From patchwork Wed Nov 25 01:05:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: William McVicker X-Patchwork-Id: 11930047 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, HK_RANDOM_FROM,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D1AD8C83017 for ; Wed, 25 Nov 2020 01:07:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9DB3B20DD4 for ; Wed, 25 Nov 2020 01:07:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="VD95qJ50" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728170AbgKYBGh (ORCPT ); Tue, 24 Nov 2020 20:06:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57336 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728124AbgKYBGg (ORCPT ); Tue, 24 Nov 2020 20:06:36 -0500 Received: from mail-qk1-x749.google.com (mail-qk1-x749.google.com [IPv6:2607:f8b0:4864:20::749]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 95992C0613D4 for ; Tue, 24 Nov 2020 17:06:36 -0800 (PST) Received: by mail-qk1-x749.google.com with SMTP id 202so552895qkl.9 for ; Tue, 24 Nov 2020 17:06:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=YbWKCne8oiSwCs+LETaaQuxj6nssPvd/ENx+h/xhUkQ=; b=VD95qJ50YfNhlAIzTqXB7bWZqflUREpGXlZ1v14Zqf7QbyEW+1fSYZQFDYq0wZCUPq rAGEUyIpaWJhNW7WYPua7SowPdY10PFtu23ICx45YcPyZN6CAChZIygSwekQjZc9hITx b921pHjRJc0DQeFHlQ7DmdXXkNGcQurJJ1u5b48tAydxKYJlniAmQMO26PzygE5BjMCS pbWDBeq5hPvR+M2TxrOohzEd4nAego3Zzt5WFie+KkF5uMivByps5K8U+lSh7SWLLLQm UYjfotcdqleoiDUby/Ebbetey+OkDgt8YEosMsDr6GZ2juZ0yX2jfKNEvX2tI7j5pVNB bu2w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=YbWKCne8oiSwCs+LETaaQuxj6nssPvd/ENx+h/xhUkQ=; b=XYZImKBoUPxynh/+wbtwNer+eSVFfCl39Y9xyFMj/vYQQcrBFYcrKp2BA/nu1rDKZ0 p4EmqXmIe8jkl7FwuHAkdpQry5rN35csYLdpXyvT7bVAFgTmxnfHOpyW7EUj3XAO8eo3 kvR5vVmiwXGf5IJECyiYcKjsPuxOy+6Xiu8dkbLuOgAWhUnDsGeJQ6K+jpNKBfT7THrK MIROzgtYfkqYpRBoELeNI3RzsJo5iEpmPaf8XafuDJwjYaVWUlB2u0iJJETPX/lJQhR4 ovuwHLsi7FgAeR6KADpH6IxihaJrFkcdqc9CMvjyotaa7E/r5pf7PSuz721BZJUJTLCg AzAw== X-Gm-Message-State: AOAM532l2GLK0wLH9txAVCUkbGyxB6P05s44lprtmsnqQ7g0Dcaa5X8l CFFuH0HG0yYFWeExIxDuzARWxdYItgRDmjbzZ10= X-Google-Smtp-Source: ABdhPJyiDeumgvZEcdU+MPnyD9qSO5ehrwZUtIoneyR5tx090S7hUOPBhUznUsNQpdC8NZ5a0FyxFRnByzqgPiusOKE= Sender: "willmcvicker via sendgmr" X-Received: from willmcvicker.c.googlers.com ([fda3:e722:ac3:10:24:72f4:c0a8:2dd0]) (user=willmcvicker job=sendgmr) by 2002:a0c:9e20:: with SMTP id p32mr1307270qve.44.1606266395772; Tue, 24 Nov 2020 17:06:35 -0800 (PST) Date: Wed, 25 Nov 2020 01:05:41 +0000 In-Reply-To: <20201125010541.309848-1-willmcvicker@google.com> Message-Id: <20201125010541.309848-3-willmcvicker@google.com> Mime-Version: 1.0 References: <20201125010541.309848-1-willmcvicker@google.com> X-Mailer: git-send-email 2.29.2.454.gaff20da3a2-goog Subject: [PATCH v2 2/2] modules: add scmversion field From: Will McVicker To: Jessica Yu , Masahiro Yamada , Michal Marek Cc: Greg Kroah-Hartman , Christoph Hellwig , Saravana Kannan , linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org, kernel-team@android.com, Will McVicker Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Add the modinfo field `scmversion` to include the SCM version of kernel modules, e.g. git sha1. This allows one to identify the exact source code version of a given kernel module. You can retrieve it in two ways, 1) By using modinfo > modinfo -F scmversion 2) By module sysfs node > cat /sys/module//scmversion Signed-off-by: Will McVicker --- Documentation/ABI/stable/sysfs-module | 17 +++++++++++++++++ include/linux/module.h | 1 + kernel/module.c | 2 ++ scripts/Makefile.modpost | 20 ++++++++++++++++++++ scripts/mod/modpost.c | 24 +++++++++++++++++++++++- 5 files changed, 63 insertions(+), 1 deletion(-) diff --git a/Documentation/ABI/stable/sysfs-module b/Documentation/ABI/stable/sysfs-module index 6272ae5fb366..46c99ec927ab 100644 --- a/Documentation/ABI/stable/sysfs-module +++ b/Documentation/ABI/stable/sysfs-module @@ -32,3 +32,20 @@ Description: Note: If the module is built into the kernel, or if the CONFIG_MODULE_UNLOAD kernel configuration value is not enabled, this file will not be present. + +What: /sys/module/MODULENAME/scmversion +Date: November 2020 +KernelVersion: 5.10 +Contact: Will McVicker +Description: This read-only file will appear if modpost was supplied with an + SCM version for the module. The SCM version is retrieved by + scripts/setlocalversion, which means that the presence of this + file depends on CONFIG_LOCALVERSION_AUTO=y or LOCALVERSION=. + When read, the SCM version that the module was compiled with is + returned. The SCM version is returned in the following format:: + + === + Git: