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Date: Thu, 6 Apr 2017 19:33:06 +0200
From: Pavel Machek <pavel@ucw.cz>
To: Jan Kara <jack@suse.cz>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Ye Xiaolong <xiaolong.ye@intel.com>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
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        Jiri Slaby <jslaby@suse.com>, Len Brown <len.brown@intel.com>,
        linux-kernel@vger.kernel.org, lkp@01.org
Subject: Re: [printk]  fbc14616f4:
 BUG:kernel_reboot-without-warning_in_test_stage
Message-ID: <20170406173306.GD10363@amd>
References: <20170329092511.3958-9-sergey.senozhatsky@gmail.com>
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 <20170331023506.GB3493@jagdpanzerIV.localdomain>
 <20170331040438.GA366@jagdpanzerIV.localdomain>
 <20170331063913.GE20961@yexl-desktop>
 <20170331144730.GA10578@tigerII.localdomain>
 <87a881v52o.fsf@xmission.com>
 <20170403093152.GB15168@quack2.suse.cz>
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Hi!

> This patch set gives up part of the printk() reliability for bounded
> latency (at least unless we detect we are really in trouble) which is IMHO
> a good trade-off for lots of users (and others can just turn this feature
> off).

If they can ever realize they were bitten by this feature.

Can we go for different tradeoff?

In console_unlock(), if you detect too much work, print "Too many
messages to print, %d bytes delayed" and wake up kernel thread.

You still get the latency, and people bitten by this feature will at
least get fair warning.

									Pavel
--=20
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo=
g.html

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