On Mon, Aug 21, 2023 at 05:40:05PM +0200, Geert Uytterhoeven wrote: > Hi Andy, > > On Mon, Aug 21, 2023 at 5:25 PM Andy Shevchenko > <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote: > > On Mon, Aug 21, 2023 at 03:27:43PM +0200, Geert Uytterhoeven wrote: > > > On Mon, Aug 21, 2023 at 3:04 PM Andy Shevchenko > > > <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote: > > > > On Sun, Aug 20, 2023 at 07:44:00PM +0100, Biju Das wrote: > > > > ... > > > > > > For all your work likes this as I noted in the reply to Guenter that > > > > the couple of the selling points here are: > > > > 1) avoidance of the pointer abuse in OF table > > > > (we need that to be a valid pointer); > > > > > > There is no pointer abuse: both const void * (in e.g. of_device_id) > > > and kernel_ulong_t (in e.g. i2c_device_id) can be used by drivers > > > to store a magic cookie, being either a pointer, or an integer value. > > > The same is true for the various unsigned long and void * "driver_data" > > > fields in subsystem-specific driver structures. > > > > (void *)5 is the abuse of the pointer. > > We carry something which is not a valid pointer from kernel perspective. > > But the data field is not required to be a valid pointer. > What kind and type of information it represents is specific to the driver. > Exactly. Guenter
