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 F32821F4626; Thu, 20 Feb 2025 12:14:06 +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=1740053648; cv=none; b=OGdvgp4CZqTiMkZyUodJ3hMsjOY6R2r21qORGaq8SSSBAN7ygV2LLOSznYxr5nTlP7vSEzLeVn3yYT+ynNTMXufOnN2y8cOMlpJIvFU39uS/LMGNJ3HMFG4PYpXNnTHExep5HHVP3nDX8ZPSY0ehSrI0MVyh67QEfnuT/hOwriI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740053648; c=relaxed/simple; bh=PtQW4VmpX3Gux2bL+ZFcWOaxQzQHWQuzF3wYCZ+6j/o=; h=Date:From:To:CC:Subject:In-Reply-To:References:Message-ID: MIME-Version:Content-Type; b=dOIFKMblmSq+W/o0jVuJnnsH4sk9hKlchHB+bdVucobk7zP/Ify+cykUT6sfEp8ctRSbrugMl6elEdEniXmLvmMr3DRSe3wR9Ibit6WpN/1fMIYIbhjK32Fi6sXZ10Md1URap+BAo7GI4z07rG5/cQWd9DrmMAsyeiXGp0xmVfs= 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=FT8HuSje; 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="FT8HuSje" Received: from [127.0.0.1] ([76.133.66.138]) (authenticated bits=0) by mail.zytor.com (8.18.1/8.17.1) with ESMTPSA id 51KCDxS02195213 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO); Thu, 20 Feb 2025 04:14:00 -0800 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.zytor.com 51KCDxS02195213 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2025021701; t=1740053640; bh=GhMAHSBtV9/kfMoKmY83r+p25mAz8E0HTxvLo+40ST8=; h=Date:From:To:CC:Subject:In-Reply-To:References:From; b=FT8HuSjeZC5A832cO6iAOgJF0qznA0PAd3qlSb34Zac6fWKZuEOdqOPRIyeVFqqw4 Ol5CBxY1NaPfJxNw+Lg6VNyPpIF7qG1RnxkJCNixDZwyxp44MMV+vWGomixexz8uFJ QEDZzqzcTLOoivbEgcNPl/hpG8kjxIDyFSFywdzpjbeqnQ+sQWy6aZ63qu2/Lrqqxs CmFqz+A9uOSyxGjkumLk4w719MSIEI0sIYKERzNtgpjTEiQg5jwXEmJD/GX9U51sNT kMlga5a/rWMNgeaITUxRp9vTg8q9lIR2YiT8V02jvnUMpAgv0jB+r4oN2qTreds3SU lUyXDI1ZQlKBQ== Date: Thu, 20 Feb 2025 04:13:59 -0800 From: "H. Peter Anvin" To: Alexey Dobriyan CC: Kees Cook , Miguel Ojeda , Christoph Hellwig , rust-for-linux , Linus Torvalds , Greg KH , David Airlie , linux-kernel@vger.kernel.org, ksummit@lists.linux.dev Subject: Re: Rust kernel policy User-Agent: K-9 Mail for Android In-Reply-To: <6E8DAA21-2CCE-4E53-A5A8-3B82D4A2334C@zytor.com> References: <202502191026.8B6FD47A1@keescook> <785A9F60-F687-41DE-A116-34E37F5B407A@zytor.com> <6E8DAA21-2CCE-4E53-A5A8-3B82D4A2334C@zytor.com> Message-ID: <1D187908-AA1B-4D17-A0AF-8672BE7476C2@zytor.com> Precedence: bulk X-Mailing-List: ksummit@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On February 20, 2025 4:01:28 AM PST, "H=2E Peter Anvin" w= rote: >On February 19, 2025 10:32:15 PM PST, Alexey Dobriyan wrote: >>On Wed, Feb 19, 2025 at 11:33:56AM -0800, H=2E Peter Anvin wrote: >>> b=2E Can we use existing mature tools, such as C++, to *immediately* i= mprove the quality (not just memory safety!) of our 37-year-old, 35-million= line code base and allow for further centralized improvements without the = major lag required for compiler extensions to be requested and implemented = in gcc (and clang) *and* dealing with the maturity issue? >> >>We can't and for technical reasons: >> >>* g++ requires C99 initializers to be in declaration order, >> even in cases where there is no reason to do so=2E >> >>* g++ doesn't support __seg_gs at all: >> >> $ echo -n -e 'int __seg_gs gs;' | g++ -xc++ - -S -o /dev/null >> :1:14: error: expected initializer before =E2=80=98gs=E2=80=99 >> >> x86 added this to improve codegen quality so this would be step backwa= rds=2E > >Ok, so those are obvious problems, and I agree that having to rely on the= legacy implementation of gs: is undesirable as anything than a transaction= crutch=2E > > Make that *transition* crutch=2E Stupid autocorrect=2E