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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 03F2AC4345F for ; Mon, 22 Apr 2024 14:12:09 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 76FDA6B008A; Mon, 22 Apr 2024 10:12:08 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 71EC16B008C; Mon, 22 Apr 2024 10:12:08 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 599096B0093; Mon, 22 Apr 2024 10:12:08 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 3B8CB6B008A for ; Mon, 22 Apr 2024 10:12:08 -0400 (EDT) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id A6AE7120BCE for ; Mon, 22 Apr 2024 14:12:07 +0000 (UTC) X-FDA: 82037357094.18.3C90C13 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf06.hostedemail.com (Postfix) with ESMTP id D4749180018 for ; Mon, 22 Apr 2024 14:12:04 +0000 (UTC) Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=XZI2g4Uq; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf06.hostedemail.com: domain of mhiramat@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=mhiramat@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1713795125; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=zPZT0p2tlPyQpRUVayoTD5PAKmgTuHmAVvkl19jtRlU=; b=o/gd4NWEhQICv+LKdVDV4A6oA2USJo/yMoO/Ua2JHvEdEyjQvh7dmOaM4bqkfF+6nR86Zl toV2NYCWbfhC2xbTbknA3/JwgB+X2iw7jePbc8odMrDW4/GQmZncNS8s3HblqfMOE3I+MM mPY7+OIEYKiWNBnaHSBVcdIZ2v5RXYI= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=XZI2g4Uq; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf06.hostedemail.com: domain of mhiramat@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=mhiramat@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1713795125; a=rsa-sha256; cv=none; b=1F0SRzrq8GwWqlRXE+cMV6im4hLoqriGV6C8lHoRtDUqr95cLI07vVuvkoxMV9ldPGZ/36 2dkF0PgvTBx4NvwCsurXWmk2oAAY0HB1yVwo4DCUWHq+vvFmHaYb5hS5zv+BUdRVBtbirZ NI1OxrqxVIcHXAZ9DV2WYccrGMRlMqo= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id BA3F260DDE; Mon, 22 Apr 2024 14:12:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CAAD5C32783; Mon, 22 Apr 2024 14:11:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1713795123; bh=63rvt2yz8r57hl8myRcuStiGVHTSpmv479F+BVPlgOk=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=XZI2g4UqcleGPHMCMSqV3/iC7oJP0tZWbpfXP00rfR9bLCRfpzFMwC9X4q54oxXMM DnhZrHtKfWP5KsKR0UwBwIDd4eHpEkLzxxX7LPi42cCObWXCldmkT2ETPDxFRfwhiK nyXLCvvf3mWcIJjGAf2BRpg+sGk/r9FACse9FCIZKTAIMRKChgqXwhJ7CqFLLV8oy/ QLrmKiFkxPB4YBmwLg/Hf4QkKGO2SUvS8pCcc0bNoMWOtMRS3u0h3n+olJg1vGec5V 55mbL/zgu8a6qrqHPaT4tJ+d8LCTGjRW/TTRHz6/VaV0UanNJA0VfQalKnV9xzPuaQ EUKZMBGXl8nFQ== Date: Mon, 22 Apr 2024 23:11:51 +0900 From: Masami Hiramatsu (Google) To: Mike Rapoport Cc: linux-kernel@vger.kernel.org, Alexandre Ghiti , Andrew Morton , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Catalin Marinas , Christophe Leroy , "David S. Miller" , Dinh Nguyen , Donald Dutile , Eric Chanudet , Heiko Carstens , Helge Deller , Huacai Chen , Kent Overstreet , Luis Chamberlain , Mark Rutland , Masami Hiramatsu , Michael Ellerman , Nadav Amit , Palmer Dabbelt , Peter Zijlstra , Rick Edgecombe , Russell King , Sam Ravnborg , Song Liu , Steven Rostedt , Thomas Bogendoerfer , Thomas Gleixner , Will Deacon , bpf@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-modules@vger.kernel.org, linux-parisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, loongarch@lists.linux.dev, netdev@vger.kernel.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH v5 14/15] kprobes: remove dependency on CONFIG_MODULES Message-Id: <20240422231151.0d7c18ec1917887c7f323d4c@kernel.org> In-Reply-To: <20240422094436.3625171-15-rppt@kernel.org> References: <20240422094436.3625171-1-rppt@kernel.org> <20240422094436.3625171-15-rppt@kernel.