feat: add FLUSH_CMD MSR availability detection (part of L1TF mitigation)

This commit is contained in:
Stéphane Lesimple 2018-08-16 19:05:09 +02:00
parent 339ad31757
commit dd67fd94d7
1 changed files with 36 additions and 0 deletions

View File

@ -1956,6 +1956,42 @@ check_cpu()
fi
fi
_info " * L1 data cache invalidation"
_info_nol " * FLUSH_CMD MSR is available: "
if [ ! -e /dev/cpu/0/msr ] && [ ! -e /dev/cpuctl0 ]; then
pstatus yellow UNKNOWN "is msr kernel module available?"
else
# the new MSR 'FLUSH_CMD' is at offset 0x10b, write-only
# we test if of all cpus
val=0
cpu_mismatch=0
for i in $(seq 0 "$idx_max_cpu")
do
write_msr 0x10b "$i"; ret=$?
if [ "$i" -eq 0 ]; then
val=$ret
else
if [ "$ret" -eq $val ]; then
continue
else
cpu_mismatch=1
fi
fi
done
if [ $val -eq 0 ]; then
if [ $cpu_mismatch -eq 0 ]; then
pstatus green YES
else
pstatus green YES "But not in all CPUs"
fi
elif [ $val -eq 200 ]; then
pstatus yellow UNKNOWN "is msr kernel module available?"
else
pstatus yellow NO
fi
fi
if is_intel; then
_info " * Enhanced IBRS (IBRS_ALL)"
_info_nol " * CPU indicates ARCH_CAPABILITIES MSR availability: "