On Tue, May 14, 2024 at 09:25:55AM -0500, Lucas De Marchi wrote: > On Fri, May 10, 2024 at 10:57:22AM GMT, Jose Ignacio Tornos Martinez wrote: > > It has been seen that for some network mac drivers (i.e. lan78xx) the > > related module for the phy is loaded dynamically depending on the current > > hardware. In this case, the associated phy is read using mdio bus and then > > the associated phy module is loaded during runtime (kernel function > > phy_request_driver_module). However, no software dependency is defined, so > > the user tools will no be able to get this dependency. For example, if > > dracut is used and the hardware is present, lan78xx will be included but no > > phy module will be added, and in the next restart the device will not work > > from boot because no related phy will be found during initramfs stage. > > > > In order to solve this, we could define a normal 'pre' software dependency > > in lan78xx module with all the possible phy modules (there may be some), > > but proceeding in that way, all the possible phy modules would be loaded > > while only one is necessary. > > > > The idea is to create a new type of dependency, that we are going to call > > 'weak' to be used only by the user tools that need to detect this situation. > > In that way, for example, dracut could check the 'weak' dependency of the > > modules involved in order to install these dependencies in initramfs too. > > That is, for the commented lan78xx module, defining the 'weak' dependency > > with the possible phy modules list, only the necessary phy would be loaded > > on demand keeping the same behavior, but all the possible phy modules would > > be available from initramfs. > > > > The 'weak' dependency support has been included in kmod: > > https://github.com/kmod-project/kmod/commit/05828b4a6e9327a63ef94df544a042b5e9ce4fe7 > > But, take into account that this can only be used if depmod is new enough. > > If it isn't, depmod will have the same behavior as always (keeping backward > > compatibility) and the information for the 'weak' dependency will not be > > provided. > > > > Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@xxxxxxxxxx> > > > Reviewed-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx> Thanks! Applied and pushed to modules-next. Luis
