> On 7/8/22 11:30 AM, Jose E. Marchesi via Gcc-patches wrote: >> >> The kernel bpftool expects BTF_KIND_FUNC entries in BTF to include an >> annotation reflecting the linkage of functions (static, global). For >> whatever reason they (ab)use the `vlen' field of the BTF_KIND_FUNC entry >> instead of adding a variable-part to the record like it is done with >> other entry kinds. >> > > For BTF Variables, we have the linkage information in the output > section as "btv_linkage". To propagate that information from DWARF to > BTF, we have the dvd_visibility in struct ctf_dvdef (in ctfc.h). Now > that the linkage information is needed for the BTF_KIND_FUNC entries, > what do you think about - adding something like dtd_visibility to > ctf_dtdef. > > Updating the BTF format documentation will be useful > https://www.kernel.org/doc/Documentation/bpf/btf.rst. Let's see what > can be done for that... > > Also, adding some testcases with the current patch will be great. > > I have created PR debug/106263 "BTF_KIND_FUNC type does not encode > linkage" to track this.
Sending V2 with the requested changes.
