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=-10.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 BD925C433E1 for ; Fri, 24 Jul 2020 14:46:39 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7E7CA2065F for ; Fri, 24 Jul 2020 14:46:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="ia0fI2bU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7E7CA2065F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 12D748D0016; Fri, 24 Jul 2020 10:46:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 105B78D0001; Fri, 24 Jul 2020 10:46:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 041F98D0016; Fri, 24 Jul 2020 10:46:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0219.hostedemail.com [216.40.44.219]) by kanga.kvack.org (Postfix) with ESMTP id E20228D0001 for ; Fri, 24 Jul 2020 10:46:38 -0400 (EDT) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 803A98131 for ; Fri, 24 Jul 2020 14:46:38 +0000 (UTC) X-FDA: 77073245676.01.can40_4f0cac426f48 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin01.hostedemail.com (Postfix) with ESMTP id 4AC281005AC13 for ; Fri, 24 Jul 2020 14:46:38 +0000 (UTC) X-HE-Tag: can40_4f0cac426f48 X-Filterd-Recvd-Size: 5063 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf24.hostedemail.com (Postfix) with ESMTP for ; Fri, 24 Jul 2020 14:46:37 +0000 (UTC) Received: from devnote2 (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1C9BD2065E; Fri, 24 Jul 2020 14:46:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595601996; bh=xAHnG2Hy+DQIFym5s+rANLi7W4SNe3rVMEhADkf1cgg=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=ia0fI2bU+Tpmd81+fVmhsa+CaE2enWOGw6tvkEcB1EdcmscoL0F+Ge0qAiM6z7wdF jQ5d02eSQ2lIlAi8gQono/ETw36XJWmdtEnOE7iaJIKsPTDNGj14KBbgrhUxr7WwV7 EWa3ZNAk6q+KznVKGQoXMimXaugXxjt0KaWmGTgo= Date: Fri, 24 Jul 2020 23:46:31 +0900 From: Masami Hiramatsu To: Jarkko Sakkinen Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andi Kleen , Peter Zijlstra , Masami Hiramatsu , Jessica Yu , "Naveen N. Rao" , Anil S Keshavamurthy , "David S. Miller" , Steven Rostedt , Ingo Molnar Subject: Re: [PATCH v5 1/6] kprobes: Remove dependency to the module_mutex Message-Id: <20200724234631.40f4ffec6adae57ac3df8ea3@kernel.org> In-Reply-To: <20200724050553.1724168-2-jarkko.sakkinen@linux.intel.com> References: <20200724050553.1724168-1-jarkko.sakkinen@linux.intel.com> <20200724050553.1724168-2-jarkko.sakkinen@linux.intel.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4AC281005AC13 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam01 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, 24 Jul 2020 08:05:48 +0300 Jarkko Sakkinen wrote: > Add lock_modules() and unlock_modules() wrappers for acquiring module_mutex > in order to remove the compile time dependency to it. This subject is a bit confusing. This is just wrapping modules_mutex in kpprobes. We still have compile time dependency, e.g. module_state, right? Thank you, > > Cc: linux-mm@kvack.org > Cc: Andi Kleen > Cc: Peter Zijlstra > Suggested-by: Masami Hiramatsu > Signed-off-by: Jarkko Sakkinen > --- > include/linux/module.h | 18 ++++++++++++++++++ > kernel/kprobes.c | 4 ++-- > kernel/trace/trace_kprobe.c | 4 ++-- > 3 files changed, 22 insertions(+), 4 deletions(-) > > diff --git a/include/linux/module.h b/include/linux/module.h > index 2e6670860d27..8850b9692b8f 100644 > --- a/include/linux/module.h > +++ b/include/linux/module.h > @@ -705,6 +705,16 @@ static inline bool is_livepatch_module(struct module *mod) > bool is_module_sig_enforced(void); > void set_module_sig_enforced(void); > > +static inline void lock_modules(void) > +{ > + mutex_lock(&module_mutex); > +} > + > +static inline void unlock_modules(void) > +{ > + mutex_unlock(&module_mutex); > +} > + > #else /* !CONFIG_MODULES... */ > > static inline struct module *__module_address(unsigned long addr) > @@ -852,6 +862,14 @@ void *dereference_module_function_descriptor(struct module *mod, void *ptr) > return ptr; > } > > +static inline void lock_modules(void) > +{ > +} > + > +static inline void unlock_modules(void) > +{ > +} > + > #endif /* CONFIG_MODULES */ > > #ifdef CONFIG_SYSFS > diff --git a/kernel/kprobes.c b/kernel/kprobes.c > index 2e97febeef77..4e46d96d4e16 100644 > --- a/kernel/kprobes.c > +++ b/kernel/kprobes.c > @@ -564,7 +564,7 @@ static void kprobe_optimizer(struct work_struct *work) > cpus_read_lock(); > mutex_lock(&text_mutex); > /* Lock modules while optimizing kprobes */ > - mutex_lock(&module_mutex); > + lock_modules(); > > /* > * Step 1: Unoptimize kprobes and collect cleaned (unused and disarmed) > @@ -589,7 +589,7 @@ static void kprobe_optimizer(struct work_struct *work) > /* Step 4: Free cleaned kprobes after quiesence period */ > do_free_cleaned_kprobes(); > > - mutex_unlock(&module_mutex); > + unlock_modules(); > mutex_unlock(&text_mutex); > cpus_read_unlock(); > > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > index aefb6065b508..710ec6a6aa8f 100644 > --- a/kernel/trace/trace_kprobe.c > +++ b/kernel/trace/trace_kprobe.c > @@ -122,9 +122,9 @@ static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) > if (!p) > return true; > *p = '\0'; > - mutex_lock(&module_mutex); > + lock_modules(); > ret = !!find_module(tk->symbol); > - mutex_unlock(&module_mutex); > + unlock_modules(); > *p = ':'; > > return ret; > -- > 2.25.1 > -- Masami Hiramatsu