From: Thomas Gleixner <tglx@linutronix.de>
Date: Thu, 11 Jan 2018 22:17:08 +0000 (-0500)
Subject: x86/cpu: Implement CPU vulnerabilites sysfs functions
X-Git-Tag: v4.1.12-124.31.3~1260
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=b54251b05f7f9b8616b92233b3d34f2a20bcab01;p=users%2Fjedix%2Flinux-maple.git

x86/cpu: Implement CPU vulnerabilites sysfs functions

Implement the CPU vulnerabilty show functions for meltdown, spectre_v1 and
spectre_v2.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Link: https://lkml.kernel.org/r/20180107214913.177414879@linutronix.de

(cherry picked from commit 61dc0f555b5c761cdafb0ba5bd41ecf22d68a4c4)
Orabug: 27353383
Signed-off-by: Kanth Ghatraju <kanth.ghatraju@oracle.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>

Conflicts:
	arch/x86/Kconfig

	Resolved conflicts to pick only the changes from the patches.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index faee499648cc7..0daf3ec56d690 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -54,6 +54,7 @@ config X86
 	select HAVE_DMA_ATTRS
 	select HAVE_DMA_CONTIGUOUS
 	select HAVE_KRETPROBES
+	select GENERIC_CPU_VULNERABILITIES
 	select GENERIC_EARLY_IOREMAP
 	select HAVE_OPTPROBES
 	select HAVE_KPROBES_ON_FTRACE
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 4c7dd836304a0..d178101e57b69 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -9,6 +9,7 @@
  */
 #include <linux/init.h>
 #include <linux/utsname.h>
+#include <linux/cpu.h>
 #include <asm/bugs.h>
 #include <asm/processor.h>
 #include <asm/processor-flags.h>
diff --git a/arch/x86/kernel/cpu/bugs_64.c b/arch/x86/kernel/cpu/bugs_64.c
index 04f0fe5af83ec..6a9b2a18156c1 100644
--- a/arch/x86/kernel/cpu/bugs_64.c
+++ b/arch/x86/kernel/cpu/bugs_64.c
@@ -31,3 +31,32 @@ void __init check_bugs(void)
 	if (!direct_gbpages)
 		set_memory_4k((unsigned long)__va(0), 1);
 }
+
+#ifdef CONFIG_SYSFS
+ssize_t cpu_show_meltdown(struct device *dev,
+			  struct device_attribute *attr, char *buf)
+{
+	if (!boot_cpu_has_bug(X86_BUG_CPU_MELTDOWN))
+		return sprintf(buf, "Not affected\n");
+	if (boot_cpu_has(X86_FEATURE_PTI))
+		return sprintf(buf, "Mitigation: PTI\n");
+	return sprintf(buf, "Vulnerable\n");
+}
+
+ssize_t cpu_show_spectre_v1(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1))
+		return sprintf(buf, "Not affected\n");
+	return sprintf(buf, "Vulnerable\n");
+}
+
+ssize_t cpu_show_spectre_v2(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2) ||
+	    (ibrs_inuse && ibpb_inuse))
+		return sprintf(buf, "Not affected\n");
+	return sprintf(buf, "Vulnerable\n");
+}
+#endif