diff --git a/xen/arch/x86/acpi/wakeup_prot.S b/xen/arch/x86/acpi/wakeup_prot.S
index 8ce57ad137..a741d58b91 100644
--- a/xen/arch/x86/acpi/wakeup_prot.S
+++ b/xen/arch/x86/acpi/wakeup_prot.S
@@ -124,6 +124,8 @@ LABEL(s3_resume)
         mov     STACK_CPUINFO_FIELD(cr4)(%rbx), %rax
         mov     %rax, %cr4
 
+        call    mtrr_bp_restore
+
 .Lsuspend_err:
         pop     %r15
         pop     %r14
diff --git a/xen/arch/x86/cpu/mtrr/main.c b/xen/arch/x86/cpu/mtrr/main.c
index 39b18c6013..24cddcaddf 100644
--- a/xen/arch/x86/cpu/mtrr/main.c
+++ b/xen/arch/x86/cpu/mtrr/main.c
@@ -610,7 +610,7 @@ void mtrr_aps_sync_end(void)
 	hold_mtrr_updates_on_aps = 0;
 }
 
-void mtrr_bp_restore(void)
+void asmlinkage mtrr_bp_restore(void)
 {
 	if (mtrr_if)
 		mtrr_set_all();
diff --git a/xen/arch/x86/include/asm/mtrr.h b/xen/arch/x86/include/asm/mtrr.h
index 36dac0a775..48b59d2620 100644
--- a/xen/arch/x86/include/asm/mtrr.h
+++ b/xen/arch/x86/include/asm/mtrr.h
@@ -66,7 +66,6 @@ extern uint8_t pat_type_2_pte_flags(uint8_t pat_type);
 extern int hold_mtrr_updates_on_aps;
 extern void mtrr_aps_sync_begin(void);
 extern void mtrr_aps_sync_end(void);
-extern void mtrr_bp_restore(void);
 
 extern bool mtrr_var_range_msr_set(struct domain *d, struct mtrr_state *m,
                                    uint32_t msr, uint64_t msr_content);