From: Chuck Anderson <chuck.anderson@oracle.com>
Date: Mon, 26 Feb 2018 09:27:37 +0000 (-0800)
Subject: retpoline: display IBPB feature status along with IBRS status
X-Git-Tag: v4.1.12-124.31.3~1105
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=d550e0c92e1987991428a4233e91a84f7bccbe03;p=users%2Fjedix%2Flinux-maple.git

retpoline: display IBPB feature status along with IBRS status

retpoline_enabled() lists if the IBRS mitigation is in use and if the
kernel was compiled with retpoline.  Add whether IBPB is in use to the
list.

Orabug: 27625404
Signed-off-by: Chuck Anderson <chuck.anderson@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
---

diff --git a/arch/x86/kernel/cpu/bugs_64.c b/arch/x86/kernel/cpu/bugs_64.c
index 21cad468d13e..30279fe2976f 100644
--- a/arch/x86/kernel/cpu/bugs_64.c
+++ b/arch/x86/kernel/cpu/bugs_64.c
@@ -431,8 +431,9 @@ retpoline_auto:
 		mode = retp_compiler() ? SPECTRE_V2_RETPOLINE_GENERIC :
 					 SPECTRE_V2_RETPOLINE_MINIMAL;
 
-		pr_info("Options: %s%s\n",
+		pr_info("Options: %s%s%s\n",
 			check_ibrs_inuse() ? "IBRS " : "",
+			check_ibpb_inuse() ? "IBPB " : "",
 			retp_compiler() ? "retpoline" : "");
 
 		/* IBRS available. Lets see if we are compiled with retpoline. */
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index 67a1ea0173d0..5d0cd6bcc459 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -161,16 +161,19 @@ void init_scattered_cpuid_features(struct cpuinfo_x86 *c,
 			ignore = true;
 
 		if (boot_cpu_has(X86_FEATURE_IBRS)) {
-			printk(KERN_INFO "FEATURE SPEC_CTRL Present%s\n", ignore ? " but ignored (Xen)": "");
-			if (ignore)
-				return;
-		} else if (boot_cpu_has(X86_FEATURE_IBPB)) {
-			printk_once(KERN_INFO "FEATURE IBPB Present%s\n", ignore ? " but ignored (Xen)": "");
-			if (ignore)
-				return;
+			printk_once(KERN_INFO "FEATURE SPEC_CTRL Present%s\n",
+				    ignore ? " but ignored (Xen)": "");
 		} else {
 			printk(KERN_INFO "FEATURE SPEC_CTRL Not Present\n");
 		}
+		if (boot_cpu_has(X86_FEATURE_IBPB)) {
+			printk_once(KERN_INFO "FEATURE IBPB Present%s\n",
+					    ignore ? " but ignored (Xen)": "");
+		} else {
+			printk(KERN_INFO "FEATURE IBPB Not Present\n");
+		}
+		if (ignore)
+			return;
 	}
 
 	if ((cpu_has(c, X86_FEATURE_IBRS) ||