Cc: Andi Kleen <ak@...>, William Lee Irwin III <wli@...>, Ingo Molnar <mingo@...>, Thomas Gleixner <tglx@...>, Andrew Morton <akpm@...>, Linux Kernel Mailing List <linux-kernel@...>
Yes, Xen requires it for PAE pgds, at least at the moment. But native,
lguest, vmi and kvm don't. I'd made it so that the memory overhead was
only paid in the Xen case. Allocating a whole page all the time
certainly simplifies things, but at the cost of more overhead for everyone.
If we move away from using the page->private field to link the pgds
together, then I can probably remove Xen's need to allocate a whole page
for PAE pgds.
J
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