KVM: MMU: only write protect mappings at pagetable level
KVM: MMU: only write protect mappings at pagetable level

If a pagetable contains a writeable large spte, all of its sptes will be
write protected, including non-leaf ones, leading to endless pagefaults.

Do not write protect pages above PT_PAGE_TABLE_LEVEL, as the spte fault
paths assume non-leaf sptes are writable.

Tested-by: Alex Williamson <7469de9b95ba379e2656fa9677689657c47a7690@redhat.com>
Signed-off-by: Marcelo Tosatti <958bcd1f4a7a8c36dca09fe3fa9cb5f1483adf51@redhat.com>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs