[PATCH] kprobes: fix bug when probed on task and isr functions
[linux-2.6.git] / arch / ia64 / kernel / kprobes.c
index 4b1bd53..471086b 100644 (file)
@@ -95,6 +95,17 @@ static void __kprobes update_kprobe_inst_flag(uint template, uint  slot,
        p->ainsn.inst_flag = 0;
        p->ainsn.target_br_reg = 0;
 
+       /* Check for Break instruction
+        * Bits 37:40 Major opcode to be zero
+        * Bits 27:32 X6 to be zero
+        * Bits 32:35 X3 to be zero
+        */
+       if ((!major_opcode) && (!((kprobe_inst >> 27) & 0x1FF)) ) {
+               /* is a break instruction */
+               p->ainsn.inst_flag |= INST_FLAG_BREAK_INST;
+               return;
+       }
+
        if (bundle_encoding[template][slot] == B) {
                switch (major_opcode) {
                  case INDIRECT_CALL_OPCODE:
@@ -542,8 +553,11 @@ static void __kprobes prepare_ss(struct kprobe *p, struct pt_regs *regs)
        unsigned long bundle_addr = (unsigned long) &p->opcode.bundle;
        unsigned long slot = (unsigned long)p->addr & 0xf;
 
-       /* Update instruction pointer (IIP) and slot number (IPSR.ri) */
-       regs->cr_iip = bundle_addr & ~0xFULL;
+       /* single step inline if break instruction */
+       if (p->ainsn.inst_flag == INST_FLAG_BREAK_INST)
+               regs->cr_iip = (unsigned long)p->addr & ~0xFULL;
+       else
+               regs->cr_iip = bundle_addr & ~0xFULL;
 
        if (slot > 2)
                slot = 0;
@@ -599,7 +613,9 @@ static int __kprobes pre_kprobes_handler(struct die_args *args)
        if (kprobe_running()) {
                p = get_kprobe(addr);
                if (p) {
-                       if (kprobe_status == KPROBE_HIT_SS) {
+                       if ( (kprobe_status == KPROBE_HIT_SS) &&
+                            (p->ainsn.inst_flag == INST_FLAG_BREAK_INST)) {
+                               ia64_psr(regs)->ss = 0;
                                unlock_kprobes();
                                goto no_kprobe;
                        }