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Date:   Mon, 25 Oct 2021 07:46:56 -0700
From:   Josh Poimboeuf <jpoimboe@redhat.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Rob Landley <rob@landley.net>,
        Masahiro Yamada <masahiroy@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Andrii Nakryiko <andrii@kernel.org>
Subject: Re: Commit 0d989ac2c90b broke my x86-64 build.
Message-ID: <20211025144656.fqqneysf72wwxp3m@treble>
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On Mon, Oct 25, 2021 at 11:04:33AM +0200, Peter Zijlstra wrote:
> On Sun, Oct 24, 2021 at 09:51:45PM -0500, Rob Landley wrote:
> > > Unfortunately I think CONFIG_STACK_VALIDATION is no longer optional on
> > > x86-64 these days, because of static calls and retpolines.
> > 
> > Does it need stack validation, or just a frame unwinder?
> 
> static_calls rely on objtool to find all "call __SCT*" instructions and
> write their location in a .static_call_sites section.
> 
> The having of static calls is not optional on x86_64, and I have zero
> interest in trying to work out what not having static_call() does, or to
> maintain that option.

What I meant was, make STATIC_CALL_INLINE optional.  Then it would use
out-of-line static calls which should just work, no?

-- 
Josh