3 files changed, 22 insertions, 14 deletions

diff --git a/Documentation/lguest/Makefile b/Documentation/lguest/Makefile
index bac037eb1cda..725eef81cd48 100644
--- a/Documentation/lguest/Makefile
+++ b/Documentation/lguest/Makefile
@@ -1,5 +1,5 @@
 # This creates the demonstration utility "lguest" which runs a Linux guest.
-CFLAGS:=-Wall -Wmissing-declarations -Wmissing-prototypes -O3 -I../../include
+CFLAGS:=-Wall -Wmissing-declarations -Wmissing-prototypes -O3 -I../../include -I../../arch/x86/include
 LDLIBS:=-lz
 
 all: lguest
diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c
index da86fd53856a..804520633fcf 100644
--- a/Documentation/lguest/lguest.c
+++ b/Documentation/lguest/lguest.c
@@ -44,7 +44,7 @@
 #include "linux/virtio_console.h"
 #include "linux/virtio_rng.h"
 #include "linux/virtio_ring.h"
-#include "asm-x86/bootparam.h"
+#include "asm/bootparam.h"
 /*L:110 We can ignore the 39 include files we need for this program, but I do
  * want to draw attention to the use of kernel-style types.
  *
diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index 48ee4f9435f4..a5d8e1ace1cf 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -367,10 +367,9 @@ static void lguest_cpuid(unsigned int *ax, unsigned int *bx,
  * lazily after a task switch, and Linux uses that gratefully, but wouldn't a
  * name like "FPUTRAP bit" be a little less cryptic?
  *
- * We store cr0 (and cr3) locally, because the Host never changes it.  The
- * Guest sometimes wants to read it and we'd prefer not to bother the Host
- * unnecessarily. */
-static unsigned long current_cr0, current_cr3;
+ * We store cr0 locally because the Host never changes it.  The Guest sometimes
+ * wants to read it and we'd prefer not to bother the Host unnecessarily. */
+static unsigned long current_cr0;
 static void lguest_write_cr0(unsigned long val)
 {
         lazy_hcall(LHCALL_TS, val & X86_CR0_TS, 0, 0);
@@ -399,17 +398,23 @@ static unsigned long lguest_read_cr2(void)
         return lguest_data.cr2;
 }
 
+/* See lguest_set_pte() below. */
+static bool cr3_changed = false;
+
 /* cr3 is the current toplevel pagetable page: the principle is the same as
- * cr0.  Keep a local copy, and tell the Host when it changes. */
+ * cr0.  Keep a local copy, and tell the Host when it changes.  The only
+ * difference is that our local copy is in lguest_data because the Host needs
+ * to set it upon our initial hypercall. */
 static void lguest_write_cr3(unsigned long cr3)
 {
+        lguest_data.pgdir = cr3;
         lazy_hcall(LHCALL_NEW_PGTABLE, cr3, 0, 0);
-        current_cr3 = cr3;
+        cr3_changed = true;
 }
 
 static unsigned long lguest_read_cr3(void)
 {
-        return current_cr3;
+        return lguest_data.pgdir;
 }
 
 /* cr4 is used to enable and disable PGE, but we don't care. */
@@ -498,13 +503,13 @@ static void lguest_set_pmd(pmd_t *pmdp, pmd_t pmdval)
  * to forget all of them.  Fortunately, this is very rare.
  *
  * ... except in early boot when the kernel sets up the initial pagetables,
- * which makes booting astonishingly slow.  So we don't even tell the Host
- * anything changed until we've done the first page table switch. */
+ * which makes booting astonishingly slow: 1.83 seconds!  So we don't even tell
+ * the Host anything changed until we've done the first page table switch,
+ * which brings boot back to 0.25 seconds. */
 static void lguest_set_pte(pte_t *ptep, pte_t pteval)
 {
         *ptep = pteval;
-        /* Don't bother with hypercall before initial setup. */
-        if (current_cr3)
+        if (cr3_changed)
                 lazy_hcall(LHCALL_FLUSH_TLB, 1, 0, 0);
 }
 
@@ -521,7 +526,7 @@ static void lguest_set_pte(pte_t *ptep, pte_t pteval)
 static void lguest_flush_tlb_single(unsigned long addr)
 {
         /* Simply set it to zero: if it was not, it will fault back in. */
-        lazy_hcall(LHCALL_SET_PTE, current_cr3, addr, 0);
+        lazy_hcall(LHCALL_SET_PTE, lguest_data.pgdir, addr, 0);
 }
 
 /* This is what happens after the Guest has removed a large number of entries.
@@ -581,6 +586,9 @@ static void __init lguest_init_IRQ(void)
 
         for (i = 0; i < LGUEST_IRQS; i++) {
                 int vector = FIRST_EXTERNAL_VECTOR + i;
+                /* Some systems map "vectors" to interrupts weirdly.  Lguest has
+                 * a straightforward 1 to 1 mapping, so force that here. */
+                __get_cpu_var(vector_irq)[vector] = i;
                 if (vector != SYSCALL_VECTOR) {
                         set_intr_gate(vector, interrupt[vector]);
                         set_irq_chip_and_handler_name(i, &lguest_irq_controller,