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: D4749180018 X-Stat-Signature: o8hnhs9yywigeu8rdu6k6pchma3b1dwh X-HE-Tag: 1713795124-814758 X-HE-Meta: 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 NrPfbFgk EO70t9vdYppigFhyuEHMB2jNjO6+c5ovs/rfNr/mRWLD49bFPMOJA11im05yM78pej0cw4jOQjni6loHhZSC4pC3ki+QCIVSQFuvCkDQIggTgcxhybrajFeux+gYIyALZ62r59tRc9oIvusVkasEfwuI2bXIoBXNG2D0sRzvMZwM+uTAx/ZvbTGKzwFk6fxl/JnRKS9g+nBgW5EGdnliFcLFHiiJ9dm8k/+3AiBTK2jvT2BhoaSFWCsvo6bheUmUckoVBWQ0VNMFN6SynxBAjap7Ur8W5GJ0+mkjon1xHSkrt6NyOpYyhHFNftJer9UNrzElFiZrN7ba88mURI4wGiPN0KGlvnq7RSLCTx/tSmncPnvrrWhHxKgWroPVHNlGNEadHXE6jo/aAoTT1HBOOjhzjMDOR1QtxpIeCW5qxYMHIke30JroOBbwdzg== 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: List-Subscribe: List-Unsubscribe: On Mon, 22 Apr 2024 12:44:35 +0300 Mike Rapoport wrote: > From: "Mike Rapoport (IBM)" > > kprobes depended on CONFIG_MODULES because it has to allocate memory for > code. > > Since code allocations are now implemented with execmem, kprobes can be > enabled in non-modular kernels. > > Add #ifdef CONFIG_MODULE guards for the code dealing with kprobes inside > modules, make CONFIG_KPROBES select CONFIG_EXECMEM and drop the > dependency of CONFIG_KPROBES on CONFIG_MODULES. Looks good to me. Acked-by: Masami Hiramatsu (Google) Thank you! > > Signed-off-by: Mike Rapoport (IBM) > --- > arch/Kconfig | 2 +- > include/linux/module.h | 9 ++++++ > kernel/kprobes.c | 55 +++++++++++++++++++++++-------------- > kernel/trace/trace_kprobe.c | 20 +++++++++++++- > 4 files changed, 63 insertions(+), 23 deletions(-) > > diff --git a/arch/Kconfig b/arch/Kconfig > index 7006f71f0110..a48ce6a488b3 100644 > --- a/arch/Kconfig > +++ b/arch/Kconfig > @@ -52,9 +52,9 @@ config GENERIC_ENTRY > > config KPROBES > bool "Kprobes" > - depends on MODULES > depends on HAVE_KPROBES > select KALLSYMS > + select EXECMEM > select TASKS_RCU if PREEMPTION > help > Kprobes allows you to trap at almost any kernel address and > diff --git a/include/linux/module.h b/include/linux/module.h > index 1153b0d99a80..ffa1c603163c 100644 > --- a/include/linux/module.h > +++ b/include/linux/module.h > @@ -605,6 +605,11 @@ static inline bool module_is_live(struct module *mod) > return mod->state != MODULE_STATE_GOING; > } > > +static inline bool module_is_coming(struct module *mod) > +{ > + return mod->state == MODULE_STATE_COMING; > +} > + > struct module *__module_text_address(unsigned long addr); > struct module *__module_address(unsigned long addr); > bool is_module_address(unsigned long addr); > @@ -857,6 +862,10 @@ void *dereference_module_function_descriptor(struct module *mod, void *ptr) > return ptr; > } > > +static inline bool module_is_coming(struct module *mod) > +{ > + return false; > +} > #endif /* CONFIG_MODULES */ > > #ifdef CONFIG_SYSFS > diff --git a/kernel/kprobes.c b/kernel/kprobes.c > index ddd7cdc16edf..ca2c6cbd42d2 100644 > --- a/kernel/kprobes.c > +++ b/kernel/kprobes.c > @@ -1588,7 +1588,7 @@ static int check_kprobe_address_safe(struct kprobe *p, > } > > /* Get module refcount and reject __init functions for loaded modules. */ > - if (*probed_mod) { > + if (IS_ENABLED(CONFIG_MODULES) && *probed_mod) { > /* > * We must hold a refcount of the probed module while updating > * its code to prohibit unexpected unloading. > @@ -1603,12 +1603,13 @@ static int check_kprobe_address_safe(struct kprobe *p, > * kprobes in there. > */ > if (within_module_init((unsigned long)p->addr, *probed_mod) && > - (*probed_mod)->state != MODULE_STATE_COMING) { > + !module_is_coming(*probed_mod)) { > module_put(*probed_mod); > *probed_mod = NULL; > ret = -ENOENT; > } > } > + > out: > preempt_enable(); > jump_label_unlock(); > @@ -2488,24 +2489,6 @@ int kprobe_add_area_blacklist(unsigned long start, unsigned long end) > return 0; > } > > -/* Remove all symbols in given area from kprobe blacklist */ > -static void kprobe_remove_area_blacklist(unsigned long