On Sun, Jan 28, 2018 at 8:53 PM, <frowand.l...@gmail.com> wrote: > From: Frank Rowand <frank.row...@sony.com> > > Move duplicating and unflattening of an overlay flattened devicetree > (FDT) into the overlay application code. To accomplish this, > of_overlay_apply() is replaced by of_overlay_fdt_apply(). > > The copy of the FDT (aka "duplicate FDT") now belongs to devicetree > code, which is thus responsible for freeing the duplicate FDT. The > caller of of_overlay_fdt_apply() remains responsible for freeing the > original FDT. > > The unflattened device tree (aka expanded device tree, EDT) now
Not really a fan of a new acronym. > belongs to devicetree code, which is thus responsible for freeing > the EDT. > > These ownership changes prevent early freeing of the duplicated FDT > or the EDT, which could result in use after free errors. > > of_overlay_fdt_apply() is a private function for the anticipated > overlay loader. > > Update unittest.c to use of_overlay_fdt_apply() instead of > of_overlay_apply(). > > Move overlay fragments from artificial locations in > drivers/of/unittest-data/tests-overlay.dtsi into one devicetree > source file per overlay. This led to changes in > drivers/of/unitest-data/Makefile and drivers/of/unitest.c. Why the rearranging? That should be a separate patch. > > - Add overlay directives to the overlay devicetree source files so > that dtc will compile them as true overlays into one FDT data > chunk per overlay. For this? > - Set CFLAGS for drivers/of/unittest-data/testcases.dts so that > symbols will be generated for overlay resolution of overlays > that are no longer artificially contained in testcases.dts > > - Unflatten and apply each unittest overlay FDT using > of_overlay_fdt_apply(). > > - Enable the of_resolve_phandles() check for whether the overlay > EDT is detached. This check was previously disabled because the > overlays from tests-overlay.dtsi were not unflattened into detached > trees. > > - Other changes to unittest.c infrastructure to manage multiple test > FDTs built into the kernel image (access by name instead of > arbitrary number). > > - of_unittest_overlay_high_level(): previously unused code to add > properties from the overlay_base devicetree to the live tree > was triggered by the restructuring of tests-overlay.dtsi and thus > testcases.dts. This exposed two bugs: (1) the need to dup a > property before adding it, and (2) property 'name' is > auto-generated in the unflatten code and thus will be a duplicate > in the __symbols__ node - do not treat this duplicate as an error. > > Errors while developing the patch exposed inadequate error messages > to debug problems when overlay devicetree fragment nodes contain > an invalid target path. Improved the messages in find_target_node(). Sounds like another separate patch. Rob
