From bbd23554f998950026e82b5dba9d18140b96c8e3 Mon Sep 17 00:00:00 2001
From: Vyacheslav Cherkashin <v.cherkashin@samsung.com>
Date: Wed, 29 Aug 2012 14:37:30 +0400
Subject: [PATCH] fix miss events (recursion handling disabled) 	recursing?!

---
 kprobe/arch/asm-arm/dbi_kprobes.c |  9 +++++----
 kprobe/dbi_insn_slots.c           | 14 +++++++-------
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/kprobe/arch/asm-arm/dbi_kprobes.c b/kprobe/arch/asm-arm/dbi_kprobes.c
index e45e1fd..73ea5f0 100644
--- a/kprobe/arch/asm-arm/dbi_kprobes.c
+++ b/kprobe/arch/asm-arm/dbi_kprobes.c
@@ -715,7 +715,7 @@ void save_previous_kprobe (struct kprobe_ctlblk *kcb, struct kprobe *cur_p)
 
 void restore_previous_kprobe (struct kprobe_ctlblk *kcb)
 {
-	__get_cpu_var (current_kprobe) = kcb->prev_kprobe.kp;
+	set_current_kprobe(kcb->prev_kprobe.kp, NULL, NULL);
 	kcb->kprobe_status = kcb->prev_kprobe.status;
 	kcb->prev_kprobe.kp = NULL;
 	kcb->prev_kprobe.status = 0;
@@ -1090,7 +1090,8 @@ int kprobe_handler (struct pt_regs *regs)
 		pid = current->tgid;
 	}
 	/* Check we're not actually recursing */
-	if (kprobe_running ())
+	// TODO: handling of recursion is disabled
+	if (0 && kprobe_running ())
 	{
 		DBPRINTF ("lock???");
 		p = get_kprobe (addr, pid, current);
@@ -1149,7 +1150,7 @@ int kprobe_handler (struct pt_regs *regs)
 				}
 			}
 			if(!p) {
-				p = __get_cpu_var (current_kprobe);
+				p = kprobe_running();
 				DBPRINTF ("kprobe_running !!! p = 0x%p p->break_handler = 0x%p", p, p->break_handler);
 				/*if (p->break_handler && p->break_handler(p, regs)) {
 				  DBPRINTF("kprobe_running !!! goto ss");
@@ -1293,7 +1294,7 @@ int setjmp_pre_handler (struct kprobe *p, struct pt_regs *regs)
 	entry_point_t entry;
 
 # ifdef REENTER
-	p = __get_cpu_var (current_kprobe);
+	p = kprobe_running();
 # endif
 
 	DBPRINTF ("pjp = 0x%p jp->entry = 0x%p", jp, jp->entry);
diff --git a/kprobe/dbi_insn_slots.c b/kprobe/dbi_insn_slots.c
index cce3c62..de979af 100644
--- a/kprobe/dbi_insn_slots.c
+++ b/kprobe/dbi_insn_slots.c
@@ -149,7 +149,7 @@ kprobe_opcode_t *get_insn_slot (struct task_struct *task, int atomic)
 	}
 
 retry:
-	hlist_for_each_entry (kip, pos, page_list, hlist)
+	hlist_for_each_entry_rcu(kip, pos, page_list, hlist)
 	{
 		if( !(!task || (kip->tgid == task->tgid)) )
 			continue;
@@ -211,7 +211,7 @@ retry:
 	kip->ngarbage = 0;
 	kip->tgid = task ? task->tgid : 0;
 	INIT_HLIST_NODE (&kip->hlist);
-	hlist_add_head (&kip->hlist, page_list);
+	hlist_add_head_rcu(&kip->hlist, page_list);
 	return kip->insns;
 }
 
@@ -231,11 +231,11 @@ int collect_one_slot (struct hlist_head *page_list, struct task_struct *task,
 		 * so as not to have to set it up again the
 		 * next time somebody inserts a probe.
 		 */
-		hlist_del (&kip->hlist);
+		hlist_del_rcu(&kip->hlist);
 		if (!task && hlist_empty (page_list))
 		{
 			INIT_HLIST_NODE (&kip->hlist);
-			hlist_add_head (&kip->hlist, page_list);
+			hlist_add_head_rcu(&kip->hlist, page_list);
 		}
 		else
 		{
@@ -272,7 +272,7 @@ int collect_one_slot (struct hlist_head *page_list, struct task_struct *task,
 int collect_garbage_slots (struct hlist_head *page_list, struct task_struct *task)
 {
 	struct kprobe_insn_page *kip;
-	struct hlist_node *pos, *next;
+	struct hlist_node *pos;
 	unsigned slots_per_page = INSNS_PER_PAGE;
 
 	/* Ensure no-one is preepmted on the garbages */
@@ -284,7 +284,7 @@ int collect_garbage_slots (struct hlist_head *page_list, struct task_struct *tas
 	else
 		slots_per_page = INSNS_PER_PAGE/KPROBES_TRAMP_LEN;
 
-	hlist_for_each_entry_safe (kip, pos, next, page_list, hlist)
+	hlist_for_each_entry_rcu(kip, pos, page_list, hlist)
 	{
 		int i;
 		if ((task && (kip->tgid != task->tgid)) || (kip->ngarbage == 0))
@@ -323,7 +323,7 @@ void free_insn_slot (struct hlist_head *page_list, struct task_struct *task, kpr
 	}
 
 	DBPRINTF("free_insn_slot: dirty %d, %p/%d", dirty, task, task?task->pid:0);
-	hlist_for_each_entry (kip, pos, page_list, hlist)
+	hlist_for_each_entry_rcu(kip, pos, page_list, hlist)
 	{
 		DBPRINTF("free_insn_slot: kip->insns=%p slot=%p", kip->insns, slot);
 		if ((kip->insns <= slot) && (slot < kip->insns + (INSNS_PER_PAGE * MAX_INSN_SIZE)))
-- 
2.7.4