar\n");
>
> Which is the absolutely wrong thing to do. Structured logging and racy
> printk continuation must never be mixed. Userspace needs to be sure
> that dictionary entries are not subject to racy continuation hackery,
> and that these mwssages atomic, whole and intact.

I see.
As you say, user tools need to support messages output in multiple lines
for SMP environments even if this patch set is introduced.

> Please do not mix the both and do not apply these patches.

OK, I'll make important messages with KERN_CONT or no-prefix printk()
output those in single line.

Thanks,
Yoshihiro YUNOMAE

-- 
Yoshihiro YUNOMAE
Software Platform Research Dept. Linux Technology Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: yoshihiro.yunomae.ez@hitachi.com