From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 21A7DC43387 for ; Sun, 16 Dec 2018 13:11:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E4E1F2086C for ; Sun, 16 Dec 2018 13:11:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730444AbeLPNLz (ORCPT ); Sun, 16 Dec 2018 08:11:55 -0500 Received: from www.osadl.org ([62.245.132.105]:47366 "EHLO www.osadl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730197AbeLPNLy (ORCPT ); Sun, 16 Dec 2018 08:11:54 -0500 Received: from debian01.hofrr.at (178.115.242.59.static.drei.at [178.115.242.59]) by www.osadl.org (8.13.8/8.13.8/OSADL-2007092901) with ESMTP id wBGDBNQU021573; Sun, 16 Dec 2018 14:11:23 +0100 From: Nicholas Mc Guire To: Josh Poimboeuf Cc: Jessica Yu , Jiri Kosina , Miroslav Benes , Petr Mladek , live-patching@vger.kernel.org, linux-kernel@vger.kernel.org, Nicholas Mc Guire Subject: [PATCH V2] livepatch: fix non-static warnings Date: Sun, 16 Dec 2018 14:07:37 +0100 Message-Id: <1544965657-26804-1-git-send-email-hofrat@osadl.org> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sparse reported warnings about non-static symbols. For the variables a simple static attribute is fine - for those symbols referenced by livepatch via klp_func the symbol-names must be unmodified in the symbol table - to resolve this the __noclone attribute is used for the shared statically declared functions. Signed-off-by: Nicholas Mc Guire Suggested-by: Joe Lawrence Link: https://lkml.org/lkml/2018/12/13/827 --- V2: not all static functions shared need to carry the __noclone attribute only those that need to be resolved at runtime by livepatch - so drop the unnecessary __noclone attributes as well as the Note on __noclone as suggested by Joe Lawrence - thanks ! Sparse reported the following findings: CHECK samples/livepatch/livepatch-shadow-mod.c samples/livepatch/livepatch-shadow-mod.c:99:1: warning: symbol 'dummy_list' was not declared. Should it be static? samples/livepatch/livepatch-shadow-mod.c:100:1: warning: symbol 'dummy_list_mutex' was not declared. Should it be static? samples/livepatch/livepatch-shadow-mod.c:107:23: warning: symbol 'dummy_alloc' was not declared. Should it be static? samples/livepatch/livepatch-shadow-mod.c:128:15: warning: symbol 'dummy_free' was not declared. Should it be static? samples/livepatch/livepatch-shadow-mod.c:136:15: warning: symbol 'dummy_check' was not declared. Should it be static? CHECK samples/livepatch/livepatch-shadow-fix1.c samples/livepatch/livepatch-shadow-fix1.c:74:14: warning: symbol 'livepatch_fix1_dummy_alloc' was not declared. Should it be static? samples/livepatch/livepatch-shadow-fix1.c:111:6: warning: symbol 'livepatch_fix1_dummy_free' was not declared. Should it be static? CHECK samples/livepatch/livepatch-shadow-fix2.c samples/livepatch/livepatch-shadow-fix2.c:53:6: warning: symbol 'livepatch_fix2_dummy_check' was not declared. Should it be static? samples/livepatch/livepatch-shadow-fix2.c:81:6: warning: symbol 'livepatch_fix2_dummy_free' was not declared. Should it be static? Patch was compile tested with: x86_64_defconfig + FTRACE=y FUNCTION_TRACER=y, EXPERT=y, LATENCYTOP=y, SAMPLES=y, SAMPLE_LIVEPATCH=y Patch was runtested with: insmod samples/livepatch/livepatch-shadow-mod.ko insmod samples/livepatch/livepatch-shadow-fix1.ko