From: Rusty Russell <rusty@rustcorp.com.au>

Allow selected bug checks to be skipped by paravirt kernels.  The two most
important are the F00F workaround (which is either done by the hypervisor, or
not required), and the 'hlt' instruction check, which can break under some
hypervisors.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 arch/i386/kernel/cpu/intel.c |    2 +-
 include/asm-i386/bugs.h      |    4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff -puN arch/i386/kernel/cpu/intel.c~paravirtualization-allow-selected-bug-checks-to-be arch/i386/kernel/cpu/intel.c
--- a/arch/i386/kernel/cpu/intel.c~paravirtualization-allow-selected-bug-checks-to-be
+++ a/arch/i386/kernel/cpu/intel.c
@@ -107,7 +107,7 @@ static void __cpuinit init_intel(struct 
 	 * Note that the workaround only should be initialized once...
 	 */
 	c->f00f_bug = 0;
-	if ( c->x86 == 5 ) {
+	if (!paravirt_enabled() && c->x86 == 5) {
 		static int f00f_workaround_enabled = 0;
 
 		c->f00f_bug = 1;
diff -puN include/asm-i386/bugs.h~paravirtualization-allow-selected-bug-checks-to-be include/asm-i386/bugs.h
--- a/include/asm-i386/bugs.h~paravirtualization-allow-selected-bug-checks-to-be
+++ a/include/asm-i386/bugs.h
@@ -21,6 +21,7 @@
 #include <asm/processor.h>
 #include <asm/i387.h>
 #include <asm/msr.h>
+#include <asm/paravirt.h>
 
 static int __init no_halt(char *s)
 {
@@ -91,6 +92,9 @@ static void __init check_fpu(void)
 
 static void __init check_hlt(void)
 {
+	if (paravirt_enabled())
+		return;
+
 	printk(KERN_INFO "Checking 'hlt' instruction... ");
 	if (!boot_cpu_data.hlt_works_ok) {
 		printk("disabled\n");
_