Linux-arch Archive mirror
 help / color / mirror / Atom feed
From: Masami Hiramatsu <masami.hiramatsu@gmail.com>
To: Mike Rapoport <rppt@kernel.org>
Cc: linux-kernel@vger.kernel.org,
	"Alexandre Ghiti" <alexghiti@rivosinc.com>,
	"Andrew Morton" <akpm@linux-foundation.org>,
	"Björn Töpel" <bjorn@kernel.org>,
	"Catalin Marinas" <catalin.marinas@arm.com>,
	"Christophe Leroy" <christophe.leroy@csgroup.eu>,
	"David S. Miller" <davem@davemloft.net>,
	"Dinh Nguyen" <dinguyen@kernel.org>,
	"Donald Dutile" <ddutile@redhat.com>,
	"Eric Chanudet" <echanude@redhat.com>,
	"Heiko Carstens" <hca@linux.ibm.com>,
	"Helge Deller" <deller@gmx.de>,
	"Huacai Chen" <chenhuacai@kernel.org>,
	"Kent Overstreet" <kent.overstreet@linux.dev>,
	"Luis Chamberlain" <mcgrof@kernel.org>,
	"Mark Rutland" <mark.rutland@arm.com>,
	"Michael Ellerman" <mpe@ellerman.id.au>,
	"Nadav Amit" <nadav.amit@gmail.com>,
	"Palmer Dabbelt" <palmer@dabbelt.com>,
	"Puranjay Mohan" <puranjay12@gmail.com>,
	"Rick Edgecombe" <rick.p.edgecombe@intel.com>,
	"Russell King" <linux@armlinux.org.uk>,
	"Song Liu" <song@kernel.org>,
	"Steven Rostedt" <rostedt@goodmis.org>,
	"Thomas Bogendoerfer" <tsbogend@alpha.franken.de>,
	"Thomas Gleixner" <tglx@linutronix.de>,
	"Will Deacon" <will@kernel.org>,
	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 v4 14/15] kprobes: remove dependency on CONFIG_MODULES
Date: Thu, 18 Apr 2024 06:16:15 +0900	[thread overview]
Message-ID: <20240418061615.5fad23b954bf317c029acc4d@gmail.com> (raw)
In-Reply-To: <20240411160051.2093261-15-rppt@kernel.org>

Hi Mike,

On Thu, 11 Apr 2024 19:00:50 +0300
Mike Rapoport <rppt@kernel.org> wrote:

> From: "Mike Rapoport (IBM)" <rppt@kernel.org>
> 
> 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.

Thanks for this work, but this conflicts with the latest fix in v6.9-rc4.
Also, can you use IS_ENABLED(CONFIG_MODULES) instead of #ifdefs in
function body? We have enough dummy functions for that, so it should
not make a problem.

