linux - How to disable/enable cpu cores *without* root access -


i have been trying disable or enable 1 or more cpu cores in linux machine using 

sudo sh -c "echo 'n' > /sys/devices/system/cpu/cpu1/online"

just thinking if there way out there same no root access. thanks

you can use setuid http://www.linuxnix.com/2011/12/suid-set-suid-linuxunix.html

however, setuid disabled security reasons bash scripts, can write program, maybe in c, symply calls

system("echo 'n' > /sys/devices/system/cpu/cpu1/online");

name executable stopcpu, following

chmod a+x stopcpu sudo chown root stopcpu sudo chmod u+s stopcpu

from moment, ./stopcpu run root permissions without having put root password, , valid file only.


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