Re: [PATCH RFC v1 2/3] Fix hibernation restore hang in freeze_processes

On Wed, Feb 19, 2014 at 9:52 AM, Sebastian Capella sebastian.capella@linaro.org wrote:

During restore, pm_notifier chain are called with PM_RESTORE_PREPARE. The firmware_class driver handler fw_pm_notify does not have a handler for this. As a result, it keeps a reader on the kmod.c umhelper_sem. During freeze_processes, the call to __usermodehelper_disable tries to take a write lock on this semaphore and hangs waiting.

Signed-off-by: Sebastian Capella sebastian.capella@linaro.org Cc: Russ Dill Russ.Dill@ti.com Cc: Ming Lei ming.lei@canonical.com Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org

Acked-by: Ming Lei ming.lei@canonical.com

Thanks, -- Ming Lei