On Wed, Feb 3, 2016 at 10:58 AM, Ulf Hansson <ulf.hans...@linaro.org> wrote: > On 30 January 2016 at 12:54, Rafael J. Wysocki <r...@rjwysocki.net> wrote: >> From: Rafael J. Wysocki <rafael.j.wyso...@intel.com> >> >> There is a WARN_ON() in dev_pm_domain_set() that triggers on attempts >> to set the pm_domain pointer for devices with a driver bound. >> >> However, that WARN_ON() triggers on attempts to clear the pointer >> too and the test it uses is based on checking the device's >> p->knode_driver pointer which still is set when the device bus >> type's/driver's ->remove callback has been executed. This >> leads to false-positive warnings when bus type code calls >> dev_pm_domain_set() to clear the pm_domain pointer after >> invoking the driver's ->remove() callback. >> >> To avoid those false-positives, make dev_pm_domain_set() check >> if the pointer passed to it is NULL and skip the warning in >> that case. >> >> Fixes: 989561de9b51 (PM / Domains: add setter for dev.pm_domain) >> Signed-off-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com> >> --- >> drivers/base/power/common.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> Index: linux-pm/drivers/base/power/common.c >> =================================================================== >> --- linux-pm.orig/drivers/base/power/common.c >> +++ linux-pm/drivers/base/power/common.c >> @@ -146,7 +146,7 @@ void dev_pm_domain_set(struct device *de >> if (dev->pm_domain == pd) >> return; >> >> - WARN(device_is_bound(dev), >> + WARN(pd && device_is_bound(dev), >> "PM domains can only be changed for unbound devices\n"); > > Perhaps this information then becomes a bit misleading, as it's okay > to clear the pointer, but not assign it to a valid PM domain.
Well, this is a "you're doing a wrong thing" warning and it does say what the wrong thing is. Does it have to be more specific? I don't think so. Thanks, Rafael
