Mikael Pettersson wrote: > On Sun, 04 Nov 2007 11:41:58 -0800, H. Peter Anvin wrote: > >> Mikael Pettersson wrote: >> >>> First patch didn't build. Second patch builds and boots Ok. >>> >>> So this means the 486 DX4 has a buggy mov to %cr0? >>> >>> >> Apparently. >> > > Maybe not. I had a look in Intel's SDM Vol3, and the > section "switching to protected mode" specifies that > a move to %cr0 that sets PE should immediately be > followed by a far jmp or call. >
Yes, that's what the spec says. I queried this a few months ago, but hpa used his convincing voice and said that in practice it isn't necessary; there are no known cpus which need this, and any that do would cause other things to break. But I guess now we have the counter-example... J - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/