The patch titled
Subject: kprobes: remove dependency on CONFIG_MODULES
has been added to the -mm mm-unstable branch. Its filename is
kprobes-remove-dependency-on-config_modules.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kprobes-remove-dependency-on-config_modules.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Mike Rapoport (IBM)" <rppt@xxxxxxxxxx>
Subject: kprobes: remove dependency on CONFIG_MODULES
Date: Mon, 18 Sep 2023 10:29:54 +0300
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.
Link: https://lkml.kernel.org/r/20230918072955.2507221-13-rppt@xxxxxxxxxx
Signed-off-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
Cc: Björn Töpel <bjorn@xxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: Dinh Nguyen <dinguyen@xxxxxxxxxx>
Cc: Heiko Carstens <hca@xxxxxxxxxxxxx>
Cc: Helge Deller <deller@xxxxxx>
Cc: Huacai Chen <chenhuacai@xxxxxxxxxx>
Cc: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Nadav Amit <nadav.amit@xxxxxxxxx>
Cc: "Naveen N. Rao" <naveen.n.rao@xxxxxxxxxxxxx>
Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx>
Cc: Puranjay Mohan <puranjay12@xxxxxxxxx>
Cc: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
Cc: Russell King (Oracle) <linux@xxxxxxxxxxxxxxx>
Cc: Song Liu <song@xxxxxxxxxx>
Cc: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/Kconfig | 2 -
kernel/kprobes.c | 43 +++++++++++++++++++---------------
kernel/trace/trace_kprobe.c | 11 ++++++++
3 files changed, 37 insertions(+), 19 deletions(-)
--- a/arch/Kconfig~kprobes-remove-dependency-on-config_modules
+++ a/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
--- a/kernel/kprobes.c~kprobes-remove-dependency-on-config_modules
+++ a/kernel/kprobes.c
@@ -1580,6 +1580,7 @@ static int check_kprobe_address_safe(str
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(str
ret = -ENOENT;
}
}
+#endif
+
out:
preempt_enable();
jump_label_unlock();
@@ -2495,24 +2498,6 @@ int kprobe_add_area_blacklist(unsigned l
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)
{
@@ -2577,6 +2562,25 @@ static int __init populate_kprobe_blackl
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;
@@ -2678,6 +2682,7 @@ static struct notifier_block kprobe_modu
.notifier_call = kprobes_module_callback,
.priority = 0
};
+#endif
void kprobe_free_init_mem(void)
{
@@ -2737,8 +2742,10 @@ 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();
--- a/kernel/trace/trace_kprobe.c~kprobes-remove-dependency-on-config_modules
+++ a/kernel/trace/trace_kprobe.c
@@ -111,6 +111,7 @@ static nokprobe_inline bool trace_kprobe
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
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 @@ end:
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_kprob
.notifier_call = trace_kprobe_module_callback,
.priority = 1 /* Invoked after kprobe module callback */
};
+#endif
static int __trace_kprobe_create(int argc, const char *argv[])
{
@@ -1810,8 +1819,10 @@ static __init int init_kprobe_trace_earl
if (ret)
return ret;
+#ifdef CONFIG_MODULES
if (register_module_notifier(&trace_kprobe_module_nb))
return -EINVAL;
+#endif
return 0;
}
_
Patches currently in -mm which might be from rppt@xxxxxxxxxx are
nios2-define-virtual-address-space-for-modules.patch
mm-introduce-execmem_text_alloc-and-execmem_free.patch
mm-execmem-arch-convert-simple-overrides-of-module_alloc-to-execmem.patch
mm-execmem-arch-convert-remaining-overrides-of-module_alloc-to-execmem.patch
modules-execmem-drop-module_alloc.patch
mm-execmem-introduce-execmem_data_alloc.patch
arm64-execmem-extend-execmem_params-for-generated-code-allocations.patch
riscv-extend-execmem_params-for-generated-code-allocations.patch
powerpc-extend-execmem_params-for-kprobes-allocations.patch
arch-make-execmem-setup-available-regardless-of-config_modules.patch
x86-ftrace-enable-dynamic-ftrace-without-config_modules.patch
kprobes-remove-dependency-on-config_modules.patch
bpf-remove-config_bpf_jit-dependency-on-config_modules-of.patch
