From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <46cfce6c709a9e19a483d5ae5445ab87@terzarima.net> To: 9fans@cse.psu.edu Subject: Re: [9fans] ok, *init* is running on ts7200 From: Charles Forsyth Date: Fri, 18 Mar 2005 16:30:33 +0000 In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Topicbox-Message-UUID: 26328c74-ead0-11e9-9d60-3106f5b1d025 >>Oh my goodness that's stupid. I wonder why they did that? it's certainly annoying. for x86 fans (and those processors often need big fans) i should explain that at least real mode in the powerpc, which sets you back to the instruction before you enabled vm, isn't as bad as `real' mode on the x86, which sets you back about 25 years. the powerpc at least is much the same processor but with VM switched off (but you've got to jump through a few hoops to put it on again). one popular way to switch the mmu back on is to do a return-from-interrupt back into the trap handler, having saved the state. one reason is that just setting the appropriate bits in the MSR might cause trouble (or might not). either way, to save the state you've got to address the appropriate kernel save area. are those memory accesses cached in that state? well ... it depends.