On 18.01.2024 13:06, Michal Orzel wrote:
> At the moment, trying to run xencov read/reset (calling SYSCTL_coverage_op
> under the hood) results in a crash. This is due to an attempt to
> access code in the .init.* sections (libfdt for Arm and libelf for x86)
> that are stripped after boot. Normally, the build system compiles any
> *.init.o file without COV_FLAGS. However, these two libraries are
> handled differently as sections will be renamed to init after linking.
>
> This worked until e321576f4047 ("xen/build: start using if_changed")
> that added lib{fdt,elf}-temp.o to extra-y. Any file listed there without
> *.init.o suffix will be part of non-init-objects for which COV_FLAGS
> will be appended.
While this is true, aiui COV_FLAGS would be empty for anything listed
in nocov-y and all of the prerequisites of those objects (iirc target-
specific variable settings propagate to prerequisites). Therefore ...
> In such case, the solution is to add a file to nocov-y.
... libelf.o / libfdt.o already being listed there ought to suffice.
Alternatively listing only libelf-temp.o / libfdt-temp.o ought to
suffice as well.
Since you apparently observed things not working, I must be missing
something.
Jan
