Re: [PATCH] objtool: Fix SYSCALL instruction handling and INSN_CONTEXT_SWITCH

[Josh Poimboeuf]

On Fri, Apr 04, 2025 at 12:49:38PM +0200, Peter Zijlstra wrote:
> On Thu, Apr 03, 2025 at 11:48:13AM -0700, Josh Poimboeuf wrote:
> 
> > The real problem here is that INSN_CONTEXT_SWITCH is ambiguous.  It can
> > represent both call semantics (SYSCALL, SYSENTER) and return semantics
> > (SYSRET, IRET, RETS, RETU).  Those differ significantly: calls preserve
> > control flow whereas returns terminate it.
> 
> Does that not rather suggest we should perhaps have INSN_SYSCALL /
> INSN_SYSRET to replace the single ambiguous thing?

Is there any reason to have INSN_SYSCALL in the first place?

-- 
Josh