1 files changed, 20 insertions, 15 deletions

diff --git a/arch/x86/lguest/i386_head.S b/arch/x86/lguest/i386_head.S
index 4f420c2f2d55..6ddfe4fc23c3 100644
--- a/arch/x86/lguest/i386_head.S
+++ b/arch/x86/lguest/i386_head.S
@@ -6,18 +6,22 @@
 #include <asm/processor-flags.h>
 
 /*G:020
- * Our story starts with the kernel booting into startup_32 in
- * arch/x86/kernel/head_32.S.  It expects a boot header, which is created by
- * the bootloader (the Launcher in our case).
+
+ * Our story starts with the bzImage: booting starts at startup_32 in
+ * arch/x86/boot/compressed/head_32.S.  This merely uncompresses the real
+ * kernel in place and then jumps into it: startup_32 in
+ * arch/x86/kernel/head_32.S.  Both routines expects a boot header in the %esi
+ * register, which is created by the bootloader (the Launcher in our case).
  *
  * The startup_32 function does very little: it clears the uninitialized global
  * C variables which we expect to be zero (ie. BSS) and then copies the boot
- * header and kernel command line somewhere safe.  Finally it checks the
- * 'hardware_subarch' field.  This was introduced in 2.6.24 for lguest and Xen:
- * if it's set to '1' (lguest's assigned number), then it calls us here.
+ * header and kernel command line somewhere safe, and populates some initial
+ * page tables.  Finally it checks the 'hardware_subarch' field.  This was
+ * introduced in 2.6.24 for lguest and Xen: if it's set to '1' (lguest's
+ * assigned number), then it calls us here.
  *
  * WARNING: be very careful here!  We're running at addresses equal to physical
- * addesses (around 0), not above PAGE_OFFSET as most code expectes
+ * addresses (around 0), not above PAGE_OFFSET as most code expects
  * (eg. 0xC0000000).  Jumps are relative, so they're OK, but we can't touch any
  * data without remembering to subtract __PAGE_OFFSET!
  *
@@ -27,13 +31,18 @@
 .section .init.text, "ax", @progbits
 ENTRY(lguest_entry)
         /*
-         * We make the "initialization" hypercall now to tell the Host about
-         * us, and also find out where it put our page tables.
+         * We make the "initialization" hypercall now to tell the Host where
+         * our lguest_data struct is.
          */
         movl $LHCALL_LGUEST_INIT, %eax
         movl $lguest_data - __PAGE_OFFSET, %ebx
         int $LGUEST_TRAP_ENTRY
 
+        /* Now turn our pagetables on; setup by arch/x86/kernel/head_32.S. */
+        movl $LHCALL_NEW_PGTABLE, %eax
+        movl $(initial_page_table - __PAGE_OFFSET), %ebx
+        int $LGUEST_TRAP_ENTRY
+
         /* Set up the initial stack so we can run C code. */
         movl $(init_thread_union+THREAD_SIZE),%esp
 
@@ -96,12 +105,8 @@ send_interrupts:
          */
         pushl %eax
         movl $LHCALL_SEND_INTERRUPTS, %eax
-        /*
-         * This is a vmcall instruction (same thing that KVM uses).  Older
-         * assembler versions might not know the "vmcall" instruction, so we
-         * create one manually here.
-         */
-        .byte 0x0f,0x01,0xc1 /* KVM_HYPERCALL */
+        /* This is the actual hypercall trap. */
+        int  $LGUEST_TRAP_ENTRY
         /* Put eax back the way we found it. */
         popl %eax
         ret