Reference to non-existing CONFIG_X86_FEATURE_CALL_DEPTH

[Lukas Bulwahn]

Dear Thomas, dear Peter,

in your work on call depth tracking mitigation, commit 5d8213864ade
("x86/retbleed: Add SKL return thunk") on linux-next references the
configuration symbol CONFIG_X86_FEATURE_CALL_DEPTH, which is not
introduced in any Kconfig file.

Is this just some left-over from some previous iteration of this
feature or is there still a patch to come that will introduce that
configuration symbol in some Kconfig file?

This issue was identified with ./scripts/checkkconfigsymbols.py.


Best regards,

Lukas