On Wed, Feb 15, 2023 at 06:50:19PM +0200, Laurent Pinchart wrote: > Several drivers call subdev pad operations, passing structures that are > not fully zeroed. While the drivers initialize the fields they care > about explicitly, this results in reserved fields having uninitialized > values. Future kernel API changes that make use of those fields thus > risk breaking proper driver operation in ways that could be hard to > detect. > > To avoid this, make the code more robust by zero-initializing all the > structures passed to subdev pad operation. Maintain a consistent coding > style by preferring designated initializers (which zero-initialize all > the fields that are not specified) over memset() where possible, and > make variable declarations local to inner scopes where applicable. One > notable exception to this rule is in the ipu3 driver, where a memset() > is needed as the structure is not a local variable but a function > parameter provided by the caller. > > Not all fields of those structures can be initialized when declaring the > variables, as the values for those fields are computed later in the > code. Initialize the 'which' field in all cases, and other fields when > the variable declaration is so close to the v4l2_subdev_call() call that > it keeps all the context easily visible when reading the code, to avoid > hindering readability. > > Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > --- [...] > drivers/staging/media/imx/imx-media-capture.c | 28 ++++++++++-------- Reviewed-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> regards Philipp