insmod samples/livepatch/livepatch-shadow-fix2.ko echo 0 > /sys/kernel/livepatch/livepatch_shadow_fix2/enabled echo 0 > /sys/kernel/livepatch/livepatch_shadow_fix1/enabled rmmod livepatch-shadow-fix2 rmmod livepatch-shadow-fix1 rmmod livepatch-shadow-mod and dmesg output compared with the run before the patch was applied. Patch is against 4.20-rc6 (localversion-next is next-20181214) samples/livepatch/livepatch-shadow-fix1.c | 4 ++-- samples/livepatch/livepatch-shadow-fix2.c | 4 ++-- samples/livepatch/livepatch-shadow-mod.c | 11 ++++++----- 3 files changed, 10 insertions(+), 9 deletions(-) diff --git a/samples/livepatch/livepatch-shadow-fix1.c b/samples/livepatch/livepatch-shadow-fix1.c index 49b1355..ebe78e2 100644 --- a/samples/livepatch/livepatch-shadow-fix1.c +++ b/samples/livepatch/livepatch-shadow-fix1.c @@ -71,7 +71,7 @@ static int shadow_leak_ctor(void *obj, void *shadow_data, void *ctor_data) return 0; } -struct dummy *livepatch_fix1_dummy_alloc(void) +static struct dummy *livepatch_fix1_dummy_alloc(void) { struct dummy *d; void *leak; @@ -108,7 +108,7 @@ static void livepatch_fix1_dummy_leak_dtor(void *obj, void *shadow_data) __func__, d, *shadow_leak); } -void livepatch_fix1_dummy_free(struct dummy *d) +static void livepatch_fix1_dummy_free(struct dummy *d) { void **shadow_leak; diff --git a/samples/livepatch/livepatch-shadow-fix2.c b/samples/livepatch/livepatch-shadow-fix2.c index b34c7bf..b6dac2b 100644 --- a/samples/livepatch/livepatch-shadow-fix2.c +++ b/samples/livepatch/livepatch-shadow-fix2.c @@ -50,7 +50,7 @@ struct dummy { unsigned long jiffies_expire; }; -bool livepatch_fix2_dummy_check(struct dummy *d, unsigned long jiffies) +static bool livepatch_fix2_dummy_check(struct dummy *d, unsigned long jiffies) { int *shadow_count; @@ -78,7 +78,7 @@ static void livepatch_fix2_dummy_leak_dtor(void *obj, void *shadow_data) __func__, d, *shadow_leak); } -void livepatch_fix2_dummy_free(struct dummy *d) +static void livepatch_fix2_dummy_free(struct dummy *d) { void **shadow_leak; int *shadow_count; diff --git a/samples/livepatch/livepatch-shadow-mod.c b/samples/livepatch/livepatch-shadow-mod.c index 4c54b25..2168d57 100644 --- a/samples/livepatch/livepatch-shadow-mod.c +++ b/samples/livepatch/livepatch-shadow-mod.c @@ -96,15 +96,15 @@ MODULE_DESCRIPTION("Buggy module for shadow variable demo"); * Keep a list of all the dummies so we can clean up any residual ones * on module exit */ -LIST_HEAD(dummy_list); -DEFINE_MUTEX(dummy_list_mutex); +static LIST_HEAD(dummy_list); +static DEFINE_MUTEX(dummy_list_mutex); struct dummy { struct list_head list; unsigned long jiffies_expire; }; -noinline struct dummy *dummy_alloc(void) +static __noclone noinline struct dummy *dummy_alloc(void) { struct dummy *d; void *leak; @@ -125,7 +125,7 @@ noinline struct dummy *dummy_alloc(void) return d; } -noinline void dummy_free(struct dummy *d) +static __noclone noinline void dummy_free(struct dummy *d) { pr_info("%s: dummy @ %p, expired = %lx\n", __func__, d, d->jiffies_expire); @@ -133,7 +133,8 @@ noinline void dummy_free(struct dummy *d) kfree(d); } -noinline bool dummy_check(struct dummy *d, unsigned long jiffies) +static __noclone noinline bool dummy_check(struct dummy *d, + unsigned long jiffies) { return time_after(jiffies, d->jiffies_expire); } -- 2.1.4