[PATCH -tip v3 2/7] kprobes: Remove jprobe API implementation

Masami Hiramatsu
2018-05-16T23:58:02Z

Remove jprobe API implementations and test cases for
those APIs which is no more used.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
Changes in v3:
- Remove test cases.
---
include/linux/kprobes.h | 3 --
kernel/kprobes.c | 78 +--------------------------------------
kernel/test_kprobes.c | 94 -----------------------------------------------
3 files changed, 1 insertion(+), 174 deletions(-)

diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 9440a2fc8893..b520baa65682 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -389,9 +389,6 @@ 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);
-int setjmp_pre_handler(struct kprobe *, struct pt_regs *);
-int longjmp_break_handler(struct kprobe *, struct pt_regs *);
-void jprobe_return(void);
unsigned long arch_deref_entry_point(void *);

int register_kretprobe(struct kretprobe *rp);
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index ea619021d901..69de130595f7 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1272,7 +1272,7 @@ NOKPROBE_SYMBOL(cleanup_rp_inst);

/*
* Add the new probe to ap->list. Fail if this is the
-* second jprobe at the address - two jprobes can't coexist
+* second break_handler at the address
*/
static int add_new_kprobe(struct kprobe *ap, struct kprobe *p)
{
@@ -1812,77 +1812,6 @@ unsigned long __weak arch_deref_entry_point(void *entry)
return (unsigned long)entry;
}

-#if 0
-int register_jprobes(struct jprobe **jps, int num)
-{
- int ret = 0, i;
-
- if (num <= 0)
- return -EINVAL;
-
- for (i = 0; i < num; i++) {
- ret = register_jprobe(jps[i]);
-
- if (ret < 0) {
- if (i > 0)
- unregister_jprobes(jps, i);
- break;
- }
- }
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(register_jprobes);
-
-int register_jprobe(struct jprobe *jp)
-{
- unsigned long addr, offset;
- struct kprobe *kp = &jp->kp;
-
- /*
- * Verify probepoint as well as the jprobe handler are
- * valid function entry points.
- */
- addr = arch_deref_entry_point(jp->entry);
-
- if (kallsyms_lookup_size_offset(addr, NULL, &offset) && offset == 0 &&
- kprobe_on_func_entry(kp->addr, kp->symbol_name, kp->offset)) {
- kp->pre_handler = setjmp_pre_handler;
- kp->break_handler = longjmp_break_handler;
- return register_kprobe(kp);
- }
-
- return -EINVAL;
-}
-EXPORT_SYMBOL_GPL(register_jprobe);
-
-void unregister_jprobe(struct jprobe *jp)
-{
- unregister_jprobes(&jp, 1);
-}
-EXPORT_SYMBOL_GPL(unregister_jprobe);
-
-void unregister_jprobes(struct jprobe **jps, int num)
-{
- int i;
-
- if (num <= 0)
- return;
- mutex_lock(&kprobe_mutex);
- for (i = 0; i < num; i++)
- if (__unregister_kprobe_top(&jps[i]->kp) < 0)
- jps[i]->kp.addr = NULL;
- mutex_unlock(&kprobe_mutex);
-
- synchronize_sched();
- for (i = 0; i < num; i++) {
- if (jps[i]->kp.addr)
- __unregister_kprobe_bottom(&jps[i]->kp);
- }
-}
-EXPORT_SYMBOL_GPL(unregister_jprobes);
-#endif
-
#ifdef CONFIG_KRETPROBES
/*
* This kprobe pre_handler is registered with every kretprobe. When probe
@@ -2329,8 +2258,6 @@ static void report_probe(struct seq_file *pi, struct kprobe *p,

if (p->pre_handler == pre_handler_kretprobe)
kprobe_type = "r";
- else if (p->pre_handler == setjmp_pre_handler)
- kprobe_type = "j";
else
kprobe_type = "k";

@@ -2637,6 +2564,3 @@ late_initcall(debugfs_kprobe_init);
#endif /* CONFIG_DEBUG_FS */

module_init(init_kprobes);
-
-/* defined in arch/.../kernel/kprobes.c */
-EXPORT_SYMBOL_GPL(jprobe_return);
diff --git a/kernel/test_kprobes.c b/kernel/test_kprobes.c
index dd53e354f630..7bca480151b0 100644
--- a/kernel/test_kprobes.c
+++ b/kernel/test_kprobes.c
@@ -162,90 +162,6 @@ static int test_kprobes(void)

}

-#if 0
-static u32 jph_val;
-
-static u32 j_kprobe_target(u32 value)
-{
- if (preemptible()) {
- handler_errors++;
- pr_err("jprobe-handler is preemptible\n");
- }
- if (value != rand1) {
- handler_errors++;
- pr_err("incorrect value in jprobe handler\n");
- }
-
- jph_val = rand1;
- jprobe_return();
- return 0;
-}
-
-static struct jprobe jp = {
- .entry = j_kprobe_target,
- .kp.symbol_name = "kprobe_target"
-};
-
-static int test_jprobe(void)
-{
- int ret;
-
- ret = register_jprobe(&jp);
- if (ret < 0) {
- pr_err("register_jprobe returned %d\n", ret);
- return ret;
- }
-
- ret = target(rand1);
- unregister_jprobe(&jp);
- if (jph_val == 0) {
- pr_err("jprobe handler not called\n");
- handler_errors++;
- }
-
- return 0;
-}
-
-static struct jprobe jp2 = {
- .entry = j_kprobe_target,
- .kp.symbol_name = "kprobe_target2"
-};
-
-static int test_jprobes(void)
-{
- int ret;
- struct jprobe *jps[2] = {&jp, &jp2};
-
- /* addr and flags should be cleard for reusing kprobe. */
- jp.kp.addr = NULL;
- jp.kp.flags = 0;
- ret = register_jprobes(jps, 2);
- if (ret < 0) {
- pr_err("register_jprobes returned %d\n", ret);
- return ret;
- }
-
- jph_val = 0;
- ret = target(rand1);
- if (jph_val == 0) {
- pr_err("jprobe handler not called\n");
- handler_errors++;
- }
-
- jph_val = 0;
- ret = target2(rand1);
- if (jph_val == 0) {
- pr_err("jprobe handler2 not called\n");
- handler_errors++;
- }
- unregister_jprobes(jps, 2);
-
- return 0;
-}
-#else
-#define test_jprobe() (0)
-#define test_jprobes() (0)
-#endif
#ifdef CONFIG_KRETPROBES
static u32 krph_val;

@@ -383,16 +299,6 @@ int init_test_probes(void)
if (ret < 0)
errors++;

- num_tests++;
- ret = test_jprobe();
- if (ret < 0)
- errors++;
-
- num_tests++;
- ret = test_jprobes();
- if (ret < 0)
- errors++;
-
#ifdef CONFIG_KRETPROBES
num_tests++;
ret = test_kretprobe();