Thank you,

> 
> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
> ---
>  arch/Kconfig                |  2 +-
>  kernel/kprobes.c            | 43 +++++++++++++++++++++----------------
>  kernel/trace/trace_kprobe.c | 11 ++++++++++
>  3 files changed, 37 insertions(+), 19 deletions(-)
> 
> diff --git a/arch/Kconfig b/arch/Kconfig
> index bc9e8e5dccd5..68177adf61a0 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/kernel/kprobes.c b/kernel/kprobes.c
> index 047ca629ce49..90c056853e6f 100644
> --- a/kernel/kprobes.c
> +++ b/kernel/kprobes.c
> @@ -1580,6 +1580,7 @@ static int check_kprobe_address_safe(struct kprobe *p,
>  		goto out;
>  	}
>  
> +#ifdef CONFIG_MODULES
>  	/* Check if 'p' is probing a module. */
>  	*probed_mod = __module_text_address((unsigned long) p->addr);
>  	if (*probed_mod) {
> @@ -1603,6 +1604,8 @@ static int check_kprobe_address_safe(struct kprobe *p,
>  			ret = -ENOENT;
>  		}
>  	}
> +#endif
> +
>  out:
>  	preempt_enable();
>  	jump_label_unlock();
> @@ -2482,24 +2485,6 @@ 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)
>  {
> @@ -2564,6 +2549,25 @@ 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;
> @@ -2665,6 +2669,7 @@ static struct notifier_block kprobe_module_nb = {
>  	.notifier_call = kprobes_module_callback,
>  	.priority = 0
>  };
> +#endif
>  
>  void kprobe_free_init_mem(void)
>  {
> @@ -2724,8 +2729,10 @@ static int __init init_kprobes(void)
>  	err = arch_init_kprobes();
>  	if (!err)
>  		err = register_die_notifier(&kprobe_exceptions_nb);
> +#ifdef CONFIG_MODULES
>  	if (!err)
>  		err = register_module_notifier(&kprobe_module_nb);
> +#endif
>  
>  	kprobes_initialized = (err == 0);
>  	kprobe_sysctls_init();
> diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
> index 14099cc17fc9..f0610137d6a3 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 +712,7 @@ static struct notifier_block trace_kprobe_module_nb = {
>  	.notifier_call = trace_kprobe_module_callback,
>  	.priority = 1	/* Invoked after kprobe module callback */
>  };
> +#endif
>  
>  static int count_symbols(void *data, unsigned long unused)
>  {
> @@ -1933,8 +1942,10 @@ static __init int init_kprobe_trace_early(void)
>  	if (ret)
>  		return ret;
>  
> +#ifdef CONFIG_MODULES
>  	if (register_module_notifier(&trace_kprobe_module_nb))
>  		return -EINVAL;
> +#endif
>  
>  	return 0;
>  }
> -- 
> 2.43.0
> 
> 


-- 
Masami Hiramatsu

  reply	other threads:[~2024-04-17 21:16 UTC|newest]