g[a-f0-9]\+(-dirty)\? + Mercurial: hg[a-f0-9]\+(-dirty)\? + Subversion: svn[0-9]\+ + === diff --git a/include/linux/module.h b/include/linux/module.h index 6264617bab4d..63137ca5147b 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -372,6 +372,7 @@ struct module { struct module_attribute *modinfo_attrs; const char *version; const char *srcversion; + const char *scmversion; struct kobject *holders_dir; /* Exported symbols */ diff --git a/kernel/module.c b/kernel/module.c index a4fa44a652a7..a203dab4a03b 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -807,6 +807,7 @@ static struct module_attribute modinfo_##field = { \ MODINFO_ATTR(version); MODINFO_ATTR(srcversion); +MODINFO_ATTR(scmversion); static char last_unloaded_module[MODULE_NAME_LEN+1]; @@ -1269,6 +1270,7 @@ static struct module_attribute *modinfo_attrs[] = { &module_uevent, &modinfo_version, &modinfo_srcversion, + &modinfo_scmversion, &modinfo_initstate, &modinfo_coresize, &modinfo_initsize, diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index f54b6ac37ac2..fb4ddf2bf794 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -66,6 +66,7 @@ ifeq ($(KBUILD_EXTMOD),) input-symdump := vmlinux.symvers output-symdump := Module.symvers +module_srcpath := $(srctree) else @@ -77,6 +78,17 @@ src := $(obj) include $(if $(wildcard $(KBUILD_EXTMOD)/Kbuild), \ $(KBUILD_EXTMOD)/Kbuild, $(KBUILD_EXTMOD)/Makefile) +# Get the external module's source path. KBUILD_EXTMOD could either be an +# absolute path or relative path from $(srctree). This makes sure that we +# aren't using a relative path from a separate working directory (O= or +# KBUILD_OUTPUT) since that may not be the actual module's SCM project path. So +# check the path relative to $(srctree) first. +ifneq ($(realpath $(srctree)/$(KBUILD_EXTMOD) 2>/dev/null),) + module_srcpath := $(srctree)/$(KBUILD_EXTMOD) +else + module_srcpath := $(KBUILD_EXTMOD) +endif + # modpost option for external modules MODPOST += -e @@ -85,6 +97,14 @@ output-symdump := $(KBUILD_EXTMOD)/Module.symvers endif +# Get the SCM version of the module. Sed verifies setlocalversion returns +# a proper revision based on the SCM type, e.g. git, mercurial, or svn. +module_scmversion := $(shell $(srctree)/scripts/setlocalversion $(module_srcpath) | \ + sed -n 's/.*-\(\(g\|hg\)[a-fA-F0-9]\+\(-dirty\)\?\|svn[0-9]\+\).*/\1/p') +ifneq ($(module_scmversion),) +MODPOST += -v$(module_scmversion) +endif + # modpost options for modules (both in-kernel and external) MODPOST += \ $(addprefix -i ,$(wildcard $(input-symdump))) \ diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index f882ce0d9327..db71e0c9ab20 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -30,6 +30,8 @@ static int have_vmlinux = 0; static int all_versions = 0; /* If we are modposting external module set to 1 */ static int external_module = 0; +#define MODULE_SCMVERSION_SIZE 64 +static char module_scmversion[MODULE_SCMVERSION_SIZE]; /* Only warn about unresolved symbols */ static int warn_unresolved = 0; /* How a symbol is exported */ @@ -2272,6 +2274,20 @@ static void add_intree_flag(struct buffer *b, int is_intree) buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n"); } +/** + * add_scmversion() - Adds the MODULE_INFO macro for the scmversion. + * @b: Buffer to append to. + * + * This function fills in the module attribute `scmversion` for the kernel + * module. This is useful for determining a given module's SCM version on + * device via /sys/modules//scmversion and/or using the modinfo tool. + */ +static void add_scmversion(struct buffer *b) +{ + if (module_scmversion[0] != '\0') + buf_printf(b, "\nMODULE_INFO(scmversion, \"%s\");\n", module_scmversion); +} + /* Cannot check for assembler */ static void add_retpoline(struct buffer *b) { @@ -2559,7 +2575,7 @@ int main(int argc, char **argv) struct dump_list *dump_read_start = NULL; struct dump_list **dump_read_iter = &dump_read_start; - while ((opt = getopt(argc, argv, "ei:mnT:o:awENd:")) != -1) { + while ((opt = getopt(argc, argv, "ei:mnT:o:awENd:v:")) != -1) { switch (opt) { case 'e': external_module = 1; @@ -2597,6 +2613,11 @@ int main(int argc, char **argv) case 'd': missing_namespace_deps = optarg; break; + case 'v': + if (!optarg) + fatal("'-v' requires an argument defining the SCM version."); + strncpy(module_scmversion, optarg, sizeof(module_scmversion) - 1); + break; default: exit(1); } @@ -2645,6 +2666,7 @@ int main(int argc, char **argv) add_depends(&buf, mod); add_moddevtable(&buf, mod); add_srcversion(&buf, mod); + add_scmversion(&buf); sprintf(fname, "%s.mod.c", mod->name); write_if_changed(&buf, fname);