xen: clean up xen_load_gdt
Makes the logic a bit clearer.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 70b355d3a..5776dc2 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -301,10 +301,21 @@
frames = mcs.args;
for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
- frames[f] = arbitrary_virt_to_mfn((void *)va);
+ int level;
+ pte_t *ptep = lookup_address(va, &level);
+ unsigned long pfn, mfn;
+ void *virt;
+
+ BUG_ON(ptep == NULL);
+
+ pfn = pte_pfn(*ptep);
+ mfn = pfn_to_mfn(pfn);
+ virt = __va(PFN_PHYS(pfn));
+
+ frames[f] = mfn;
make_lowmem_page_readonly((void *)va);
- make_lowmem_page_readonly(mfn_to_virt(frames[f]));
+ make_lowmem_page_readonly(virt);
}
MULTI_set_gdt(mcs.mc, frames, size / sizeof(struct desc_struct));