From patchwork Mon May 6 01:34:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 10930453 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D0FFD92A for ; Mon, 6 May 2019 01:35:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B770627F91 for ; Mon, 6 May 2019 01:35:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8F39B2864B; Mon, 6 May 2019 01:35:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6E23A27F91 for ; Mon, 6 May 2019 01:35:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725846AbfEFBfI (ORCPT ); Sun, 5 May 2019 21:35:08 -0400 Received: from mail-pg1-f195.google.com ([209.85.215.195]:40689 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725786AbfEFBfI (ORCPT ); Sun, 5 May 2019 21:35:08 -0400 Received: by mail-pg1-f195.google.com with SMTP id d31so5637798pgl.7 for ; Sun, 05 May 2019 18:35:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=1bZS6QNu3Og8dmYIBYZs/QPsWGTr16uK5TDgJ7mlBd8=; b=oFoSAFGkkSQZQTESShUDzd5h4YLrcvOJdgh2qNjtweZWVbz4UktLQhSdeAspAMd9U/ 9NJgdIdcsPyU/TTbjbkYnrhMgXTxjumbAEVOlaUk9ApBJvgVUtSIB3BOrRpc9Ku/Z4Zz zpRlsjxL8HyX0+HAb4Qa9MLSm7jH8m2SJUKE4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=1bZS6QNu3Og8dmYIBYZs/QPsWGTr16uK5TDgJ7mlBd8=; b=ZnnAl1lqAdXxMuCSa5unEgeSNqoMW/hH2dX13QEa9kyBu8Z/pQ/a26M3VJcskH2Uu6 K7wugxkjTr6T4AAWyTUtTMEflQB5ZdRwRdK1Tzx8cor0eBVZsbaBnylkw+VCAnMnB7EX zGUhzxq5Zet6FFRqSLep29dkeTSAwXxPejRYPe4goj9NC3aIqRA0sxKJTZuWlmYU6+TN R0ONXxJJ41fX77Rfp8jgChXCGXt0Yio4nsdyJp4LE3PV3s/1W4cd9ycN6pLdQ206AS0t k3be1636sAEX/xvIahaFYYvlS+qusNChfJxaZ9QiVYsLHqypZlZVrdgUYpoutPs8Bx4T 6wFw== X-Gm-Message-State: APjAAAX9jm45JhKSyhEYmBFQbbOwOWIYjAftRW+qC1zkniofUZRalXVA 9MPB52oCDlDC2CDURbphgvB+bA== X-Google-Smtp-Source: APXvYqyMqjH1rv8o1a5MG6lttWXnrtTTnVkW2pdmDmafQmbF4Z2cWekbCd1pLswsBkrlxyLONtca4g== X-Received: by 2002:a62:46c7:: with SMTP id o68mr30726847pfi.54.1557106507313; Sun, 05 May 2019 18:35:07 -0700 (PDT) Received: from joelaf.cam.corp.google.com ([2620:15c:6:12:9c46:e0da:efbf:69cc]) by smtp.gmail.com with ESMTPSA id m131sm15649677pga.3.2019.05.05.18.35.01 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Sun, 05 May 2019 18:35:05 -0700 (PDT) From: "Joel Fernandes (Google)" To: linux-kernel@vger.kernel.org Cc: "Joel Fernandes (Google)" , Steven Rostedt , Adrian Ratiu , Alexei Starovoitov , Andrew Morton , atishp04@gmail.com, bpf@vger.kernel.org, Brendan Gregg , Brendan Gregg , dancol@google.com, Daniel Borkmann , Dan Williams , dietmar.eggemann@arm.com, duyuchao , gregkh@linuxfoundation.org, Guenter Roeck , Jonathan Corbet , Karim Yaghmour , Kees Cook , kernel-team@android.com, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-trace-devel@vger.kernel.org, Manjo Raja Rao , Masahiro Yamada , Masami Hiramatsu , =?utf-8?q?Micha=C5=82_Gregorczyk?= , Michal Gregorczyk , Mohammad Husain , Olof Johansson , qais.yousef@arm.com, rdunlap@infradead.org, Shuah Khan , Srinivas Ramana , Tamir Carmeli , yhs@fb.com Subject: [PATCH v3] kheaders: Move from proc to sysfs Date: Sun, 5 May 2019 21:34:56 -0400 Message-Id: <20190506013456.86061-1-joel@joelfernandes.org> X-Mailer: git-send-email 2.21.0.1020.gf2820cf01a-goog MIME-Version: 1.0 Sender: linux-trace-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The kheaders archive consisting of the kernel headers used for compiling bpf programs is in /proc. However there is concern that moving it here will make it permanent. Let us move it to /sys/kernel as discussed [1]. [1] https://lore.kernel.org/patchwork/patch/1067310/#1265969 Suggested-by: Steven Rostedt Signed-off-by: Joel Fernandes (Google) --- This patch applies on top of the previous patch that was applied to the driver tree: https://lore.kernel.org/patchwork/patch/1067310/ v2->v3: Fixed sysfs file mode nit (Greg). v1->v2: Fixed some kconfig nits. init/Kconfig | 16 ++++----- kernel/Makefile | 4 +-- kernel/{gen_ikh_data.sh => gen_kheaders.sh} | 2 +- kernel/kheaders.c | 40 +++++++++------------ 4 files changed, 26 insertions(+), 36 deletions(-) rename kernel/{gen_ikh_data.sh => gen_kheaders.sh} (98%) diff --git a/init/Kconfig b/init/Kconfig index 26a364a95b57..c3661991b089 