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Newsgroups: comp.os.386bsd.bugs Path: sserve!newshost.anu.edu.au!munnari.oz.au!constellation!osuunx.ucc.okstate.edu!moe.ksu.ksu.edu!hobbes.physics.uiowa.edu!math.ohio-state.edu!cs.utexas.edu!uunet!emba-news.uvm.edu!trantor.emba.uvm.edu!wollman From: wollman@trantor.emba.uvm.edu (Garrett Wollman) Subject: Re: kernel writes to user space (was Re: Nethack) Message-ID: <1993Jun30.022629.24466@uvm.edu> Sender: news@uvm.edu Organization: University of Vermont, EMBA Computer Facility References: <20bfrm$le7@pdq.coe.montana.edu> <C990xF.43n@sneaky.lonestar.org> <1993Jun29.181749.5833@fcom.cc.utah.edu> <20qqgu$dj@werple.apana.org.au> Date: Wed, 30 Jun 1993 02:26:29 GMT Lines: 18 In article <20qqgu$dj@werple.apana.org.au> andrew@werple.apana.org.au (Andrew Herbert) writes: >Exactly - these copy-on-write (actually read-only, as Terry says) protection >faults are not generated for data copied into user space by copyout() on the >i386, *nor* is it being handled manually by the copyout() routine. Isn't there a flag bit you can turn on on a *4*86, which tells the MMU to behave in a sane manner? If so, then perhaps someone ought to write code to take advantage of this, triggered by defined(i486) && !defined(i386). (That's probably why NeXTStep doesn't run on a 386...) -GAWollman -- Garrett A. Wollman | Shashish is simple, it's discreet, it's brief. ... wollman@emba.uvm.edu | Shashish is the bonding of hearts in spite of distance. uvm-gen!wollman | It is a bond more powerful than absence. We like people UVM disagrees. | who like Shashish. - Claude McKenzie + Florent Vollant