Re: [PATCH v2 07/18] nitro_enclaves: Init misc device providing the ioctl interface

Paraschiv, Andra-Irina
2020-05-26T08:17:58Z

On 26/05/2020 09:42, Greg KH wrote:
> On Mon, May 25, 2020 at 11:49:50PM +0300, Paraschiv, Andra-Irina wrote:
>>
>> On 22/05/2020 10:07, Greg KH wrote:
>>> On Fri, May 22, 2020 at 09:29:35AM +0300, Andra Paraschiv wrote:
>>>> +static char *ne_cpus;
>>>> +module_param(ne_cpus, charp, 0644);
>>>> +MODULE_PARM_DESC(ne_cpus, "<cpu-list> - CPU pool used for Nitro Enclaves");
>>> This is not the 1990's, don't use module parameters if you can help it.
>>> Why is this needed, and where is it documented?
>> This is a CPU pool that can be set by the root user and that includes CPUs
>> set aside to be used for the enclave(s) setup; these CPUs are offlined. From
>> this CPU pool, the kernel logic chooses the CPUs that are set for the
>> created enclave(s).
>>
>> The cpu-list format is matching the same that is documented here:
>>
>> https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html
>>
>> I've also thought of having a sysfs entry for the setup of this enclave CPU
>> pool.
> Ok, but again, do not use a module parameter, they are hard to use,
> tough to document, and global. All things we moved away from a long
> time ago. Please use something else for this (sysfs, configfs, etc.)
> instead.

Alright, got it, will move on then with the other option for v4.

Thank you.

Andra