Re: 2.1.63 - testing Pentium bug workaround..

Alan Cox (alan@lxorguk.ukuu.org.uk)
Thu, 13 Nov 1997 23:59:11 +0000 (GMT)


> No, mul/div can't be locked. There aren't all that many instructions that
> can, and I personally think that the cmpxchg8b thing is the only one that
> shows _this_ particular problem. There might be other bugs out there,

Looking at other errata cmpxchg8b is also obviously "magic" because it
has another errata when storing the 8 bytes split across a page boundary
which as it happens isnt a bad one. The only other 8 byte stores appear
to be FPU and MMX - neither of which you can lock