efi/libstub: Avoid linking libstub/lib-ksyms.o into vmlinux

drivers/firmware/efi/libstub/Makefile builds a static library, which
is not linked into the main vmlinux target in the ordinary way [arm64],
or at all [ARM, x86].

Since commit:

  7f2084fa55e6 ("[kbuild] handle exports in lib-y objects reliably")

any Makefile using lib-y generates lib-ksyms.o which is linked into vmlinux.

In this case, the following garbage object is linked into vmlinux.

  drivers/firmware/efi/libstub/lib-ksyms.o

We do not want to follow the default linking rules for static libraries
built under libstub/ so using subdir-y instead of obj-y is the correct
way to descend into this directory.

Signed-off-by: Masahiro Yamada <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>
[ardb: update commit log to clarify that arm64 deviates in this respect]
Signed-off-by: Ingo Molnar <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Link: https://lore.kernel.org/r/[email protected]

0 files changed, 0 insertions, 0 deletions