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Date:      Tue, 18 Nov 1997 06:39:21 +0000 (GMT)
From:      homey <hometeam@techpower.net>
To:        KATO Takenori <kato@migmatite.eps.nagoya-u.ac.jp>
Cc:        Pierre.Beyssac@hsc.fr, freebsd-security@freebsd.org
Subject:   Re: now a Cyrix processor bug
Message-ID:  <Pine.BSF.3.96.971118063630.9708A-100000@techpower.net>
In-Reply-To: <199711181030.TAA06758@gneiss.eps.nagoya-u.ac.jp>

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Would this be added to the config file in the kernel or can this be added
to rc.local also?
CPU_CYRIX_NO_LOCK 

Also is there any info on the options for cyrix in freebsd?

hometeam@techpower.net
--We cannot all be masters, nor all masters 
   Cannot be truly follow'd--  

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On Tue, 18 Nov 1997, KATO Takenori wrote:

> > Has anynone seen this?
> > 
> > There seems to be a bug on the Cyrix, similar but not identical
> > to the Pentium's. However the workaround on the Cyrix is apparently
> > much simpler (you only need to disable LOCK mode in the CCR, if I
> > understood the fix right).
> 
> 3.0-current and RELENG_2_2 (including 2.2.5) have following option:
> 
> 	CPU_CYRIX_NO_LOCK
> 
> which enables weak locking.  Because I didn't know of the Coma bug,
> and recomended setting of NO_LOCK bit is 0 in the BIOS writer's guide, 
> NO_LOCK bit is not modified when above option is not set.  Because SMP 
> of FreeBSD doesn't support non-Intel chipsets, CPU_CYRIX_NO_LOCK
> options may have no harmful effect.
> 
> Also, another fix via special registers is propsed.  But, Cyrix
> doesn't disclose the meanings of such registers.  When Cyrix discloses 
> the meaning of registers, I will implement latter fix.
> 
> ----
> KATO Takenori <kato@ganko.eps.nagoya-u.ac.jp>
> Dept. Earth Planet. Sci., Nagoya Univ.,  Nagoya, 464-01, Japan
> PGP public key: finger kato@eclogite.eps.nagoya-u.ac.jp
> ------------------- Powered by FreeBSD(98) -------------------
> 




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