When KASLR memory randomization is used, __PAGE_OFFSET is a global
variable changed during boot. The assembly code was using the variable
as an immediate value to calculate the cr3 physical address. The
physical address was incorrect resulting to a GP fault.

Signed-off-by: Thomas Garnier <thgar...@google.com>
---
 arch/x86/power/hibernate_asm_64.S | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/arch/x86/power/hibernate_asm_64.S 
b/arch/x86/power/hibernate_asm_64.S
index 8eee0e9..8db4905 100644
--- a/arch/x86/power/hibernate_asm_64.S
+++ b/arch/x86/power/hibernate_asm_64.S
@@ -23,6 +23,16 @@
 #include <asm/processor-flags.h>
 #include <asm/frame.h>
 
+/*
+ * A global variable holds the page_offset when KASLR memory randomization
+ * is enabled.
+ */
+#ifdef CONFIG_RANDOMIZE_MEMORY
+#define __PAGE_OFFSET_REF __PAGE_OFFSET
+#else
+#define __PAGE_OFFSET_REF $__PAGE_OFFSET
+#endif
+
 ENTRY(swsusp_arch_suspend)
        movq    $saved_context, %rax
        movq    %rsp, pt_regs_sp(%rax)
@@ -72,7 +82,7 @@ ENTRY(restore_image)
        /* code below has been relocated to a safe page */
 ENTRY(core_restore_code)
        /* switch to temporary page tables */
-       movq    $__PAGE_OFFSET, %rcx
+       movq    __PAGE_OFFSET_REF, %rcx
        subq    %rcx, %rax
        movq    %rax, %cr3
        /* flush TLB */
-- 
2.8.0.rc3.226.g39d4020

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