Thread overview: 52+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-04-11 16:00 [PATCH v4 00/15] mm: jit/text allocator Mike Rapoport
2024-04-11 16:00 ` [PATCH v4 01/15] arm64: module: remove uneeded call to kasan_alloc_module_shadow() Mike Rapoport
2024-04-11 16:00 ` [PATCH v4 02/15] mips: module: rename MODULE_START to MODULES_VADDR Mike Rapoport
2024-04-11 16:00 ` [PATCH v4 03/15] nios2: define virtual address space for modules Mike Rapoport
2024-04-11 16:00 ` [PATCH v4 04/15] module: make module_memory_{alloc,free} more self-contained Mike Rapoport
2024-04-11 16:00 ` [PATCH v4 05/15] mm: introduce execmem_alloc() and execmem_free() Mike Rapoport
2024-04-11 19:42   ` Luis Chamberlain
2024-04-14  6:53     ` Mike Rapoport
2024-04-12  9:16   ` Ingo Molnar
2024-04-14  6:54     ` Mike Rapoport
2024-04-15  7:52   ` Peter Zijlstra
2024-04-15 16:51     ` Mike Rapoport
2024-04-15 17:36     ` Mark Rutland
2024-04-16  7:22       ` Mike Rapoport
2024-04-17 23:32         ` Song Liu
2024-04-18 15:35           ` Mike Rapoport
2024-04-18 16:13             ` Song Liu
2024-04-18 17:52               ` Mike Rapoport
2024-04-18 21:01                 ` Song Liu
2024-04-19  6:55                   ` Mike Rapoport
2024-04-19 15:54                     ` Song Liu
2024-04-19 17:02                       ` Mike Rapoport
2024-04-19 17:32                         ` Song Liu
2024-04-19 19:59                           ` Mike Rapoport
2024-04-19 21:42                             ` Song Liu
2024-04-20  4:22                               ` Mike Rapoport
2024-04-20  9:11                                 ` Masami Hiramatsu
2024-04-22 18:32                                   ` Song Liu
2024-04-17 21:06   ` Masami Hiramatsu
2024-04-11 16:00 ` [PATCH v4 06/15] mm/execmem, arch: convert simple overrides of module_alloc to execmem Mike Rapoport
2024-04-11 20:53   ` Sam Ravnborg
2024-04-14  7:26     ` Mike Rapoport
2024-04-15  8:03   ` Peter Zijlstra
2024-04-11 16:00 ` [PATCH v4 07/15] mm/execmem, arch: convert remaining " Mike Rapoport
2024-04-15  9:36   ` Peter Zijlstra
2024-04-11 16:00 ` [PATCH v4 08/15] arm64: extend execmem_info for generated code allocations Mike Rapoport
2024-04-11 16:00 ` [PATCH v4 09/15] riscv: extend execmem_params " Mike Rapoport
2024-04-11 16:00 ` [PATCH v4 10/15] powerpc: extend execmem_params for kprobes allocations Mike Rapoport
2024-04-11 16:00 ` [PATCH v4 11/15] arch: make execmem setup available regardless of CONFIG_MODULES Mike Rapoport
2024-04-11 16:00 ` [PATCH v4 12/15] x86/ftrace: enable dynamic ftrace without CONFIG_MODULES Mike Rapoport
2024-04-11 16:00 ` [PATCH v4 13/15] powerpc: use CONFIG_EXECMEM instead of CONFIG_MODULES where appropiate Mike Rapoport
2024-04-11 16:00 ` [PATCH v4 14/15] kprobes: remove dependency on CONFIG_MODULES Mike Rapoport
2024-04-17 21:16   ` Masami Hiramatsu [this message]
2024-04-18 15:37     ` Mike Rapoport
2024-04-19 15:49     ` Mike Rapoport
2024-04-19 15:59       ` Christophe Leroy
2024-04-20  7:33         ` Mike Rapoport
2024-04-20  9:15           ` Masami Hiramatsu
2024-04-20 10:52             ` Mike Rapoport
2024-04-11 16:00 ` [PATCH v4 15/15] bpf: remove CONFIG_BPF_JIT dependency on CONFIG_MODULES of Mike Rapoport
2024-04-11 18:00 ` [PATCH v4 00/15] mm: jit/text allocator Kent Overstreet
2024-04-11 19:45 ` Luis Chamberlain

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20240418061615.5fad23b954bf317c029acc4d@gmail.com \
    --to=masami.hiramatsu@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=alexghiti@rivosinc.com \
    --cc=bjorn@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=catalin.marinas@arm.com \
    --cc=chenhuacai@kernel.org \
    --cc=christophe.leroy@csgroup.eu \
    --cc=davem@davemloft.net \
    --cc=ddutile@redhat.com \
    --cc=deller@gmx.de \
    --cc=dinguyen@kernel.org \
    --cc=echanude@redhat.com \
    --cc=hca@linux.ibm.com \
    --cc=kent.overstreet@linux.dev \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mips@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-modules@vger.kernel.org \
    --cc=linux-parisc@vger.kernel.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=linux-s390@vger.kernel.org \
    --cc=linux-trace-kernel@vger.kernel.org \
    --cc=linux@armlinux.org.uk \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=loongarch@lists.linux.dev \
    --cc=mark.rutland@arm.com \
    --cc=mcgrof@kernel.org \
    --cc=mpe@ellerman.id.au \
    --cc=nadav.amit@gmail.com \
    --cc=netdev@vger.kernel.org \
    --cc=palmer@dabbelt.com \
    --cc=puranjay12@gmail.com \
    --cc=rick.p.edgecombe@intel.com \
    --cc=rostedt@goodmis.org \
    --cc=rppt@kernel.org \
    --cc=song@kernel.org \
    --cc=sparclinux@vger.kernel.org \
    --cc=tglx@linutronix.de \
    --cc=tsbogend@alpha.franken.de \
    --cc=will@kernel.org \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).