start, unsigned long end) > -{ > - struct kprobe_blacklist_entry *ent, *n; > - > - list_for_each_entry_safe(ent, n, &kprobe_blacklist, list) { > - if (ent->start_addr < start || ent->start_addr >= end) > - continue; > - list_del(&ent->list); > - kfree(ent); > - } > -} > - > -static void kprobe_remove_ksym_blacklist(unsigned long entry) > -{ > - kprobe_remove_area_blacklist(entry, entry + 1); > -} > - > int __weak arch_kprobe_get_kallsym(unsigned int *symnum, unsigned long *value, > char *type, char *sym) > { > @@ -2570,6 +2553,25 @@ static int __init populate_kprobe_blacklist(unsigned long *start, > return ret ? : arch_populate_kprobe_blacklist(); > } > > +#ifdef CONFIG_MODULES > +/* Remove all symbols in given area from kprobe blacklist */ > +static void kprobe_remove_area_blacklist(unsigned long start, unsigned long end) > +{ > + struct kprobe_blacklist_entry *ent, *n; > + > + list_for_each_entry_safe(ent, n, &kprobe_blacklist, list) { > + if (ent->start_addr < start || ent->start_addr >= end) > + continue; > + list_del(&ent->list); > + kfree(ent); > + } > +} > + > +static void kprobe_remove_ksym_blacklist(unsigned long entry) > +{ > + kprobe_remove_area_blacklist(entry, entry + 1); > +} > + > static void add_module_kprobe_blacklist(struct module *mod) > { > unsigned long start, end; > @@ -2672,6 +2674,17 @@ static struct notifier_block kprobe_module_nb = { > .priority = 0 > }; > > +static int kprobe_register_module_notifier(void) > +{ > + return register_module_notifier(&kprobe_module_nb); > +} > +#else > +static int kprobe_register_module_notifier(void) > +{ > + return 0; > +} > +#endif /* CONFIG_MODULES */ > + > void kprobe_free_init_mem(void) > { > void *start = (void *)(&__init_begin); > @@ -2731,7 +2744,7 @@ static int __init init_kprobes(void) > if (!err) > err = register_die_notifier(&kprobe_exceptions_nb); > if (!err) > - err = register_module_notifier(&kprobe_module_nb); > + err = kprobe_register_module_notifier(); > > kprobes_initialized = (err == 0); > kprobe_sysctls_init(); > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > index 14099cc17fc9..2cb2a3951b4f 100644 > --- a/kernel/trace/trace_kprobe.c > +++ b/kernel/trace/trace_kprobe.c > @@ -111,6 +111,7 @@ static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk, > return strncmp(module_name(mod), name, len) == 0 && name[len] == ':'; > } > > +#ifdef CONFIG_MODULES > static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) > { > char *p; > @@ -129,6 +130,12 @@ static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) > > return ret; > } > +#else > +static inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) > +{ > + return false; > +} > +#endif > > static bool trace_kprobe_is_busy(struct dyn_event *ev) > { > @@ -670,6 +677,7 @@ static int register_trace_kprobe(struct trace_kprobe *tk) > return ret; > } > > +#ifdef CONFIG_MODULES > /* Module notifier call back, checking event on the module */ > static int trace_kprobe_module_callback(struct notifier_block *nb, > unsigned long val, void *data) > @@ -704,6 +712,16 @@ static struct notifier_block trace_kprobe_module_nb = { > .notifier_call = trace_kprobe_module_callback, > .priority = 1 /* Invoked after kprobe module callback */ > }; > +static int trace_kprobe_register_module_notifier(void) > +{ > + return register_module_notifier(&trace_kprobe_module_nb); > +} > +#else > +static int trace_kprobe_register_module_notifier(void) > +{ > + return 0; > +} > +#endif /* CONFIG_MODULES */ > > static int count_symbols(void *data, unsigned long unused) > { > @@ -1933,7 +1951,7 @@ static __init int init_kprobe_trace_early(void) > if (ret) > return ret; > > - if (register_module_notifier(&trace_kprobe_module_nb)) > + if (trace_kprobe_register_module_notifier()) > return -EINVAL; > > return 0; > -- > 2.43.0 > -- Masami Hiramatsu (Google)