[PATCH] bug in bigsmp CPU bringup

[Pallipadi, Venkatesh]

There is an bug in bigsmp sub-architecture, due to which it will not
enable all the CPUs when the BIOS-APICIDs are not 0 to n-1 (where n is
total number of CPUs). Particularly, only 2 CPU comes up on a system
that has 4 CPUs with BIOS APICID as (0, 1, 6, 7). 

The bug is root caused to check_apicid_present(bit) call in smpboot.c,
when bigsmp is expecting apicid in place of bit.
check_apicid_present(bit) in bigsmp subarchitecture checks the bit with
phys_id_present_map (which is actually map representing all apicids and
not bit).

One solution is to change check_apicid_present(bit) to
check_apicid_present(apicid), in smp_boot_cpus(). But, it can affect all
the other subarchitectures in various subtle ways. So, here is a simple
alternate fix (Thanks to Martin Bligh), which solves the above problem.

Please consider for inclusion in 2.6 base.

Thanks,
Venki

Attachment: apicid2.patch
Description: apicid2.patch