2 files changed, 44 insertions, 49 deletions

diff --git a/arch/x86/include/asm/spec-ctrl.h b/arch/x86/include/asm/spec-ctrl.h
index 82b6c5a0d61e..9cecbe5e57ee 100644
--- a/arch/x86/include/asm/spec-ctrl.h
+++ b/arch/x86/include/asm/spec-ctrl.h
@@ -13,10 +13,35 @@
  * Takes the guest view of SPEC_CTRL MSR as a parameter and also
  * the guest's version of VIRT_SPEC_CTRL, if emulated.
  */
-extern void x86_spec_ctrl_set_guest(u64 guest_spec_ctrl,
-                                    u64 guest_virt_spec_ctrl);
-extern void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl,
-                                       u64 guest_virt_spec_ctrl);
+extern void x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool guest);
+
+/**
+ * x86_spec_ctrl_set_guest - Set speculation control registers for the guest
+ * @guest_spec_ctrl:            The guest content of MSR_SPEC_CTRL
+ * @guest_virt_spec_ctrl:       The guest controlled bits of MSR_VIRT_SPEC_CTRL
+ *                              (may get translated to MSR_AMD64_LS_CFG bits)
+ *
+ * Avoids writing to the MSR if the content/bits are the same
+ */
+static inline
+void x86_spec_ctrl_set_guest(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl)
+{
+        x86_virt_spec_ctrl(guest_spec_ctrl, guest_virt_spec_ctrl, true);
+}
+
+/**
+ * x86_spec_ctrl_restore_host - Restore host speculation control registers
+ * @guest_spec_ctrl:            The guest content of MSR_SPEC_CTRL
+ * @guest_virt_spec_ctrl:       The guest controlled bits of MSR_VIRT_SPEC_CTRL
+ *                              (may get translated to MSR_AMD64_LS_CFG bits)
+ *
+ * Avoids writing to the MSR if the content/bits are the same
+ */
+static inline
+void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl)
+{
+        x86_virt_spec_ctrl(guest_spec_ctrl, guest_virt_spec_ctrl, false);
+}
 
 /* AMD specific Speculative Store Bypass MSR data */
 extern u64 x86_amd_ls_cfg_base;
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index f2f0c1b3bf50..feb7d597c265 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -151,55 +151,25 @@ u64 x86_spec_ctrl_get_default(void)
 }
 EXPORT_SYMBOL_GPL(x86_spec_ctrl_get_default);
 
-/**
- * x86_spec_ctrl_set_guest - Set speculation control registers for the guest
- * @guest_spec_ctrl:            The guest content of MSR_SPEC_CTRL
- * @guest_virt_spec_ctrl:       The guest controlled bits of MSR_VIRT_SPEC_CTRL
- *                              (may get translated to MSR_AMD64_LS_CFG bits)
- *
- * Avoids writing to the MSR if the content/bits are the same
- */
-void x86_spec_ctrl_set_guest(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl)
+void
+x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool setguest)
 {
-        u64 host = x86_spec_ctrl_base;
+        struct thread_info *ti = current_thread_info();
+        u64 msr, host = x86_spec_ctrl_base;
 
         /* Is MSR_SPEC_CTRL implemented ? */
-        if (!static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL))
-                return;
-
-        /* SSBD controlled in MSR_SPEC_CTRL */
-        if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD))
-                host |= ssbd_tif_to_spec_ctrl(current_thread_info()->flags);
-
-        if (host != guest_spec_ctrl)
-                wrmsrl(MSR_IA32_SPEC_CTRL, guest_spec_ctrl);
-}
-EXPORT_SYMBOL_GPL(x86_spec_ctrl_set_guest);
-
-/**
- * x86_spec_ctrl_restore_host - Restore host speculation control registers
- * @guest_spec_ctrl:            The guest content of MSR_SPEC_CTRL
- * @guest_virt_spec_ctrl:       The guest controlled bits of MSR_VIRT_SPEC_CTRL
- *                              (may get translated to MSR_AMD64_LS_CFG bits)
- *
- * Avoids writing to the MSR if the content/bits are the same
- */
-void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl)
-{
-        u64 host = x86_spec_ctrl_base;
-
-        /* Is MSR_SPEC_CTRL implemented ? */
-        if (!static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL))
-                return;
-
-        /* SSBD controlled in MSR_SPEC_CTRL */
-        if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD))
-                host |= ssbd_tif_to_spec_ctrl(current_thread_info()->flags);
-
-        if (host != guest_spec_ctrl)
-                wrmsrl(MSR_IA32_SPEC_CTRL, host);
+        if (static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL)) {
+                /* SSBD controlled in MSR_SPEC_CTRL */
+                if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD))
+                        host |= ssbd_tif_to_spec_ctrl(ti->flags);
+
+                if (host != guest_spec_ctrl) {
+                        msr = setguest ? guest_spec_ctrl : host;
+                        wrmsrl(MSR_IA32_SPEC_CTRL, msr);
+                }
+        }
 }
-EXPORT_SYMBOL_GPL(x86_spec_ctrl_restore_host);
+EXPORT_SYMBOL_GPL(x86_virt_spec_ctrl);
 
 static void x86_amd_ssb_disable(void)
 {