From: Keshavamurthy Anil S <anil.s.keshavamurthy@intel.com>
Once the jprobe instrumented function returns, it executes a jprobe_break
which is a break instruction with __IA64_JPROBE_BREAK value. The current
patch checks for this break value, before assuming that jprobe instrumented
function just completed.
The previous code was not checking for this value and that was a bug.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
arch/ia64/kernel/kprobes.c | 10 +++++++---
1 files changed, 7 insertions(+), 3 deletions(-)
diff -puN arch/ia64/kernel/kprobes.c~kprobes-ia64-check-jprobe-break-before-handling arch/ia64/kernel/kprobes.c
--- 25/arch/ia64/kernel/kprobes.c~kprobes-ia64-check-jprobe-break-before-handling 2005-06-18 02:49:06.000000000 -0700
+++ 25-akpm/arch/ia64/kernel/kprobes.c 2005-06-18 02:49:06.000000000 -0700
@@ -419,10 +419,11 @@ static void prepare_ss(struct kprobe *p,
ia64_psr(regs)->ss = 1;
}
-static int pre_kprobes_handler(struct pt_regs *regs)
+static int pre_kprobes_handler(struct die_args *args)
{
struct kprobe *p;
int ret = 0;
+ struct pt_regs *regs = args->regs;
kprobe_opcode_t *addr = (kprobe_opcode_t *)instruction_pointer(regs);
preempt_disable();
@@ -437,7 +438,7 @@ static int pre_kprobes_handler(struct pt
}
arch_disarm_kprobe(p);
ret = 1;
- } else {
+ } else if (args->err == __IA64_BREAK_JPROBE) {
/*
* jprobe instrumented function just completed
*/
@@ -445,6 +446,9 @@ static int pre_kprobes_handler(struct pt
if (p->break_handler && p->break_handler(p, regs)) {
goto ss_probe;
}
+ } else {
+ /* Not our break */
+ goto no_kprobe;
}
}
@@ -515,7 +519,7 @@ int kprobe_exceptions_notify(struct noti
struct die_args *args = (struct die_args *)data;
switch(val) {
case DIE_BREAK:
- if (pre_kprobes_handler(args->regs))
+ if (pre_kprobes_handler(args))
return NOTIFY_STOP;
break;
case DIE_SS:
_