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A script that determines what your course of action should be with the newly discovered HyperThreading bug.
#!/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.
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";
}
}
}
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