Messages in this thread | | | Date | Thu, 07 Oct 2010 16:29:23 +0100 | From | "Jan Beulich" <> | Subject | Re: patch disabling use of PSE on Atom CPUs with a certain erratum |
| |
>>> On 07.10.10 at 17:10, "H. Peter Anvin" <hpa@zytor.com> wrote: > On 10/07/2010 07:52 AM, Jan Beulich wrote: >>>>> On 07.10.10 at 16:08, "H. Peter Anvin" <hpa@zytor.com> wrote: >>> On 10/07/2010 07:01 AM, Jan Beulich wrote: >>>>> >>>>> Those Atoms don't have 64-bit support. >>>> >>>> That's different from what I found looking around on the web. >>>> >>> >>> Do tell... >> >> E.g. >> >> http://en.wikipedia.org/wiki/List_of_Intel_Atom_microprocessors >> >> in particular the Atom 230 and Atom 330 (which to my reading match >> the spec updates for the 200 and 300 series, which in turn exhibit >> the erratum in question). >> > > You're right... I misremembered. The question is what to do at this > point, since we're already in trouble. A possible failure on startup > seems better than a state in which we could get data corruption at > almost any time.
The only possible (afaict) way to address this would be to check for the erratum in the boot code, and establish 4k page mappings from the beginning. That's likely going to be ugly though.
The main reason I was asking was not so much to trigger a code change, but to understand the implications (since both the comment in the code and the changeset comment don't really hint at this leaving a problem open for 64-bit), to some degree to understand whether e.g. Xen would also need such a workaround (if anyone cares to run Xen on Atoms).
Jan
| |