Jonathan, Nuno, I've sent RFC patch with trig->owner pointer initialization moval from register() to allocate() stage as Nuno suggested before: https://lore.kernel.org/linux-iio/20220601174837.20292-1-ddrokosov@xxxxxxxxxxxxxx/ Please review if possible and share your thoughts. On Wed, Jun 01, 2022 at 03:09:03PM +0200, Nuno Sá wrote: > On Wed, 2022-06-01 at 10:33 +0000, Dmitry Rokosov wrote: > > Hi Nuno, > > > > Thank you for comments! > > > > On Wed, Jun 01, 2022 at 10:47:54AM +0200, Nuno Sá wrote: > > > On Tue, 2022-05-31 at 18:57 +0000, Dmitry Rokosov wrote: > > > > Hi Jonathan, > > > > > > > > I have one question about a cases when trigger owner is builtin > > > > module. > > > > In the such cases trig->owner == null, because THIS_MODULE equals > > > > to > > > > null. How do you think, should we take into account such > > > > situations? > > > > > > > > IMHO we have to take in and save this information to trig_info > > > > during > > > > trigger allocation call. For example we can check THIS_MODULE > > > > from > > > > the > > > > > > Hmmm, If we were to do something during iio_trigger_alloc(), we > > > would > > > rather assign already THIS_MODULE to owner and we would not need > > > this > > > WARN(). I mean, if someone calls iio_trigger_get() before > > > allocating > > > it, it will have bigger problems :). > > > > > > > You are right, non-allocated pointer dereference is much bigger > > problem :) > > > > > I think this could actually be something reasonable... > > > > I think it could be a good solution, but it's required a lot of > > changes > > in the IIO drivers code, because if we assign trig->owner from > > iio_trigger_alloc(), we do not need this_mod parameter in the > > iio_trigger_register() iface and its wrappers. > > So it means to make it workable we must: > > - rework iio_trigger_alloc() > > - redesign iio_trigger_register() iface and its wrappers > > - correct iio_trigger_register() call from all IIO drivers > > > > I suppose we need to wait for Jonathan's comments here... > > > > I think we could actually get this done without having to change all > the drivers. Note on how iio_trigger_register() passes THIS_MODULE to > the internal API. We could also use macros in the alloc function in a > way that only internal functions would need to be changed. But it all > depends on whether or not Jonathan wants this moved... > > - Nuno Sá -- Thank you, Dmitry
