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Date:   Mon, 25 Oct 2021 11:04:33 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Rob Landley <rob@landley.net>
Cc:     Josh Poimboeuf <jpoimboe@redhat.com>,
        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.
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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.

We have too damn many daft configurations as is.