cvs commit: src/sys/boot/i386/cdboot cdboot.s

John Baldwin jhb at
Wed Apr 12 15:12:17 UTC 2006

On Wednesday 12 April 2006 11:00, Alexander Leidinger wrote:
> John Baldwin <jhb at> wrote:
> > On Tuesday 11 April 2006 23:40, Maxim Sobolev wrote:
> >> BTW, can you please take a look at the problem with SMP bootstrap on
> >> Aplintel notebooks? For some reason our SMP kernel can't start the
> >> second processor. You can find more details here:
> >>
> >>
> >
> > I looked but unfortunately there isn't much to go on.  We follow the sequence
> > Intel specifies.  If you want to debug this you'll have to probably do
> > something like bring back the postcode stuff in mp startup and dump the
> > various postcode values to see how far the AP got, etc.
> If it helps: I've read somewhere that the dual-core CPUs from Intel  
> changed the semantic of the HT <something> (don't remember if it's the  
> feature bit or the register or whatever... I don't have that much  
> low-level knowledge of current CPUs). They made this so that Windows  
> XP is able to run with the dual-core CPU instead of requiring the  
> Professional version to use both CPU cores.
> So maybe we need to change the part in FreeBSD which handles the HT  
> part of the CPU...

Unless the APIC ID in the MADT is wrong and WinXP is not using the
MADT but some other method to determine the APIC ID of core's, this
shouldn't matter.

John Baldwin <jhb at>  <><
"Power Users Use the Power to Serve"  =

More information about the cvs-src mailing list