From: Chuck Anderson <chuck.anderson@oracle.com>
Date: Mon, 12 Feb 2018 06:27:25 +0000 (-0800)
Subject: retpoline/module: add bit defs for use_ibpb
X-Git-Tag: v4.1.12-124.31.3~1113
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=8bd019739319bb4ee04d0b16094fb39a97c38bb8;p=users%2Fjedix%2Flinux-maple.git

retpoline/module: add bit defs for use_ibpb

Replace bit references for IBPB state in use_ibpb with:

    SPEC_CTRL_IBPB_INUSE
    SPEC_CTRL_IBPB_SUPPORTED
    SPEC_CTRL_IBPB_ADMIN_DISABLED

Change comment block describing use_ibrs flags to use symbolic values.
Remove duplicate comment block describing flag values in use_ibrs and use_ibpb.
Cosmetic change to defs for sysctl_ibrs_enabled, sysctl_ibpb_enabled and
sysctl_lfence_enabled in preparation for adding additional sysctl_* values.

Orabug: 27457549

Signed-off-by: Chuck Anderson <chuck.anderson@oracle.com>
Signed-off-by: Brian Maly <brian.maly@oracle.com>

Conflicts:
	arch/x86/kernel/cpu/spec_ctrl.c
---

diff --git a/arch/x86/include/asm/spec_ctrl.h b/arch/x86/include/asm/spec_ctrl.h
index d32e6bb9fc42..f0e75ffab225 100644
--- a/arch/x86/include/asm/spec_ctrl.h
+++ b/arch/x86/include/asm/spec_ctrl.h
@@ -278,25 +278,29 @@ static inline void clear_ibrs_disabled(void)
 extern int use_ibpb;
 extern u32 sysctl_ibpb_enabled;
 
-#define ibpb_supported		(use_ibpb & 0x2)
-#define ibpb_disabled		(use_ibpb & 0x4)
+#define SPEC_CTRL_IBPB_INUSE		(1<<0)	/* OS enables IBPB usage */
+#define SPEC_CTRL_IBPB_SUPPORTED	(1<<1)	/* System supports IBPB */
+#define SPEC_CTRL_IBPB_ADMIN_DISABLED	(1<<2)	/* Admin disables IBPB */
+
+#define ibpb_supported		(use_ibpb & SPEC_CTRL_IBPB_SUPPORTED)
+#define ibpb_disabled		(use_ibpb & SPEC_CTRL_IBPB_ADMIN_DISABLED)
 
 #define ibpb_inuse		(check_ibpb_inuse())
 
 static inline void set_ibpb_inuse(void)
 {
 	if (ibpb_supported)
-		use_ibpb |= 0x1;
+		use_ibpb |= SPEC_CTRL_IBPB_INUSE;
 }
 
 static inline void clear_ibpb_inuse(void)
 {
-	use_ibpb &= ~0x1;
+	use_ibpb &= ~SPEC_CTRL_IBPB_INUSE;
 }
 
 static inline int check_ibpb_inuse(void)
 {
-	if (use_ibpb & 0x1)
+	if (use_ibpb & SPEC_CTRL_IBPB_INUSE)
 		return 1;
 	else
 		/* rmb to prevent wrong speculation for security */
@@ -306,14 +310,14 @@ static inline int check_ibpb_inuse(void)
 
 static inline void set_ibpb_supported(void)
 {
-	use_ibpb |= 0x2;
+	use_ibpb |= SPEC_CTRL_IBPB_SUPPORTED;
 	if (!ibpb_disabled)
 		set_ibpb_inuse();
 }
 
 static inline void set_ibpb_disabled(void)
 {
-	use_ibpb |= 0x4;
+	use_ibpb |= SPEC_CTRL_IBPB_ADMIN_DISABLED;
 	if (check_ibpb_inuse())
 		clear_ibpb_inuse();
 	/* Update what sysfs shows. */
@@ -322,7 +326,7 @@ static inline void set_ibpb_disabled(void)
 
 static inline void clear_ibpb_disabled(void)
 {
-	use_ibpb &= ~0x4;
+	use_ibpb &= ~SPEC_CTRL_IBPB_ADMIN_DISABLED;
 	set_ibpb_inuse();
 	/* Update what sysfs shows. */
 	sysctl_ibpb_enabled = ibpb_inuse ? 1 : 0;
diff --git a/arch/x86/kernel/cpu/bugs_64.c b/arch/x86/kernel/cpu/bugs_64.c
index 5ae5dcdb5464..3eeff1bcd364 100644
--- a/arch/x86/kernel/cpu/bugs_64.c
+++ b/arch/x86/kernel/cpu/bugs_64.c
@@ -21,19 +21,19 @@
 #include <asm/intel-family.h>
 
 /*
- * use IBRS
- * bit 0 = indicate if ibrs is currently in use
- * bit 1 = indicate if system supports ibrs
- * bit 2 = indicate if admin disables ibrs
+ * use_ibrs flags:
+ * SPEC_CTRL_IBRS_INUSE			indicate if ibrs is currently in use
+ * SPEC_CTRL_IBRS_SUPPORTED		indicate if system supports ibrs
+ * SPEC_CTRL_IBRS_ADMIN_DISABLED	indicate if admin disables ibrs
  */
 int use_ibrs;
 EXPORT_SYMBOL(use_ibrs);
 
 /*
- * use IBRS
- * bit 0 = indicate if ibpb is currently in use
- * bit 1 = indicate if system supports ibpb
- * bit 2 = indicate if admin disables ibpb
+ * use_ibpb flags:
+ * SPEC_CTRL_IBPB_INUSE			indicate if ibpb is currently in use
+ * SPEC_CTRL_IBPB_SUPPORTED		indicate if system supports ibpb
+ * SPEC_CTRL_IBPB_ADMIN_DISABLED	indicate if admin disables ibpb
  */
 int use_ibpb;
 EXPORT_SYMBOL(use_ibpb);
diff --git a/arch/x86/kernel/cpu/spec_ctrl.c b/arch/x86/kernel/cpu/spec_ctrl.c
index a568124222d3..a880b7065620 100644
--- a/arch/x86/kernel/cpu/spec_ctrl.c
+++ b/arch/x86/kernel/cpu/spec_ctrl.c
@@ -8,14 +8,8 @@
 #include <asm/cpufeature.h>
 #include <asm/microcode.h>
 
-/*
- * use_ibrs
- * bit 0 = indicate if ibrs is currently in use
- * bit 1 = indicate if system supports ibrs
- * bit 2 = indicate if admin disables ibrs
- */
-
-u32 sysctl_ibrs_enabled = 0, sysctl_ibpb_enabled = 0;
+u32 sysctl_ibrs_enabled;
+u32 sysctl_ibpb_enabled;
 EXPORT_SYMBOL(sysctl_ibrs_enabled);
 EXPORT_SYMBOL(sysctl_ibpb_enabled);