From patchwork Wed Nov 8 02:26:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Maurer X-Patchwork-Id: 13449525 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 72F19A4F for ; Wed, 8 Nov 2023 02:27:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="sCmUhvrN" Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E5D8F10F8 for ; Tue, 7 Nov 2023 18:27:54 -0800 (PST) Received: by mail-yb1-xb49.google.com with SMTP id 3f1490d57ef6-da04776a869so6504166276.0 for ; Tue, 07 Nov 2023 18:27:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1699410474; x=1700015274; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=j+pXCzJsltO32Q6Q6QKytaM4r4O4ehr4GGX/b31TdaA=; b=sCmUhvrNpDzPvwfh8RXHn+9yWDq50A6xSMsWdxAJI7IiczvMBtv0jmW5ILjOzLbW5P Gw1dXMLJmyeUFBF23SORgYdvH8k2tg6IF7fr0oZk7oB2oADwupiVqg4ZwreU4UCCZpi3 vw3hkSdyklMFS+h21jiab7GCp5cuft82X8W+PJ3Th6GrhXKDi4T8nQe0+ESwGZurE6Ep kwX14C40DYRgu/QC28UQktSn7MiWKJETWqVyYRNNqJhXUcWAUCIVZ76vK8UoXwtVOSuQ pZ+FOy5DYKvDKTkakDE0wAfrwiIceAro0CGzULyIuDi4R4YeuXIJ3ixTsSoT+3Bmq/te CdUg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1699410474; x=1700015274; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=j+pXCzJsltO32Q6Q6QKytaM4r4O4ehr4GGX/b31TdaA=; b=lFGRD9kqpqZsrsWKa9LPZJh5idvs3r/hSiQqWlE6p/iCBQh3cmKWkinP9GYARXr00e 9N1vGkIU/UvoqnbIiABdhd94bHcTQC4IzYKHGWBxt63ieRYkAmisyrsIHHildhUVIPOn 7xHskrSLc9dKFyaOn9HM4DFjf6XcFLp42kZEO8enFSnOPOSVf5J2XKeSEUTkiSq4iJ2f 7PU0QDTxzf3UHHWVsbinjrqUUQt/81I3OKZCcdlhxa27LfPKY2bD9T0gESOlonx4jMV1 H/KYo9NYXlKuUeURmTNKblhW2eh6+bkLckNRSYqR1MHJsq6MjxQRL/8RnP5chUcKH/fK 4Ptg== X-Gm-Message-State: AOJu0YxuGNVgUzHPIeQusKRMftqi5QqE9GJoHgUVv64mEXB1N1hCzKzV h5z4rVlP4/btI7Rbq9GvO7OVvcYrvmHp X-Google-Smtp-Source: AGHT+IEStJ9CSqrdAUJC0EXXJkXE33qO2K7wb06zQcU3w37tWljEEI+W9gKdDO6RYrRaincap25EZASrHFME X-Received: from anyblade.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:1791]) (user=mmaurer job=sendgmr) by 2002:a05:6902:102:b0:da3:723b:b2a4 with SMTP id o2-20020a056902010200b00da3723bb2a4mr8048ybh.7.1699410474120; Tue, 07 Nov 2023 18:27:54 -0800 (PST) Date: Wed, 8 Nov 2023 02:26:25 +0000 In-Reply-To: <20231108022651.645950-2-mmaurer@google.com> Precedence: bulk X-Mailing-List: linux-modules@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20231108022651.645950-2-mmaurer@google.com> X-Mailer: git-send-email 2.42.0.869.gea05f2083d-goog Message-ID: <20231108022651.645950-6-mmaurer@google.com> Subject: [PATCH 3/3] rust: Require RUST_MODULES for module support From: Matthew Maurer To: Masahiro Yamada , Luis Chamberlain , Miguel Ojeda , Alex Gaynor , Wedson Almeida Filho , Andrew Morton , "Masami Hiramatsu (Google)" , "Paul E. McKenney" , John Ogness , Randy Dunlap , Matthew Maurer , Zhen Lei , Nhat Pham , Greg Kroah-Hartman , " =?utf-8?q?Marc_Aur?= =?utf-8?q?=C3=A8le_La_France?= " Cc: linux-kbuild@vger.kernel.org, Boqun Feng , Gary Guo , " =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= " , Benno Lossin , Andreas Hindborg , Alice Ryhl , Nick Desaulniers , linux-kernel@vger.kernel.org, linux-modules@vger.kernel.org, rust-for-linux@vger.kernel.org Currently, we don't support MODVERSIONS for Rust symbols. For users that want to use Rust in the kernel but for whom MODVERSIONS is required, this allows the use of built-in Rust code even with MODVERSIONS enabled. It may additionally allow code-size reduction by avoiding exporting symbols that won't be used without Rust modules. Signed-off-by: Matthew Maurer --- init/Kconfig | 21 +++++++++++++++++---- kernel/module/Kconfig | 1 + rust/exports.c | 4 ++++ 3 files changed, 22 insertions(+), 4 deletions(-) diff --git a/init/Kconfig b/init/Kconfig index 9ffb103fc927..6912dbbee3f1 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1885,7 +1885,6 @@ config RUST bool "Rust support" depends on HAVE_RUST depends on RUST_IS_AVAILABLE - depends on !MODVERSIONS depends on !GCC_PLUGINS depends on !RANDSTRUCT depends on !DEBUG_INFO_BTF || PAHOLE_HAS_LANG_EXCLUDE @@ -1896,13 +1895,27 @@ config RUST This allows other Rust-related options, like drivers written in Rust, to be selected. - It is also required to be able to load external kernel modules - written in Rust. - See Documentation/rust/ for more information. If unsure, say N. +config RUST_MODULES + bool "Rust Module Support" + depends on RUST + depends on MODULES + rust_modules + help + Enables support for Rust Modules in the kernel. + + This is required to load external kernel modules written in Rust. + + The two primary reasons to consider disabling this are: + * Allow MODVERSIONS support + * Allow additional code to be optimized out by the compiler if you + know that you'll only be using built-in Rust code. + + If unsure, say Y. + config RUSTC_VERSION_TEXT string depends on RUST diff --git a/kernel/module/Kconfig b/kernel/module/Kconfig index 0ea1b2970a23..a76128887618 100644 --- a/kernel/module/Kconfig +++ b/kernel/module/Kconfig @@ -158,6 +158,7 @@ config MODULE_UNLOAD_TAINT_TRACKING shown. If unsure, say N. config MODVERSIONS + depends on !RUST_MODULES bool "Module versioning support" help Usually, you have to use modules compiled with your kernel. diff --git a/rust/exports.c b/rust/exports.c index 83e2a7070cae..96b706048ed4 100644 --- a/rust/exports.c +++ b/rust/exports.c @@ -13,7 +13,11 @@ #include +#ifdef CONFIG_RUST_MODULES #define EXPORT_SYMBOL_RUST_GPL(sym) extern int sym; EXPORT_SYMBOL_GPL(sym) +#else +#define EXPORT_SYMBOL_RUST_GPL(sym) +#endif #include "exports_core_generated.h" #include "exports_alloc_generated.h"