Re: [PATCH v4.4 STABLE] PM / Domains: defer setting dev->pm_domain until genpd->attach_dev succeeds if present

[Greg KH <gregkh@linuxfoundation.org>]

On Wed, Jul 26, 2017 at 11:07:35AM +0100, Sudeep Holla wrote:
> commit 975e83cfb8dc16e7a2fdc58188c77c0c605876c2 upstream.
> 
> If the genpd->attach_dev or genpd->power_on fails, genpd_dev_pm_attach
> may return -EPROBE_DEFER initially. However genpd_alloc_dev_data sets
> the PM domain for the device unconditionally.
> 
> When subsequent attempts are made to call genpd_dev_pm_attach, it may
> return -EEXISTS checking dev->pm_domain without re-attempting to call
> attach_dev or power_on.
> 
> platform_drv_probe then attempts to call drv->probe as the return value
> -EEXIST != -EPROBE_DEFER, which may end up in a situation where the
> device is accessed without it's power domain switched on.
> 
> Fixes: f104e1e5ef57 (PM / Domains: Re-order initialization of generic_pm_domain_data)
> Cc: 4.4+ <stable@vger.kernel.org> # v4.4+
> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
> Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> ---
>  drivers/base/power/domain.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)

Now applied, thanks.

greg k-h