On Thu, Sep 22, 2005 at 03:34:02PM +0200, Ingo Molnar wrote: > > * Andi Kleen <ak@xxxxxx> wrote: > > > > * This grunge runs the startup process for > > > * the targeted processor. > > > */ > > > + cpu_gdt_descr[cpu].address = __get_free_page(GFP_KERNEL|__GFP_ZERO); > > > > I can see why don't check it for NULL, but it's a ugly reason and > > would be better fixed. It at least needs a comment. > > it's so early in the bootup that any failure here would probably be > fatal anyway. But yeah, a comment would be nice. Not true for AP boot, especially with CPU hotplug. And CPU hotplug will be common because suspend/resume use it and next years laptops will have dual core CPUs. So it would be nicer to handle it. But getting out of that path is difficult. > > -Andi (who would still prefer just going back to the array in head.S - > > would work as well and waste less memory) > > that doesnt really solve the problem for e.g. Xen, which needs a > separate page for each GDT. (xenolinux is a separate arch right now, but > it will/should be merged back into its base architectures) So why not > solve all the problems at once? Xen could use the same method vmware uses that handles having other read only data in there too? Doesn't sound too bad. -Andi