On Monday, 18. June 2007, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rjw@xxxxxxx> > > At present, if a user mode helper is running while > usermodehelper_pm_callback() is executed, the helper may be frozen and the > completion in > call_usermodehelper_exec() won't be completed until user space processes > are thawed. As a result, the freezing of kernel threads may fail, which is > not desirable. > > Prevent this from happening by introducing a counter of running user mode > helpers and allowing usermodehelper_pm_callback() to succeed for > action = PM_HIBERNATION_PREPARE or action = PM_SUSPEND_PREPARE only if > there are no helpers running. [Namely, usermodehelper_pm_callback() waits > for at most RUNNING_HELPERS_TIMEOUT for the number of running helpers to > become zero and fails if that doesn't happen.] > > Special thanks to Uli Luckas <u.luckas@xxxxxxx> for reviewing the previous > versions of this patch and for very useful comments. > Acked-by: Uli Luckas <u.luckas@xxxxxxx> Regards, Uli -- ------- ROAD ...the handyPC Company - - - ) ) ) Uli Luckas Software Development ROAD GmbH Bennigsenstr. 14 | 12159 Berlin | Germany fon: +49 (30) 230069 - 64 | fax: +49 (30) 230069 - 69 url: www.road.de Amtsgericht Charlottenburg: HRB 96688 B Managing directors: Hans-Peter Constien, Hubertus von Streit _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
