Re: [PATCH v3 00/39] x86: Kernel IBT

Peter Zijlstra
2022-03-04T20:22:56Z

On Fri, Mar 04, 2022 at 11:09:58AM -0800, Josh Poimboeuf wrote:

> I'm getting some warnings with CONFIG_X86_KERNEL_IBT=n:
>
> arch/x86/entry/entry_64.o: warning: objtool: irq_entries_start()+0x7: unreachable instruction
> arch/x86/kernel/ftrace_64.o: warning: objtool: return_to_handler()+0x2a: unreachable instruction

Urgh, lemme go chase that.

> And a warning with CONFIG_X86_KERNEL_IBT=y:
>
> vmlinux.o: warning: objtool: .text+0xaf0: unreachable instruction

This is that weak symbol issue :/ We talked about it on IRC, but i've
not yet come around to fixing it.

This is mostly a pre-existing issue, only uncovered because we run on
vmlinux more..