[PATCH] kretprobe spinlock deadlock patch

[net-next-2.6.git] / arch / powerpc / kernel / kprobes.c

diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index 46d2fd0e57895fe71c300e74da3aeb4eb98f7cf5..7b8d12b9026c48487fbad3a4b83ca682108db260 100644 (file)
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -260,11 +260,12 @@ void kretprobe_trampoline_holder(void)
 int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
 {
        struct kretprobe_instance *ri = NULL;
-       struct hlist_head *head;
+       struct hlist_head *head, empty_rp;
        struct hlist_node *node, *tmp;
        unsigned long flags, orig_ret_address = 0;
        unsigned long trampoline_address =(unsigned long)&kretprobe_trampoline;
 
+       INIT_HLIST_HEAD(&empty_rp);
        spin_lock_irqsave(&kretprobe_lock, flags);
        head = kretprobe_inst_table_head(current);
 
@@ -290,7 +291,7 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
                        ri->rp->handler(ri, regs);
 
                orig_ret_address = (unsigned long)ri->ret_addr;
-               recycle_rp_inst(ri);
+               recycle_rp_inst(ri, &empty_rp);
 
                if (orig_ret_address != trampoline_address)
                        /*
@@ -308,6 +309,10 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
        spin_unlock_irqrestore(&kretprobe_lock, flags);
        preempt_enable_no_resched();
 
+       hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) {
+               hlist_del(&ri->hlist);
+               kfree(ri);
+       }
        /*
         * By returning a non-zero value, we are telling
         * kprobe_handler() that we don't want the post_handler