mybin

commit 6ec6a33a51fc4275345d0614334fd8ed863a572c
parent 6c91a13f731e4c9e1fded7f6cbcdff41af13556a
Author: Antoine Amarilli <a3nm@a3nm.net>
Date:   Sun, 25 Jun 2017 21:27:36 +0200

detect_hyperthreading_bug

Diffstat:
detect_hyperthreading_bug
 | 
65
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

1 file changed, 65 insertions(+), 0 deletions(-)
diff --git a/detect_hyperthreading_bug b/detect_hyperthreading_bug
@@ -0,0 +1,65 @@
+#!/usr/bin/perl
+# Copyright 2017 Uwe Kleine-König
+#
+# This program is free software; you can redistribute it and/or modify it under
+# the terms of the GNU General Public License version 2 as published by the
+# Free Software Foundation.
+#
+# https://lists.debian.org/debian-user/2017/06/msg01011.html
+
+open(my $cpuinfo, "</proc/cpuinfo") or die "failed to open cpuinfo\n";
+
+my $cpunum, $vendor, $family, $model, $stepping, $microcoderev, $hyperthreading;
+
+while (<$cpuinfo>) {
+	if (/^$/) {
+		print "cpu $cpunum: ";
+		if ($vendor eq "GenuineIntel" and $family == 6) {
+			if ($model == 78 or $model == 94) {
+				if ($stepping eq "3") {
+					print "Your CPU is affected, ";
+					if (hex($microcoderev) >= 0xb9) {
+						print "but your microcode is new enough\n";
+					} elsif ($hyperthreading ne "on") {
+						print "but hyper threading is off, which works around the problem\n";
+					} else {
+						print "you should install the latest intel-microcode\n";
+					}
+				} else {
+					print "You may need a BIOS/UEFI update (unknown Skylake-Y/H/U/S stepping)\n";
+				}
+			} elsif ($model == 85 or $model == 142 or $model == 158) {
+				print "You may need a BIOS/UEFI update (Kaby Lake, or Skylake-X processor)\n";
+			} else {
+				print "You're likely not affected\n";
+			}
+		} else {
+			print "You're not affected\n";
+		}
+
+		$cpunum = undef;
+		$vendor = undef;
+		$family = undef;
+		$stepping = undef;
+		$microcoderev = undef;
+		$hyperthreading = undef;
+
+		next;
+	}
+
+	$cpunum = $1 if /^processor\s*:\s(.*)/;
+	$vendor = $1 if /^vendor_id\s*:\s(.*)/;
+	$family = $1 if /^cpu family\s*:\s(.*)/;
+	$model = $1 if /^model\s*:\s(.*)/;
+	$stepping = $1 if /^stepping\s*:\s(.*)/;
+	$microcoderev = $1 if /^microcode\s*:\s(.*)/;
+
+	if (/^flags\s*:/) {
+		if (/^flags\s*:.*\bht\b/) {
+			$hyperthreading = "on";
+		} else {
+			$hyperthreading = "off";
+		}
+	}
+}
+