Re: Re: [PATCH 0/2] [BUGFIX] printk: Fix message continuationbreakage involved with structured printk

From: Yoshihiro YUNOMAE
Date: Mon Dec 23 2013 - 21:50:42 EST


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@xxxxxxxxxxx> 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@xxxxxxxxxxx


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