Hi Shivank, On Tue, 20 Aug 2024 at 11:52, Shivank Garg <shivankg@xxxxxxx> wrote: > > .pushsection .noinstr.text, "ax" > SYM_CODE_START(fill_return_buffer) > + UNWIND_HINT_FUNC > __FILL_RETURN_BUFFER(%_ASM_AX,RSB_CLEAR_LOOPS) > RET > SYM_CODE_END(fill_return_buffer) > +__EXPORT_THUNK(fill_return_buffer) > .popsection Thanks a lot for the pointer! UNWIND_HINT_FUNC does indeed seem to be what I was missing with the objtool warning. Regarding the build failure, could you share your config/toolchain info so I can try to reproduce? Would be handy for checking my next posting. Now I see your mail, it seems surprising that it compiles for me. Also while I'm replying to this thread I'll note this: > + if (!IS_ENABLED(CONFIG_RETPOLINE) || > + !cpu_feature_enabled(X86_FEATURE_RSB_VMEXIT)) It's called CONFIG_MITIGATION_RETPOLINE now. And furthermore, kvm_get_running_vcpu needs to be noinstr, I'm getting an objtool warning about this that wasn't mentioned in my cover letter.
