[PATCH] kprobes: clean up resume_execute()

Clean up kprobe's resume_execute() for i386 arch.

Signed-off-by: Masami Hiramatsu <hiramatu@sdl.hitachi.co.jp>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 10 insertions, 16 deletions

diff --git a/arch/i386/kernel/kprobes.c b/arch/i386/kernel/kprobes.c
index 7a59050242a7..b40614f5afe2 100644
--- a/arch/i386/kernel/kprobes.c
+++ b/arch/i386/kernel/kprobes.c
@@ -362,10 +362,10 @@ static void __kprobes resume_execution(struct kprobe *p,
                 struct pt_regs *regs, struct kprobe_ctlblk *kcb)
 {
         unsigned long *tos = (unsigned long *)&regs->esp;
-        unsigned long next_eip = 0;
         unsigned long copy_eip = (unsigned long)p->ainsn.insn;
         unsigned long orig_eip = (unsigned long)p->addr;
 
+        regs->eflags &= ~TF_MASK;
         switch (p->ainsn.insn[0]) {
         case 0x9c:              /* pushfl */
                 *tos &= ~(TF_MASK | IF_MASK);
@@ -375,9 +375,9 @@ static void __kprobes resume_execution(struct kprobe *p,
         case 0xcb:
         case 0xc2:
         case 0xca:
-                regs->eflags &= ~TF_MASK;
-                /* eip is already adjusted, no more changes required*/
-                return;
+        case 0xea:              /* jmp absolute -- eip is correct */
+                /* eip is already adjusted, no more changes required */
+                goto no_change;
         case 0xe8:              /* call relative - Fix return addr */
                 *tos = orig_eip + (*tos - copy_eip);
                 break;
@@ -385,27 +385,21 @@ static void __kprobes resume_execution(struct kprobe *p,
                 if ((p->ainsn.insn[1] & 0x30) == 0x10) {
                         /* call absolute, indirect */
                         /* Fix return addr; eip is correct. */
-                        next_eip = regs->eip;
                         *tos = orig_eip + (*tos - copy_eip);
+                        goto no_change;
                 } else if (((p->ainsn.insn[1] & 0x31) == 0x20) ||       /* jmp near, absolute indirect */
                            ((p->ainsn.insn[1] & 0x31) == 0x21)) {       /* jmp far, absolute indirect */
                         /* eip is correct. */
-                        next_eip = regs->eip;
+                        goto no_change;
                 }
-                break;
-        case 0xea:              /* jmp absolute -- eip is correct */
-                next_eip = regs->eip;
-                break;
         default:
                 break;
         }
 
-        regs->eflags &= ~TF_MASK;
-        if (next_eip) {
-                regs->eip = next_eip;
-        } else {
-                regs->eip = orig_eip + (regs->eip - copy_eip);
-        }
+        regs->eip = orig_eip + (regs->eip - copy_eip);
+
+no_change:
+        return;
 }
 
 /*