* Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> wrote: > On Maw, 2005-11-08 at 04:53 -0800, Zachary Amsden wrote: > > Can't hurt, and APM is largely obsolete because of ACPI, so I'm only > > concerned with trimming and keeping adequate protection of the kernel > > from APM code while maintaining correctness. I don't have a nice set of > > old machines with enough wacky APM BIOSen to validate that unpinning the > > CPU is ok. > > A large number of SMP machines, probably the majority of APM based > ones require that APM calls occur on CPU#0. As I understand it from a > BIOS engineer involved in debugging that problem Redmond always does > APM from CPU #0 and may even guarantee it. ok, then i'm all for making that more explicit - i.e. Zachary's patch is the right one. Ingo
