From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.zytor.com (terminus.zytor.com [198.137.202.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D192D41A8F; Wed, 9 Sep 2026 19:34:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.136 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788982449; cv=none; b=t+O2FbQ3bJJ+Jq8pstv/VlRyF8hxQhWFmsKsVu5g1LEXqcsw3pTe9BfzyLZyneRl7/4Av4LhTGxO3kwDrFLRPjS1YFzLdXzCaqXjtPuUTHuWhNXnWqEZmKhujB8IIy9N1zeZ3Vw5qQ+lidXRLoi0OQXXysVLozLPEX1UUKtK7K0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788982449; c=relaxed/simple; bh=t6WvPZKDUa+XIMc5MJIp9UjPq4fgZb3FxkTKoMvc1Bo=; h=Date:From:To:CC:Subject:In-Reply-To:References:Message-ID: MIME-Version:Content-Type; b=L/9BfTpBkMIpFe0Ovn38VkG3UXnfJeupZYhO6H+QjccorE2cpZfiOPg1kuDuc3mAeYljphkZ4r7sqqwDT7QLBE+Gbmty+/GWJNIFtDdh/ghHzhAPnfwC/WjDzXvHe6SCRg4tSKKEXPm3pmzBD3WyUc9hnwy1yqDu7IHTwzaylcw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zytor.com; spf=pass smtp.mailfrom=zytor.com; dkim=pass (2048-bit key) header.d=zytor.com header.i=@zytor.com header.b=gofX7hrQ; arc=none smtp.client-ip=198.137.202.136 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zytor.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=zytor.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=zytor.com header.i=@zytor.com header.b="gofX7hrQ" Received: from ehlo.thunderbird.net ([172.59.163.39]) (authenticated bits=0) by mail.zytor.com (8.18.1/8.17.1) with ESMTPSA id 689JW0Ri241996 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO); Wed, 9 Sep 2026 12:32:01 -0700 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.zytor.com 689JW0Ri241996 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2026082801; t=1788982324; bh=+dGDqKIiorLm4PMRWZf+lcjSymk+duftPVKL8h3BRa8=; h=Date:From:To:CC:Subject:In-Reply-To:References:From; b=gofX7hrQMbsXkfAGKbIB5EEVBWalAWuw926LqzLEOVYYNLyZUfbWEzWPGDLj9bbmQ WFie+ve7lUQ9pYuRVmVYjV+EqzzAArpgHRWshxY1qKfnMcxxPUBe/xs1MmeSmnGIOJ dPgyxNew5qsHsjhQOA41SlBB/MQHD0m+r1YFZE3wLCs3umtpLH2oSsE4iYDyt3+j/i rnjM7tEna8nBlg7YqDxC5Ptjf5+Rcrbt1/0XzPeibvb/+oRmhKO1xpHus1ynWSXLJ8 MI9bdFysgi5uqG5wVEpJJTL/7pSn2oMlC1a/K6We8WFSaRVoteYLUt+37PBgC/p1jC eVbxDJsilqYjA== Date: Wed, 09 Sep 2026 12:31:53 -0700 From: "H. Peter Anvin" To: Peter Zijlstra , =?ISO-8859-1?Q?Thomas_Wei=DFschuh?= CC: Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt , Andy Lutomirski , Vincenzo Frascino , Kees Cook , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Richard Weinberger , Anton Ivanov , Johannes Berg , Russell King , Catalin Marinas , Will Deacon , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Huacai Chen , WANG Xuerui , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Thomas Bogendoerfer , Miguel Ojeda , Alex Gaynor , Gary Guo , =?ISO-8859-1?Q?Bj=F6rn_Roy_Baron?= , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross , Danilo Krummrich , Thomas Gleixner , Christophe Leroy , Boqun Feng , Nicolas Schier , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, linux-mm@kvack.org, linux-um@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, loongarch@lists.linux.dev, linux-s390@vger.kernel.org, linux-mips@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-kbuild@vger.kernel.org, Jan Stancek , Arnaldo Carvalho de Melo , Alexandre Ghiti Subject: Re: [PATCH v5 12/24] vdso: Add the vdsocheck tool User-Agent: K-9 Mail for Android In-Reply-To: <20260908071911.GU4120091@noisy.programming.kicks-ass.net> References: <20260908-vdso-absolute-reloc-v5-0-3a93791af1cf@linutronix.de> <20260908-vdso-absolute-reloc-v5-12-3a93791af1cf@linutronix.de> <20260908071911.GU4120091@noisy.programming.kicks-ass.net> Message-ID: Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On September 8, 2026 12:19:11 AM PDT, Peter Zijlstra wrote: >On Tue, Sep 08, 2026 at 08:33:46AM +0200, Thomas Wei=C3=9Fschuh wrote: >> All vDSO code needs to be completely position independent=2E Symbol >> references are marked as hidden so the compiler emits PC-relative >> relocations=2E However there are cases where the compiler may still >> emit absolute relocations, as they are valid in regular PIC DSO code=2E >> These would be resolved by the linker and will break at runtime=2E >> This has been observed on arm64, see commit 0c314cda9325 ("arm64: vdso: >> Work around invalid absolute relocations from GCC") >>=20 >> Introduce a tool to check for absolute relocations during the build, >> as the current inline-shell logic is not expressive enough=2E >> The check is done on the object files as the relocations will not exist >> anymore in the final DSO=2E As there is no extension point for the >> compilation of each object file, perform the validation in vdso_check= =2E >>=20 >> Signed-off-by: Thomas Wei=C3=9Fschuh >> --- >> Makefile | 19 ++ >> lib/vdso/Kconfig | 5 + >> lib/vdso/Makefile | 2 + >> lib/vdso/Makefile=2Einclude | 14 ++ >> lib/vdso/check/=2Egitignore | 3 + >> lib/vdso/check/Makefile | 34 +++ >> lib/vdso/check/elf=2Ers | 498 ++++++++++++++++++++++++++++++++++= ++++++++++ >> lib/vdso/check/vdsocheck=2Ers | 154 ++++++++++++++ >> 8 files changed, 729 insertions(+) > >Urgh, does this mean I have to have rust installed just to build a >kernel now? It was going to happen, and now we'll have to suffer the instability of ru= st=2E=2E=2E