From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793399399; b=N5mle2nkR9aCIx4Dta3Bvgi354nw0py+p/qszGA1qQ9QqXQh15bUd3wlJcipWj0aJ0gq E4738R/31r7iZRGIjs6b36v5H2uG0sbERjP7VnJxWSLh6RuBDWI1ALg1scdJFWsbTDfp6 x5SH2W6PQil8hrLtL5sYKSphrI5LGfYNuoMP6VBss7RfzpHGNoSVuWLZWmY77n7uCnj6K 7OwmWUggonSgOncUkEWd/DzqkoinBPUHBndzHUV84EeTHGltfMkQyx9ge/NCxDjaQJxl1 vxDPMcASCdjJyXLqAyakAi0l+ZLvILgKDMgW0R8aIsDtgraaMm4TH9BA9YTv26L6jgQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793399399; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=aSkk09/yktJ+E/or+xyblvOstjgnyc2a5E9M6YN6VME=; b=obDKNrEuUQUy9/FSgbTIlejjYMlmwN5yCG7kFwrY2U4gZkV5yy3BdsWk7Ya+ecsL2Oa3 WYRNmOffdbKdP/NtYpkzxzBnewrj3nYVsFOA6gPXuWgUZ1o/3Mo9yZcnEK3Ie4QCWdVqP HCVQtCuvucA59OiRqtkzXW1eEd+ZNUVXnvGzSgCPziD3yhqXrtriitRexEsw8uCr9x8Ri aZQ0rbeuNP85yGjBC0EfjyAUkVmHB6bkDWyGm3AldxflKGa9d5emijYmLHmwFJzuqI/sF ukMoP1F3ONWl3kfXPf2wZkVhBjniY8KRG3JkmmYQOEzUYZhrQYApDiQbT64nedbSPdA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=RtBzDAft; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 346A9606A31A; Fri, 30 Oct 2026 22:29:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=RtBzDAft Received: by smtp.kernel.org (Postfix) with ESMTPSA id 026931F0093A; Fri, 30 Oct 2026 22:29:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793399399; bh=aSkk09/yktJ+E/or+xyblvOstjgnyc2a5E9M6YN6VME=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=RtBzDAftLyTiCB+s6T9O9f+u3CAcRFnr10MXb9DzJ5uWDLheTgqJlCsSLGJN2SzRB R8igDMHThaWXXvTzlNcrPM2I27DjlcEXfSbJvdFMSo0RCh8TqxW8JQjEbLgNFv1lET IgYRiPFEocjgrFPIUQh5k1I+X5wmB5xx3zlP2dF5iGfmKi1QoiIVLezo9PV/uSAkip HaJyuKFZSo9wsiymImiHOeUxCkwz80Wnb30FqoWkwbLvAo3pfucBtPCH6Jjs22e9SI 1piJDPwscdARR9cgJEqJ25AwjPky0+Ik8QrMpb8Ry3bDCTGYoVZN+VG0q6xdKfKqbd lZsh+sm7B47oA== Date: Fri, 30 Oct 2026 15:29:58 -0700 From: Kees Cook To: Nathan Chancellor Cc: Nicolas Schier , Julian Braha , "Lorenzo Stoakes (ARM)" , linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, Ricardo Ribalda , linux-s390@vger.kernel.org Subject: Re: [PATCH 1/2] kbuild: Move testing of '-mfentry' back to Makefile from Kconfig Message-ID: <20261030222934.0fcfa7-kees@kernel.org> References: <20261020-kconfig-fix-mfentry-check-v1-0-428258bc0fc0@kernel.org> <20261020-kconfig-fix-mfentry-check-v1-1-428258bc0fc0@kernel.org> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261020-kconfig-fix-mfentry-check-v1-1-428258bc0fc0@kernel.org> On Tue, Oct 20, 2026 at 02:52:18PM -0700, Nathan Chancellor wrote: > Ricardo reported another issue with moving this check from Kbuild to > Kconfig, as '-mfentry' is not supported for x86_32 without '-fno-pic', > which affects GCC builds that are configured with PIE enabled by > default. arch/x86/Makefile adds '-fno-pic' to KBUILD_CFLAGS, so this > works properly in Kbuild. FWIW, Debian's i686-linux-gnu-gcc 16.2.0 hits this too: ARCH=i386 allmodconfig fails at scripts/mod/empty.o with "'-pg' without '-mfentry' may be unreliable with shrink wrapping" under -Werror. With this patch on top of Linus's tree, the whole build is clean. Tested-by: Kees Cook -- Kees Cook