[PATCH] kprobe: fix resume execution on i386

Fix resume_execution() to handle iret and absolute jump opcode correctly on
i386.
Signed-off-by: NMasami Hiramatsu <hiramatu@sdl.hitachi.co.jp>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Yumiko Sugita <sugita@sdl.hitachi.co.jp>
Cc: Satoshi Oshima <soshima@redhat.com>
Cc: Hideo Aoki <haoki@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

arch/i386/kernel/kprobes.c

@@ -443,10 +443,11 @@ static void __kprobes resume_execution(struct kprobe *p,
 		*tos &= ~(TF_MASK | IF_MASK);
 		*tos |= kcb->kprobe_old_eflags;
 		break;
-	case 0xc3:		/* ret/lret */
-	case 0xcb:
-	case 0xc2:
+	case 0xc2:		/* iret/ret/lret */
+	case 0xc3:
 	case 0xca:
+	case 0xcb:
+	case 0xcf:
 	case 0xea:		/* jmp absolute -- eip is correct */
 		/* eip is already adjusted, no more changes required */
 		p->ainsn.boostable = 1;
@@ -454,10 +455,13 @@ static void __kprobes resume_execution(struct kprobe *p,
 	case 0xe8:		/* call relative - Fix return addr */
 		*tos = orig_eip + (*tos - copy_eip);
 		break;
+	case 0x9a:		/* call absolute -- same as call absolute, indirect */
+		*tos = orig_eip + (*tos - copy_eip);
+		goto no_change;
 	case 0xff:
 		if ((p->ainsn.insn[1] & 0x30) == 0x10) {
-			/* call absolute, indirect */
 			/*
+			 * call absolute, indirect
 			 * Fix return addr; eip is correct.
 			 * But this is not boostable
 			 */