module param for CPU_NOTIFIER_ERROR_INJECT

hello,
I am playing around with CPU_NOTIFIER_ERROR_INJECT and am noticing that

example 2

# modprobe cpu-notifier-error-inject cpu_up_prepare_error=-2
# echo 1 > /sys/devices/system/cpu/cpu1/online
bash: echo: write error: No such file or directory

is not working for me, or atleast is not showing me any info that it is working.

the other proceedure does work:

example 1

# modprobe cpu-notifier-error-inject cpu_down_prepare_error=-1
# echo 0 > /sys/devices/system/cpu/cpu1/online
bash: echo: write error: Operation not permitted

dmesg shows:

[ 2427.924405] Injecting error (-1) at cpu notifier
[ 2427.930569] _cpu_down: attempt to take down CPU 1 failed

any ideas on what I need to do or is this working, and am I not seeing anything in dmesg?

Justin P. Mattock

2011/8/22 Justin P. Mattock <[email protected]>:

I suspect that cpu-notifier-error-inject module is already loaded and the module parameter is just ignored when you run above commands.

Please retry it after rmmod or change that parameter through /sys/module/cpu-error-inject/parameters/cpu_up_prepare_error.

cool, Thanks for the help.. not sure if this is correct, but I had to shutdown one of the cores, then execute the cammand to get any response..:

echo 0 > /sys/devices/system/cpu/cpu1/online modprobe cpu-notifier-error-inject cpu_up_prepare_error=-2 echo 1 > /sys/devices/system/cpu/cpu1/online

[ 4205.955592] Injecting error (-2) at cpu notifier
[ 4205.955601] _cpu_up: attempt to bring up CPU 1 failed

so it is working!

Justin P. Mattock