Re: [PATCH V2 9/9] x86/speculation: Remove all ANNOTATE_NOSPEC_ALTERNATIVE directives

From: Alexandre Chartre
Date: Tue Apr 07 2020 - 10:28:32 EST



On 4/7/20 3:34 PM, Josh Poimboeuf wrote:
On Tue, Apr 07, 2020 at 03:28:37PM +0200, Peter Zijlstra wrote:
Josh, we should probably have objtool verify it doesn't emit ORC entries
in alternative ranges.

Agreed, it might be as simple as checking for insn->alt_group in the
INSN_STACK check or in update_insn_state().


We could do that only for the "objtool orc generate" command. That way
"objtool check" would still check the alternative, but "objtool orc generate"
will just use the first half of the alternative (like it does today with
ANNOTATE_NOSPEC_ALTERNATIVE). We can even keep all ANNOTATE_NOSPEC_ALTERNATIVE
but only use them for "objtool orc generate".

alex.