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Date: Tue, 4 Feb 2025 07:10:00 -0800
From: Kees Cook <kees@kernel.org>
To: Thomas =?iso-8859-1?Q?Wei=DFschuh?= <thomas.weissschuh@linutronix.de>
Cc: Eric Biederman <ebiederm@xmission.com>, Shuah Khan <shuah@kernel.org>,
	Nathan Chancellor <nathan@kernel.org>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Bill Wendling <morbo@google.com>,
	Justin Stitt <justinstitt@google.com>,
	Andy Lutomirski <luto@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Vincenzo Frascino <vincenzo.frascino@arm.com>, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
	llvm@lists.linux.dev
Subject: Re: [PATCH 04/16] elf, uapi: Add definitions for VER_FLG_BASE and
 VER_FLG_WEAK
Message-ID: <202502040708.6E9CF77@keescook>
References: <20250203-parse_vdso-nolibc-v1-0-9cb6268d77be@linutronix.de>
 <20250203-parse_vdso-nolibc-v1-4-9cb6268d77be@linutronix.de>
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In-Reply-To: <20250203-parse_vdso-nolibc-v1-4-9cb6268d77be@linutronix.de>

On Mon, Feb 03, 2025 at 10:05:05AM +0100, Thomas Weißschuh wrote:
> The definitions are used by tools/testing/selftests/vDSO/parse_vdso.c.
> To be able to build the vDSO selftests without a libc dependency,
> add the definitions to the kernels own UAPI headers.

For all the UAPI changes, where are the defines "normally" found? i.e.
how does adding these to UAPI not break something that already has them?
Or have these never been defined before? I'm confused about how removing
the libc dependency exposes the lack of these defines. Are they defined
in a non-exported libc header somewhere?

-Kees

-- 
Kees Cook