From 59e87cdcd268daa85c0732e147c59e0c1bacd704 Mon Sep 17 00:00:00 2001
From: Masami Hiramatsu <mhiramat@redhat.com>
Date: Wed, 30 Jan 2008 13:32:02 +0100
Subject: [PATCH] x86: move deeply indented code to reenter_kprobe
Move some deeply indented code related to re-entrance processing
from kprobe_handler() to reenter_kprobe().
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/kernel/kprobes.c | 46 +++++++++++++++++++--------------------
1 file changed, 23 insertions(+), 23 deletions(-)
diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c
index 7dd918633c3..4e33329ce8a 100644
--- a/arch/x86/kernel/kprobes.c
+++ b/arch/x86/kernel/kprobes.c
@@ -432,14 +432,32 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
* within the handler. We save the original kprobes variables and just single
* step on the instruction of the new probe without calling any user handlers.
*/
-static void __kprobes reenter_kprobe(struct kprobe *p, struct pt_regs *regs,
- struct kprobe_ctlblk *kcb)
+static int __kprobes reenter_kprobe(struct kprobe *p, struct pt_regs *regs,
+ struct kprobe_ctlblk *kcb)
{
+ if (kcb->kprobe_status == KPROBE_HIT_SS &&
+ *p->ainsn.insn == BREAKPOINT_INSTRUCTION) {
+ regs->flags &= ~X86_EFLAGS_TF;
+ regs->flags |= kcb->kprobe_saved_flags;
+ return 0;
+#ifdef CONFIG_X86_64
+ } else if (kcb->kprobe_status == KPROBE_HIT_SSDONE) {
+ /* TODO: Provide re-entrancy from post_kprobes_handler() and
+ * avoid exception stack corruption while single-stepping on
+ * the instruction of the new probe.
+ */
+ arch_disarm_kprobe(p);
+ regs->ip = (unsigned long)p->addr;
+ reset_current_kprobe();
+ return 1;
+#endif
+ }
save_previous_kprobe(kcb);
set_current_kprobe(p, regs, kcb);
kprobes_inc_nmissed_count(p);
prepare_singlestep(p, regs);
kcb->kprobe_status = KPROBE_REENTER;
+ return 1;
}
/*
@@ -466,27 +484,9 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
if (kprobe_running()) {
p = get_kprobe(addr);
if (p) {
- if (kcb->kprobe_status == KPROBE_HIT_SS &&
- *p->ainsn.insn == BREAKPOINT_INSTRUCTION) {
- regs->flags &= ~X86_EFLAGS_TF;
- regs->flags |= kcb->kprobe_saved_flags;
- goto no_kprobe;
-#ifdef CONFIG_X86_64
- } else if (kcb->kprobe_status == KPROBE_HIT_SSDONE) {
- /* TODO: Provide re-entrancy from
- * post_kprobes_handler() and avoid exception
- * stack corruption while single-stepping on
- * the instruction of the new probe.
- */
- arch_disarm_kprobe(p);
- regs->ip = (unsigned long)p->addr;
- reset_current_kprobe();
- ret = 1;
- goto no_kprobe;
-#endif
- }
- reenter_kprobe(p, regs, kcb);
- return 1;
+ ret = reenter_kprobe(p, regs, kcb);
+ if (kcb->kprobe_status == KPROBE_REENTER)
+ return 1;
} else {
if (*addr != BREAKPOINT_INSTRUCTION) {
/* The breakpoint instruction was removed by
--
2.41.3