[PATCH] i386: Page-align the GDT

Xen wants a dedicated page for the GDT.  I believe VMI likes it too.
lguest, KVM and native don't care.

Simple transformation to page-aligned "struct gdt_page".

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com>

1 files changed, 7 insertions, 2 deletions

diff --git a/include/asm-i386/desc.h b/include/asm-i386/desc.h
index 4a974064e928..c547403f341d 100644
--- a/include/asm-i386/desc.h
+++ b/include/asm-i386/desc.h
@@ -18,10 +18,15 @@ struct Xgt_desc_struct {
         unsigned short pad;
 } __attribute__ ((packed));
 
-DECLARE_PER_CPU(struct desc_struct, cpu_gdt[GDT_ENTRIES]);
+struct gdt_page
+{
+        struct desc_struct gdt[GDT_ENTRIES];
+} __attribute__((aligned(PAGE_SIZE)));
+DECLARE_PER_CPU(struct gdt_page, gdt_page);
+
 static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu)
 {
-        return per_cpu(cpu_gdt, cpu);
+        return per_cpu(gdt_page, cpu).gdt;
 }
 
 extern struct Xgt_desc_struct idt_descr;