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Diffstat (limited to 'arch/sparc/kernel/kprobes.c')
-rw-r--r--arch/sparc/kernel/kprobes.c80
1 files changed, 9 insertions, 71 deletions
diff --git a/arch/sparc/kernel/kprobes.c b/arch/sparc/kernel/kprobes.c
index dfbca2470536..191bbaca9921 100644
--- a/arch/sparc/kernel/kprobes.c
+++ b/arch/sparc/kernel/kprobes.c
@@ -230,7 +230,7 @@ static unsigned long __kprobes relbranch_fixup(u32 insn, struct kprobe *p,
return regs->tnpc;
}
-/* If INSN is an instruction which writes it's PC location
+/* If INSN is an instruction which writes its PC location
* into a destination register, fix that up.
*/
static void __kprobes retpc_fixup(struct pt_regs *regs, u32 insn,
@@ -346,23 +346,6 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
case KPROBE_HIT_ACTIVE:
case KPROBE_HIT_SSDONE:
/*
- * We increment the nmissed count for accounting,
- * we can also use npre/npostfault count for accounting
- * these specific fault cases.
- */
- kprobes_inc_nmissed_count(cur);
-
- /*
- * We come here because instructions in the pre/post
- * handler caused the page_fault, this could happen
- * if handler tries to access user space by
- * copy_from_user(), get_user() etc. Let the
- * user-specified handler try to fix it first.
- */
- if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr))
- return 1;
-
- /*
* In case the user-specified fault handler returned
* zero, try to fix up.
*/
@@ -453,10 +436,11 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
struct pt_regs *regs)
{
ri->ret_addr = (kprobe_opcode_t *)(regs->u_regs[UREG_RETPC] + 8);
+ ri->fp = NULL;
/* Replace the return addr with trampoline addr */
regs->u_regs[UREG_RETPC] =
- ((unsigned long)kretprobe_trampoline) - 8;
+ ((unsigned long)__kretprobe_trampoline) - 8;
}
/*
@@ -465,58 +449,12 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
static int __kprobes trampoline_probe_handler(struct kprobe *p,
struct pt_regs *regs)
{
- struct kretprobe_instance *ri = NULL;
- struct hlist_head *head, empty_rp;
- struct hlist_node *tmp;
- unsigned long flags, orig_ret_address = 0;
- unsigned long trampoline_address =(unsigned long)&kretprobe_trampoline;
-
- INIT_HLIST_HEAD(&empty_rp);
- kretprobe_hash_lock(current, &head, &flags);
+ unsigned long orig_ret_address = 0;
- /*
- * It is possible to have multiple instances associated with a given
- * task either because an multiple functions in the call path
- * have a return probe installed on them, and/or more than one return
- * return probe was registered for a target function.
- *
- * We can handle this because:
- * - instances are always inserted at the head of the list
- * - when multiple return probes are registered for the same
- * function, the first instance's ret_addr will point to the
- * real return address, and all the rest will point to
- * kretprobe_trampoline
- */
- hlist_for_each_entry_safe(ri, tmp, head, hlist) {
- if (ri->task != current)
- /* another task is sharing our hash bucket */
- continue;
-
- if (ri->rp && ri->rp->handler)
- ri->rp->handler(ri, regs);
-
- orig_ret_address = (unsigned long)ri->ret_addr;
- recycle_rp_inst(ri, &empty_rp);
-
- if (orig_ret_address != trampoline_address)
- /*
- * This is the real return address. Any other
- * instances associated with this task are for
- * other calls deeper on the call stack
- */
- break;
- }
-
- kretprobe_assert(ri, orig_ret_address, trampoline_address);
+ orig_ret_address = __kretprobe_trampoline_handler(regs, NULL);
regs->tpc = orig_ret_address;
regs->tnpc = orig_ret_address + 4;
- kretprobe_hash_unlock(current, &flags);
-
- hlist_for_each_entry_safe(ri, 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
@@ -527,13 +465,13 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p,
static void __used kretprobe_trampoline_holder(void)
{
- asm volatile(".global kretprobe_trampoline\n"
- "kretprobe_trampoline:\n"
+ asm volatile(".global __kretprobe_trampoline\n"
+ "__kretprobe_trampoline:\n"
"\tnop\n"
"\tnop\n");
}
static struct kprobe trampoline_p = {
- .addr = (kprobe_opcode_t *) &kretprobe_trampoline,
+ .addr = (kprobe_opcode_t *) &__kretprobe_trampoline,
.pre_handler = trampoline_probe_handler
};
@@ -544,7 +482,7 @@ int __init arch_init_kprobes(void)
int __kprobes arch_trampoline_kprobe(struct kprobe *p)
{
- if (p->addr == (kprobe_opcode_t *)&kretprobe_trampoline)
+ if (p->addr == (kprobe_opcode_t *)&__kretprobe_trampoline)
return 1;
return 0;