under paravirt, read cr2 cannot be issued directly anymore.
So wrap it in a macro, defined to the operation itself in case
paravirt is off, but to something else if we have paravirt
in the game

Signed-off-by: Glauber de Oliveira Costa <[EMAIL PROTECTED]>
Signed-off-by: Steven Rostedt <[EMAIL PROTECTED]>
---
 arch/x86_64/kernel/head.S |   10 +++++++++-
 1 files changed, 9 insertions(+), 1 deletions(-)

diff --git a/arch/x86_64/kernel/head.S b/arch/x86_64/kernel/head.S
index e89abcd..1bb6c55 100644
--- a/arch/x86_64/kernel/head.S
+++ b/arch/x86_64/kernel/head.S
@@ -18,6 +18,12 @@
 #include <asm/page.h>
 #include <asm/msr.h>
 #include <asm/cache.h>
+#ifdef CONFIG_PARAVIRT
+#include <asm/asm-offsets.h>
+#include <asm/paravirt.h>
+#else
+#define GET_CR2_INTO_RCX mov %cr2, %rcx
+#endif
 
 /* we are not able to switch in one step to the final KERNEL ADRESS SPACE
  * because we need identity-mapped pages.
@@ -267,7 +273,9 @@ ENTRY(early_idt_handler)
        xorl %eax,%eax
        movq 8(%rsp),%rsi       # get rip
        movq (%rsp),%rdx
-       movq %cr2,%rcx
+       /* When PARAVIRT is on, this operation may clobber rax. It is
+         something safe to do, because we've just zeroed rax. */
+       GET_CR2_INTO_RCX
        leaq early_idt_msg(%rip),%rdi
        call early_printk
        cmpl $2,early_recursion_flag(%rip)
-- 
1.4.4.2

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