On Mon, Mar 14, 2022 at 12:19:41PM +0100, Michal Koutný wrote: > Hello. > > In my opinion there are two approaches: > a) drop this backport (given other races present), I have no problem with that, want to send a revert patch? > b) swap the locks compatible with v4.19 as this patch proposes. > > On Mon, Mar 14, 2022 at 05:11:50PM +0800, Zhang Qiao <zhangqiao22@xxxxxxxxxx> wrote: > > + /* > > + * It should hold cpus lock because a cpu offline event can > > + * cause set_cpus_allowed_ptr() failed. > > + */ > > + cpus_read_lock(); > > Maybe just a nit, the old kernels before commit c5c63b9a6a2e ("cgroup: > Replace deprecated CPU-hotplug functions.") v5.15-rc1~159^2~5 > would be more consistent with get_online_cpus() here (but they're > equivalent functionally so the locking order is correct). A fixed up patch would also be appreciated :) thanks, greg k-h