Re: [PATCH v2] cgroup-v1: add disabled controller check in cgroup1_parse_param()

[chenzhou]

Hi Michal,

On 2021/1/14 21:12, Michal Koutný wrote:
> Hello Chen.
>
> On Fri, Dec 18, 2020 at 02:17:55PM +0800, Chen Zhou <chenzhou10@xxxxxxxxxx> wrote:
>> When mounting a cgroup hierarchy with disabled controller in cgroup v1,
>> all available controllers will be attached.
> Not sure if I understand the situation -- have you observed a v1
> controller attached to a hierarchy while specifying cgroup_no_v1= kernel
> cmdline arg?
Yeah, this is the situation.
In this case, at the beginning of function check_cgroupfs_options(), the mask
ctx->subsys_mask will be 0. And if we mount without 'none' and 'name=' options,
then in check_cgroupfs_options(), the flag ctx->all_ss will be set, that is, select all the subsystems.

Thanks,
Chen Zhou
>
> AFAICS, the disabled controllers are honored thanks to
> check_cgroupfs_options().
>
> Michal