On Wed, May 18, 2016 at 1:34 PM, Rafael J. Wysocki <raf...@kernel.org> wrote: > On Wed, May 18, 2016 at 8:07 AM, Lianwei Wang <lianwei.w...@gmail.com> wrote: >> This makes pm notifier PREPARE/POST symmetrical: if PREPARE >> fails, we will only undo what ever happened on PREPARE. >> >> It fixes the unbalanced cpu hotplug enable in cpu pm notifier. > > Can you please describe the problem you're trying to address in a bit > more detail?
It is described in another patch, and it is a common issue. I fixed the similar issue several times, all because that the CPU_POST_SUSPEND notifier callback is called without call CPU_SUSPEND_PREPARE notifier callback before. Something is DO in PM_XXX_PREPARE and UNDO in POST_XXX. If we don't DO it in XXX_PREPARE then we don't need to UNDO it in PM_POST_XXX. Here is the link for the unbalanced cpu hotplug enable case: https://lkml.org/lkml/2016/5/6/61 . Thanks, Lianwei
