79 lines · bash
1#!/usr/bin/env bash2 3set -euo pipefail4 5TIMEOUT=106 7function do_one8{9 local mitigation="$1"10 local orig11 local start12 local now13 14 orig=$(cat "$mitigation")15 16 start=$(date +%s)17 now=$start18 19 while [[ $((now-start)) -lt "$TIMEOUT" ]]20 do21 echo 0 > "$mitigation"22 echo 1 > "$mitigation"23 24 now=$(date +%s)25 done26 27 echo "$orig" > "$mitigation"28}29 30rc=031cd /sys/kernel/debug/powerpc || rc=132if [[ "$rc" -ne 0 ]]; then33 echo "Error: couldn't cd to /sys/kernel/debug/powerpc" >&234 exit 135fi36 37tainted=$(cat /proc/sys/kernel/tainted)38if [[ "$tainted" -ne 0 ]]; then39 echo "Error: kernel already tainted!" >&240 exit 141fi42 43mitigations="barrier_nospec stf_barrier count_cache_flush rfi_flush entry_flush uaccess_flush"44 45for m in $mitigations46do47 if [[ -f /sys/kernel/debug/powerpc/$m ]]48 then49 do_one "$m" &50 fi51done52 53echo "Spawned threads enabling/disabling mitigations ..."54 55if stress-ng > /dev/null 2>&1; then56 stress="stress-ng"57elif stress > /dev/null 2>&1; then58 stress="stress"59else60 stress=""61fi62 63if [[ -n "$stress" ]]; then64 "$stress" -m "$(nproc)" -t "$TIMEOUT" &65 echo "Spawned VM stressors ..."66fi67 68echo "Waiting for timeout ..."69wait70 71tainted=$(cat /proc/sys/kernel/tainted)72if [[ "$tainted" -ne 0 ]]; then73 echo "Error: kernel became tainted!" >&274 exit 175fi76 77echo "OK"78exit 079