2018-07-12 10:55 GMT+02:00 Greg KH <gre...@linuxfoundation.org>: > On Thu, Jul 12, 2018 at 10:06:23AM +0200, Benjamin Gaignard wrote: >> In some cases the link between between customer and supplier >> already exist. Do not warn about already existing dependencies >> because device_link_add() take care of this case. > > Why would a link already exist that is asked to be created again? What > code path causes this?
It could happen that the link exist because a device use it parent as supplier. That case has been describe by Marek in this thread (I forgot to add it in the commit message, sorry): https://lkml.org/lkml/2018/7/9/356 > >> >> Reported-by: Marek Szyprowski <m.szyprow...@samsung.com> >> Signed-off-by: Benjamin Gaignard <benjamin.gaign...@st.com> >> --- >> drivers/base/core.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/base/core.c b/drivers/base/core.c >> index df3e1a44707a..fcdc17f0f349 100644 >> --- a/drivers/base/core.c >> +++ b/drivers/base/core.c >> @@ -105,7 +105,7 @@ static int device_is_dependent(struct device *dev, void >> *target) >> struct device_link *link; >> int ret; >> >> - if (WARN_ON(dev == target)) >> + if (dev == target) >> return 1; >> >> ret = device_for_each_child(dev, target, device_is_dependent); >> @@ -113,7 +113,7 @@ static int device_is_dependent(struct device *dev, void >> *target) >> return ret; >> >> list_for_each_entry(link, &dev->links.consumers, s_node) { >> - if (WARN_ON(link->consumer == target)) >> + if (link->consumer == target) >> return 1; > > Both of these WARN_ON are for valid code? That feels really odd to me, > I need more explanation here please. The documentation of the function is clear about return values: "Check if @target depends on @dev or any device dependent on it (its child or ts consumer etc). Return 1 if that is the case or 0 otherwise." so, for me, not need to warn user about something that is expected. Benjamin > > thanks, > > greg k-h
