When 'exported twice' is warned, let sym_add_exported() return without updating the symbol info. This respects the previous export, which is ordered first in modules.order This simplifies the code too. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Now that there is no overwrap between symbols from ELF files and ones from Module.symvers. So, the 'exported twice' warning should be reported irrespective of where the symbol in question came from. The exceptional case is external module; in some cases, we build an external module to provide a different version/variant of the corresponding in-kernel module, overriding the same set of exported symbols. You can see this use-case in upstream; tools/testing/nvdimm/libnvdimm.ko replaces drivers/nvdimm/libnvdimm.ko in order to link it against mocked version of core kernel symbols. So, let's relax the 'exported twice' warning when building external modules. The multiple export from external modules is warned only when the previous one is from vmlinux or itself. With this refactoring, the ugly preloading goes away. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
It is complicated to add mocked-up symbols for pre-handling CRC. Handle CRC after all the export symbols in the relevant module are registered. Call handle_modversion() after the handle_symbol() iteration. In some cases, I see atand-alone __crc_* without __ksymtab_*. For example, ARCH=arm allyesconfig produces __crc_ccitt_veneer and __crc_itu_t_veneer. I guess they come from crc_ccitt, crc_itu_t, respectively. Since __*_veneer are auto-generated symbols, just ignore them. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This function handles not only modversions, but also unresolved symbols, export symbols, etc. Rename it to a more proper function name. While I was here, I also added the 'const' qualifier to *sym. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Currently, namespace_from_kstrtabns() relies on the fact that namespace strings are recorded in the __ksymtab_strings section. Actually, it is coded in include/linux/export.h, but modpost does not need to hard-code the section name. Elf_Sym::st_shndx holds the index of the relevant section. Using it is a more portable way to get the namespace string. Make namespace_from_kstrtabns() simply call sym_get_data(), and delete the info->ksymtab_strings . While I was here, I added more 'const' qualifiers to pointers. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
When CONFIG_MODULE_REL_CRCS is enabled, the value of __crc_* is not an absolute value, but the address to the CRC data embedded in the .rodata section. Getting the data pointed by the symbol value is somewhat complex. Split it out into a new helper, sym_get_data(). I will reuse it to refactor namespace_from_kstrtabns() in the next commit. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The local variable, ns_entry, is unneeded. While I was here, I also cleaned up the comparison with NULL or 0. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Matthias Maennich <maennich@google.com>
The modpost, with the -d option given, generates per-module .ns_deps files. Kbuild generates per-module .mod files to carry module information. This is convenient because Make handles multiple jobs in parallel when the -j option is given. On the other hand, the modpost always runs as a single thread. I do not see a strong reason to produce separate .ns_deps files. This commit changes the modpost to generate just one file, modules.nsdeps, each line of which has the following format: <module_name>: <list of missing namespaces> Please note it contains *missing* namespaces instead of required ones. So, modules.nsdeps is empty if the namespace dependency is all good. This will work more efficiently because spatch will no longer process already imported namespaces. I removed the '(if needed)' from the nsdeps log since spatch is invoked only when needed. This also solves the stale .ns_deps problem reported by Jessica Yu: https://lkml.org/lkml/2019/10/28/467 Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Tested-by: Jessica Yu <jeyu@kernel.org> Acked-by: Jessica Yu <jeyu@kernel.org> Reviewed-by: Matthias Maennich <maennich@google.com> Tested-by: Matthias Maennich <maennich@google.com>
buf_write() allocates memory. Free it. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
'make nsdeps' invokes the modpost three times at most; before linking vmlinux, before building modules, and finally for generating .ns_deps files. Running the modpost again and again is not efficient. The last two can be unified. When the -d option is given, the modpost still does the usual job, and in addition, generates .ns_deps files. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Tested-by: Matthias Maennich <maennich@google.com> Reviewed-by: Matthias Maennich <maennich@google.com>