Patch "x86/cpu: Implement CPU vulnerabilites sysfs functions" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    x86/cpu: Implement CPU vulnerabilites sysfs functions

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     x86-cpu-implement-cpu-vulnerabilites-sysfs-functions.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 61dc0f555b5c761cdafb0ba5bd41ecf22d68a4c4 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Sun, 7 Jan 2018 22:48:01 +0100
Subject: x86/cpu: Implement CPU vulnerabilites sysfs functions

From: Thomas Gleixner <tglx@linutronix.de>

commit 61dc0f555b5c761cdafb0ba5bd41ecf22d68a4c4 upstream.

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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/x86/Kconfig           |    1 +
 arch/x86/kernel/cpu/bugs.c |   29 +++++++++++++++++++++++++++++
 2 files changed, 30 insertions(+)

--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -62,6 +62,7 @@ config X86
 	select GENERIC_CLOCKEVENTS_MIN_ADJUST
 	select GENERIC_CMOS_UPDATE
 	select GENERIC_CPU_AUTOPROBE
+	select GENERIC_CPU_VULNERABILITIES
 	select GENERIC_EARLY_IOREMAP
 	select GENERIC_FIND_FIRST_BIT
 	select GENERIC_IOMAP
--- 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>
@@ -49,3 +50,31 @@ void __init check_bugs(void)
 
 	fpu__init_check_bugs();
 }
+
+#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))
+		return sprintf(buf, "Not affected\n");
+	return sprintf(buf, "Vulnerable\n");
+}
+#endif


Patches currently in stable-queue which might be from tglx@linutronix.de are

queue-4.4/x86-mm-pat-dev-mem-remove-superfluous-error-message.patch
queue-4.4/x86-microcode-intel-extend-bdw-late-loading-with-a-revision-check.patch
queue-4.4/x86-alternatives-add-missing-n-at-end-of-alternative-inline-asm.patch
queue-4.4/sysfs-cpu-fix-typos-in-vulnerability-documentation.patch
queue-4.4/locking-mutex-allow-next-waiter-lockless-wakeup.patch
queue-4.4/x86-vsdo-fix-build-on-paravirt_clock-y-kvm_guest-n.patch
queue-4.4/x86-pti-efi-broken-conversion-from-efi-to-kernel-page-table.patch
queue-4.4/x86-documentation-add-pti-description.patch
queue-4.4/x86-acpi-handle-sci-interrupts-above-legacy-space-gracefully.patch
queue-4.4/x86-cpu-implement-cpu-vulnerabilites-sysfs-functions.patch
queue-4.4/futex-replace-barrier-in-unqueue_me-with-read_once.patch
queue-4.4/selftests-x86-add-test_vsyscall.patch
queue-4.4/sysfs-cpu-add-vulnerability-folder.patch
queue-4.4/x86-acpi-reduce-code-duplication-in-mp_override_legacy_irq.patch
queue-4.4/x86-alternatives-fix-optimize_nops-checking.patch