lguest: fix guest crash on non-linear addresses in gdt pvops

[deliverable/linux.git] / arch / x86 / lguest / boot.c

diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index e94a11e42f9864a35e197d9fdf7919accc8ba095..a2085368a3dcd37b50037cc22bf1e82737a500ca 100644 (file)
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -273,15 +273,15 @@ static void lguest_load_idt(const struct desc_ptr *desc)
  * controls the entire thing and the Guest asks it to make changes using the
  * LOAD_GDT hypercall.
  *
- * This is the opposite of the IDT code where we have a LOAD_IDT_ENTRY
- * hypercall and use that repeatedly to load a new IDT.  I don't think it
- * really matters, but wouldn't it be nice if they were the same?  Wouldn't
- * it be even better if you were the one to send the patch to fix it?
+ * This is the exactly like the IDT code.
  */
 static void lguest_load_gdt(const struct desc_ptr *desc)
 {
-       BUG_ON((desc->size + 1) / 8 != GDT_ENTRIES);
-       kvm_hypercall2(LHCALL_LOAD_GDT, __pa(desc->address), GDT_ENTRIES);
+       unsigned int i;
+       struct desc_struct *gdt = (void *)desc->address;
+
+       for (i = 0; i < (desc->size+1)/8; i++)
+               kvm_hypercall3(LHCALL_LOAD_GDT_ENTRY, i, gdt[i].a, gdt[i].b);
 }
 
 /* For a single GDT entry which changes, we do the lazy thing: alter our GDT,
@@ -291,7 +291,9 @@ static void lguest_write_gdt_entry(struct desc_struct *dt, int entrynum,
                                   const void *desc, int type)
 {
        native_write_gdt_entry(dt, entrynum, desc, type);
-       kvm_hypercall2(LHCALL_LOAD_GDT, __pa(dt), GDT_ENTRIES);
+       /* Tell Host about this new entry. */
+       kvm_hypercall3(LHCALL_LOAD_GDT_ENTRY, entrynum,
+                      dt[entrynum].a, dt[entrynum].b);
 }
 
 /* OK, I lied.  There are three "thread local storage" GDT entries which change