cpu: fix exec tracing memory corruption bug

Accessing traceData (to call setAddress() and/or setData())
after initiating a timing translation was causing crashes,
since a failed translation could delete the traceData
object before returning.

It turns out that there was never a need to access traceData
after initiating the translation, as the traced data was
always available earlier; this ordering was merely
historical.  Furthermore, traceData->setAddress() and
traceData->setData() were being called both from the CPU
model and the ISA definition, often redundantly.

This patch standardizes all setAddress and setData calls
for memory instructions to be in the CPU models and not
in the ISA definition.  It also moves those calls above
the translation calls to eliminate the crashes.

4 files changed, 34 insertions, 28 deletions

diff --git a/src/cpu/simple/atomic.cc b/src/cpu/simple/atomic.cc
index 05b4ca3e2..7740434d8 100644
--- a/src/cpu/simple/atomic.cc
+++ b/src/cpu/simple/atomic.cc
@@ -451,6 +451,7 @@ AtomicSimpleCPU::write(T data, Addr addr, unsigned flags, uint64_t *res)
 
     if (traceData) {
         traceData->setAddr(addr);
+        traceData->setData(data);
     }
 
     //The block size of our peer.
@@ -530,12 +531,6 @@ AtomicSimpleCPU::write(T data, Addr addr, unsigned flags, uint64_t *res)
         //stop now.
         if (fault != NoFault || secondAddr <= addr)
         {
-            // If the write needs to have a fault on the access, consider
-            // calling changeStatus() and changing it to "bad addr write"
-            // or something.
-            if (traceData) {
-                traceData->setData(gtoh(data));
-            }
             if (req->isLocked() && fault == NoFault) {
                 assert(locked);
                 locked = false;
diff --git a/src/cpu/simple/base.cc b/src/cpu/simple/base.cc
index 0104e1b1f..17ba6a10b 100644
--- a/src/cpu/simple/base.cc
+++ b/src/cpu/simple/base.cc
@@ -205,6 +205,27 @@ change_thread_state(ThreadID tid, int activate, int priority)
 {
 }
 
+void
+BaseSimpleCPU::prefetch(Addr addr, unsigned flags)
+{
+    if (traceData) {
+        traceData->setAddr(addr);
+    }
+
+    // need to do this...
+}
+
+void
+BaseSimpleCPU::writeHint(Addr addr, int size, unsigned flags)
+{
+    if (traceData) {
+        traceData->setAddr(addr);
+    }
+
+    // need to do this...
+}
+
+
 Fault
 BaseSimpleCPU::copySrcTranslate(Addr src)
 {
diff --git a/src/cpu/simple/base.hh b/src/cpu/simple/base.hh
index 39961fb88..87e211521 100644
--- a/src/cpu/simple/base.hh
+++ b/src/cpu/simple/base.hh
@@ -232,16 +232,8 @@ class BaseSimpleCPU : public BaseCPU
     Addr getEA()        { panic("BaseSimpleCPU::getEA() not implemented\n");
         M5_DUMMY_RETURN}
 
-    void prefetch(Addr addr, unsigned flags)
-    {
-        // need to do this...
-    }
-
-    void writeHint(Addr addr, int size, unsigned flags)
-    {
-        // need to do this...
-    }
-
+    void prefetch(Addr addr, unsigned flags);
+    void writeHint(Addr addr, int size, unsigned flags);
 
     Fault copySrcTranslate(Addr src);
 
diff --git a/src/cpu/simple/timing.cc b/src/cpu/simple/timing.cc
index 221cb0d0d..7583c09e6 100644
--- a/src/cpu/simple/timing.cc
+++ b/src/cpu/simple/timing.cc
@@ -426,6 +426,10 @@ TimingSimpleCPU::read(Addr addr, T &data, unsigned flags)
     int data_size = sizeof(T);
     BaseTLB::Mode mode = BaseTLB::Read;
 
+    if (traceData) {
+        traceData->setAddr(addr);
+    }
+
     RequestPtr req  = new Request(asid, addr, data_size,
                                   flags, pc, _cpuId, tid);
 
@@ -460,11 +464,6 @@ TimingSimpleCPU::read(Addr addr, T &data, unsigned flags)
         thread->dtb->translateTiming(req, tc, translation, mode);
     }
 
-    if (traceData) {
-        traceData->setData(data);
-        traceData->setAddr(addr);
-    }
-
     return NoFault;
 }
 
@@ -548,6 +547,11 @@ TimingSimpleCPU::write(T data, Addr addr, unsigned flags, uint64_t *res)
     int data_size = sizeof(T);
     BaseTLB::Mode mode = BaseTLB::Write;
 
+    if (traceData) {
+        traceData->setAddr(addr);
+        traceData->setData(data);
+    }
+
     RequestPtr req = new Request(asid, addr, data_size,
                                  flags, pc, _cpuId, tid);
 
@@ -584,13 +588,7 @@ TimingSimpleCPU::write(T data, Addr addr, unsigned flags, uint64_t *res)
         thread->dtb->translateTiming(req, tc, translation, mode);
     }
 
-    if (traceData) {
-        traceData->setAddr(req->getVaddr());
-        traceData->setData(data);
-    }
-
-    // If the write needs to have a fault on the access, consider calling
-    // changeStatus() and changing it to "bad addr write" or something.
+    // Translation faults will be returned via finishTranslation()
     return NoFault;
 }