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From: John Dyson <dyson@dyson.iquest.net>
Message-Id: <199701212129.QAA08929@dyson.iquest.net>
Subject: Re: VM bogon? Was: Re: NIS breakage
To: mark@grondar.za (Mark Murray)
Date: Tue, 21 Jan 1997 16:29:54 -0500 (EST)
Cc: bde@zeta.org.au, syssgm@devetir.qld.gov.au, freebsd-current@freebsd.org
In-Reply-To: <199701211947.VAA05914@grackle.grondar.za> from "Mark Murray" at Jan 21, 97 09:47:27 pm
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> 
> Bruce Evans wrote:
> > I duplicated the problem on a 486 configured as a 386.  I used the enclosed
> > program to force other processes out to swap (run /usr/bin/vi, then memhog,
> > then check that vi has an RSS of 0, then hit a key in vi.  vi always gets
> > EFAULT for reading a 255-buye buffer).
> 
> I did it here (with Stephen's patch), and I still get the bug in vi.
> The various YP bits (in particular portmap) seem pretty stable.
> 
> [ The only problem I see in YP (And it is almost certainly not related to
> VM) is that I get "rpc.ypxfr timeout"'s whenever I try to push the
> maps from the 386 onto my Old-Faithful 486dx. (The timeouts happen
> on the 486). I'll report on this in detail in another message ]
> 
> > The bug probably also occurs in suword(), susword() and subyte().
> > 
> > susword() and susword() are also buggy on 386's if the [s]word crosses a
> > page boundary.
> 
> Could this be the problem I am seeing with vi and not with portmap?
> 
> > /* memhog.c */
> 
> Thanks! This utility is a bit of a bastard to systems ;-)
> 
I am going to check these changes and commit them tonight...  Looks
like you guys have found a serious problem with the 386 code.

John