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -579,15 +579,13 @@ config IKCONFIG_PROC This option enables access to the kernel configuration file through /proc/config.gz. -config IKHEADERS_PROC - tristate "Enable kernel header artifacts through /proc/kheaders.tar.xz" - depends on PROC_FS - help - This option enables access to the kernel header and other artifacts that - are generated during the build process. These can be used to build eBPF - tracing programs, or similar programs. If you build the headers as a - module, a module called kheaders.ko is built which can be loaded on-demand - to get access to the headers. +config IKHEADERS + tristate "Enable kernel headers through /sys/kernel/kheaders.tar.xz" + help + This option enables access to the in-kernel headers that are generated during + the build process. These can be used to build eBPF tracing programs, + or similar programs. If you build the headers as a module, a module called + kheaders.ko is built which can be loaded on-demand to get access to headers. config LOG_BUF_SHIFT int "Kernel log buffer size (16 => 64KB, 17 => 128KB)" diff --git a/kernel/Makefile b/kernel/Makefile index 12399614c350..b32a558fae2f 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -70,7 +70,7 @@ obj-$(CONFIG_UTS_NS) += utsname.o obj-$(CONFIG_USER_NS) += user_namespace.o obj-$(CONFIG_PID_NS) += pid_namespace.o obj-$(CONFIG_IKCONFIG) += configs.o -obj-$(CONFIG_IKHEADERS_PROC) += kheaders.o +obj-$(CONFIG_IKHEADERS) += kheaders.o obj-$(CONFIG_SMP) += stop_machine.o obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o obj-$(CONFIG_AUDIT) += audit.o auditfilter.o @@ -126,7 +126,7 @@ $(obj)/config_data.gz: $(KCONFIG_CONFIG) FORCE $(obj)/kheaders.o: $(obj)/kheaders_data.tar.xz quiet_cmd_genikh = CHK $(obj)/kheaders_data.tar.xz -cmd_genikh = $(srctree)/kernel/gen_ikh_data.sh $@ +cmd_genikh = $(srctree)/kernel/gen_kheaders.sh $@ $(obj)/kheaders_data.tar.xz: FORCE $(call cmd,genikh) diff --git a/kernel/gen_ikh_data.sh b/kernel/gen_kheaders.sh similarity index 98% rename from kernel/gen_ikh_data.sh rename to kernel/gen_kheaders.sh index 591a94f7b387..581b83534587 100755 --- a/kernel/gen_ikh_data.sh +++ b/kernel/gen_kheaders.sh @@ -2,7 +2,7 @@ # SPDX-License-Identifier: GPL-2.0 # This script generates an archive consisting of kernel headers -# for CONFIG_IKHEADERS_PROC. +# for CONFIG_IKHEADERS. set -e spath="$(dirname "$(readlink -f "$0")")" kroot="$spath/.." diff --git a/kernel/kheaders.c b/kernel/kheaders.c index 70ae6052920d..8f69772af77b 100644 --- a/kernel/kheaders.c +++ b/kernel/kheaders.c @@ -8,9 +8,8 @@ #include #include -#include +#include #include -#include /* * Define kernel_headers_data and kernel_headers_data_end, within which the @@ -31,39 +30,32 @@ extern char kernel_headers_data; extern char kernel_headers_data_end; static ssize_t -ikheaders_read_current(struct file *file, char __user *buf, - size_t len, loff_t *offset) +ikheaders_read(struct file *file, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t len) { - return simple_read_from_buffer(buf, len, offset, - &kernel_headers_data, - &kernel_headers_data_end - - &kernel_headers_data); + memcpy(buf, &kernel_headers_data + off, len); + return len; } -static const struct file_operations ikheaders_file_ops = { - .read = ikheaders_read_current, - .llseek = default_llseek, +static struct bin_attribute kheaders_attr __ro_after_init = { + .attr = { + .name = "kheaders.tar.xz", + .mode = 0444, + }, + .read = &ikheaders_read, }; static int __init ikheaders_init(void) { - struct proc_dir_entry *entry; - - /* create the current headers file */ - entry = proc_create("kheaders.tar.xz", S_IRUGO, NULL, - &ikheaders_file_ops); - if (!entry) - return -ENOMEM; - - proc_set_size(entry, - &kernel_headers_data_end - - &kernel_headers_data); - return 0; + kheaders_attr.size = (&kernel_headers_data_end - + &kernel_headers_data); + return sysfs_create_bin_file(kernel_kobj, &kheaders_attr); } static void __exit ikheaders_cleanup(void) { - remove_proc_entry("kheaders.tar.xz", NULL); + sysfs_remove_bin_file(kernel_kobj, &kheaders_attr); } module_init(ikheaders_init);