From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 28FC012E1C6; Tue, 4 Jun 2024 14:29:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717511390; cv=none; b=bjHws1ApojPWOjbeTQfCQnsB9zvPR/hwlKEQn34EXyLjnzJU6u2y4ZfxMke1e9J6eAsGGVsXJcYnJV3iSkIn00T/R6Nh8woWpGFFwmb0VO8xpGks7i6edWPJ2aQMFx9ahnfco+eBJgXYeP2cshTKWP1pMoB9XwvhnS8wqzDe+/U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717511390; c=relaxed/simple; bh=RYVqR2gATEQ+i8NFnZGN6b5inLIzZ2bALRV5omE/pto=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=tVj6HpWuQ8S2NzyoFmHuSEYC9iXsH/uq/14M3GtVfUJl7u+sDZQeJmFCaCyo5TiQ73bpVmmzlskjngi5B/Q4lwRs2FpwPZ3L4stwBjZtDvT6+NIrZvT9SUKZFZY2f2gZwEQ0wSgBW9yjwspHuowikvSAnoQ6Ghw8OmiwEuT4DOg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LMQxkxwI; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LMQxkxwI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E945BC32786; Tue, 4 Jun 2024 14:29:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1717511389; bh=RYVqR2gATEQ+i8NFnZGN6b5inLIzZ2bALRV5omE/pto=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LMQxkxwItHEyc0tuHD46Cq6ZIFnI2PqRgcPo/rHiZxmQYoXWcW+z8Me6WqY4UTpfD p5xGiufhACSdpulwIDjc0ROPASwruHfmhvDGJrlbuQ5SU9meMtvwCAl8OarGE6bd2+ gfxwVfJUUAu3EUroDavLsd7BdRTR054oPF8jtuyDlOw62e8zeX2Bgahp+BimJ5102H lOcSUeEF88Y0hF+lR1V4e+KgswypSX6qb6On8mHFA4JOrX2mej4kbhWlLfQn1HcG/d 5IwUiGDgxSpr/+hxtVtgubCv1WC1s6TgLE4dthl42VVGbfAw3hKjoekzIXTrM1q8Ht QxMsW4NONw73w== Date: Tue, 4 Jun 2024 15:29:41 +0100 From: Will Deacon To: Alice Ryhl Cc: Jamie.Cunliffe@arm.com, a.hindborg@samsung.com, alex.gaynor@gmail.com, ardb@kernel.org, benno.lossin@proton.me, bjorn3_gh@protonmail.com, boqun.feng@gmail.com, broonie@kernel.org, catalin.marinas@arm.com, gary@garyguo.net, keescook@chromium.org, kernel@valentinobst.de, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, mark.rutland@arm.com, masahiroy@kernel.org, maz@kernel.org, miguel.ojeda.sandonis@gmail.com, nathan@kernel.org, ndesaulniers@google.com, nicolas@fjasle.eu, ojeda@kernel.org, rust-for-linux@vger.kernel.org, samitolvanen@google.com, wedsonaf@gmail.com Subject: Re: [PATCH v2] rust: add flags for shadow call stack sanitizer Message-ID: <20240604142941.GD20384@willie-the-truck> References: <20240409103120.GA22557@willie-the-truck> <20240430110925.1064685-1-aliceryhl@google.com> Precedence: bulk X-Mailing-List: linux-kbuild@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240430110925.1064685-1-aliceryhl@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) On Tue, Apr 30, 2024 at 11:09:25AM +0000, Alice Ryhl wrote: > Will Deacon wrote: > > On Tue, Mar 05, 2024 at 01:14:19PM +0100, Miguel Ojeda wrote: > >> Otherwise partially reverting to the `target.json` approach sounds good too. > >> > >> I added the `-Zuse-sync-unwind=n` to the list at > >> https://github.com/Rust-for-Linux/linux/issues/2. Given the default is > >> what we want, I have put it in the "Good to have" section. > > > > I think we have time to do this properly, like we did for the clang > > enablement a few years ago. In hindsight, avoiding hacks for the early > > toolchains back then was a really good idea because it meant we could > > rely on a solid baseline set of compiler features from the start. > > > > So, please can we fix this in rustc and just have SCS dependent on that? > > Just to keep you in the loop, I've posted a PR to make rustc recognize > the reserve-x18 target feature, so that the -Ctarget-feature=+reserve-x18 > flag stops emitting a warning. > > This should be sufficient for adding support for CONFIG_DYNAMIC_SCS. > > You can find it here: > https://github.com/rust-lang/rust/pull/124323 > > As for non-dynamic SCS, I plan to tackle that after the PR is merged. > See the "Future possibilities" section in the linked PR for more info on > that. Thanks for persevering with this, Alice. I read the pull request above, but it looks like you went with: https://github.com/rust-lang/rust/pull/124655 instead, which was merged (hurrah!). Do we need anything else? Will