Merge git://github.com/rustyrussell/linux

* git://github.com/rustyrussell/linux:
  lguest: move process freezing before pending signals check
  lguest: don't allow KVM-detection cpuid.
  lguest: Allow running under paravirt-enabled KVM.

2 files changed, 18 insertions, 8 deletions

diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index 13ee258442ae..f63da5ef217c 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -70,6 +70,7 @@
 #include <asm/i387.h>
 #include <asm/stackprotector.h>
 #include <asm/reboot.h>         /* for struct machine_ops */
+#include <asm/kvm_para.h>
 
 /*G:010
  * Welcome to the Guest!
@@ -455,6 +456,15 @@ static void lguest_cpuid(unsigned int *ax, unsigned int *bx,
                 *ax &= 0xFFFFF0FF;
                 *ax |= 0x00000500;
                 break;
+
+        /*
+         * This is used to detect if we're running under KVM.  We might be,
+         * but that's a Host matter, not us.  So say we're not.
+         */
+        case KVM_CPUID_SIGNATURE:
+                *bx = *cx = *dx = 0;
+                break;
+
         /*
          * 0x80000000 returns the highest Extended Function, so we futureproof
          * like we do above by limiting it to known fields.
diff --git a/drivers/lguest/core.c b/drivers/lguest/core.c
index 2535933c49f8..b5fdcb78a75b 100644
--- a/drivers/lguest/core.c
+++ b/drivers/lguest/core.c
@@ -232,6 +232,13 @@ int run_guest(struct lg_cpu *cpu, unsigned long __user *user)
                         }
                 }
 
+                /*
+                 * All long-lived kernel loops need to check with this horrible
+                 * thing called the freezer.  If the Host is trying to suspend,
+                 * it stops us.
+                 */
+                try_to_freeze();
+
                 /* Check for signals */
                 if (signal_pending(current))
                         return -ERESTARTSYS;
@@ -246,13 +253,6 @@ int run_guest(struct lg_cpu *cpu, unsigned long __user *user)
                         try_deliver_interrupt(cpu, irq, more);
 
                 /*
-                 * All long-lived kernel loops need to check with this horrible
-                 * thing called the freezer.  If the Host is trying to suspend,
-                 * it stops us.
-                 */
-                try_to_freeze();
-
-                /*
                  * Just make absolutely sure the Guest is still alive.  One of
                  * those hypercalls could have been fatal, for example.
                  */
@@ -313,7 +313,7 @@ static int __init init(void)
         int err;
 
         /* Lguest can't run under Xen, VMI or itself.  It does Tricky Stuff. */
-        if (paravirt_enabled()) {
+        if (get_kernel_rpl() != 0) {
                 printk("lguest is afraid of being a guest\n");
                 return -EPERM;
         }