[PATCH -tip v4 02/12] kprobes: treewide: Replace arch_deref_entry_point() with dereference_function_

Masami Hiramatsu
2021-03-22T06:40:07Z

Replace arch_deref_entry_point() with dereference_function_descriptor()
because those are doing same thing.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
arch/ia64/kernel/kprobes.c | 5 -----
arch/powerpc/kernel/kprobes.c | 11 -----------
include/linux/kprobes.h | 1 -
kernel/kprobes.c | 7 +------
lib/error-inject.c | 3 ++-
5 files changed, 3 insertions(+), 24 deletions(-)

diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c
index 006fbc1d7ae9..15871eb170c0 100644
--- a/arch/ia64/kernel/kprobes.c
+++ b/arch/ia64/kernel/kprobes.c
@@ -907,11 +907,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
return ret;
}

-unsigned long arch_deref_entry_point(void *entry)
-{
- return ((struct fnptr *)entry)->ip;
-}
-
static struct kprobe trampoline_p = {
.pre_handler = trampoline_probe_handler
};
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index 01ab2163659e..eb0460949e1b 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -539,17 +539,6 @@ int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
}
NOKPROBE_SYMBOL(kprobe_fault_handler);

-unsigned long arch_deref_entry_point(void *entry)
-{
-#ifdef PPC64_ELF_ABI_v1
- if (!kernel_text_address((unsigned long)entry))
- return ppc_global_function_entry(entry);
- else
-#endif
- return (unsigned long)entry;
-}
-NOKPROBE_SYMBOL(arch_deref_entry_point);
-
static struct kprobe trampoline_p = {
.addr = (kprobe_opcode_t *) &kretprobe_trampoline,
.pre_handler = trampoline_probe_handler
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 1883a4a9f16a..d65c041b5c22 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -390,7 +390,6 @@ int register_kprobe(struct kprobe *p);
void unregister_kprobe(struct kprobe *p);
int register_kprobes(struct kprobe **kps, int num);
void unregister_kprobes(struct kprobe **kps, int num);
-unsigned long arch_deref_entry_point(void *);

int register_kretprobe(struct kretprobe *rp);
void unregister_kretprobe(struct kretprobe *rp);
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 745f08fdd7a6..2913de07f4a3 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1856,11 +1856,6 @@ static struct notifier_block kprobe_exceptions_nb = {
.priority = 0x7fffffff /* we need to be notified first */
};

-unsigned long __weak arch_deref_entry_point(void *entry)
-{
- return (unsigned long)entry;
-}
-
#ifdef CONFIG_KRETPROBES

unsigned long __kretprobe_trampoline_handler(struct pt_regs *regs,
@@ -2324,7 +2319,7 @@ static int __init populate_kprobe_blacklist(unsigned long *start,
int ret;

for (iter = start; iter < end; iter++) {
- entry = arch_deref_entry_point((void *)*iter);
+ entry = (unsigned long)dereference_function_descriptor((void *)*iter);
ret = kprobe_add_ksym_blacklist(entry);
if (ret = -EINVAL)
continue;
diff --git a/lib/error-inject.c b/lib/error-inject.c
index c73651b15b76..f71875ac5f9f 100644
--- a/lib/error-inject.c
+++ b/lib/error-inject.c
@@ -8,6 +8,7 @@
#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/slab.h>
+#include <asm/sections.h>

/* Whitelist of symbols that can be overridden for error injection. */
static LIST_HEAD(error_injection_list);
@@ -64,7 +65,7 @@ static void populate_error_injection_list(struct error_injection_entry *start,

mutex_lock(&ei_mutex);
for (iter = start; iter < end; iter++) {
- entry = arch_deref_entry_point((void *)iter->addr);
+ entry = (unsigned long)dereference_function_descriptor((void *)iter->addr);

if (!kernel_text_address(entry) ||
!kallsyms_lookup_size_offset(entry, &size, &offset)) {