diff --git a/src/mem/ruby/system/RubyPort.cc b/src/mem/ruby/system/RubyPort.cc
index 741a41023f..d1305c4fe6 100644
--- a/src/mem/ruby/system/RubyPort.cc
+++ b/src/mem/ruby/system/RubyPort.cc
@@ -565,7 +565,7 @@ RubyPort::MemResponsePort::hitCallback(PacketPtr pkt)
         // We must check device memory first in case it overlaps with the
         // system memory range.
         if (ruby_port->system->isDeviceMemAddr(pkt)) {
-            auto dmem = ruby_port->system->getDeviceMemory(pkt->requestorId());
+            auto dmem = ruby_port->system->getDeviceMemory(pkt);
             dmem->access(pkt);
         } else if (ruby_port->system->isMemAddr(pkt->getAddr())) {
             rs->getPhysMem()->access(pkt);
diff --git a/src/sim/system.cc b/src/sim/system.cc
index 3c244d822d..04dce5e9fc 100644
--- a/src/sim/system.cc
+++ b/src/sim/system.cc
@@ -378,26 +378,34 @@ System::isMemAddr(Addr addr) const
 void
 System::addDeviceMemory(RequestorID requestor_id, AbstractMemory *deviceMemory)
 {
-    if (!deviceMemMap.count(requestor_id)) {
-        deviceMemMap.insert(std::make_pair(requestor_id, deviceMemory));
-    }
+    deviceMemMap[requestor_id].push_back(deviceMemory);
 }
 
 bool
-System::isDeviceMemAddr(PacketPtr pkt) const
+System::isDeviceMemAddr(const PacketPtr& pkt) const
 {
-    const RequestorID& id = pkt->requestorId();
+    if (!deviceMemMap.count(pkt->requestorId())) {
+        return false;
+    }
 
-    return (deviceMemMap.count(id) &&
-            deviceMemMap.at(id)->getAddrRange().contains(pkt->getAddr()));
+    return (getDeviceMemory(pkt) != nullptr);
 }
 
 AbstractMemory *
-System::getDeviceMemory(RequestorID id) const
+System::getDeviceMemory(const PacketPtr& pkt) const
 {
-    panic_if(!deviceMemMap.count(id),
-             "No device memory found for RequestorID %d\n", id);
-    return deviceMemMap.at(id);
+    const RequestorID& rid = pkt->requestorId();
+
+    panic_if(!deviceMemMap.count(rid),
+             "No device memory found for Requestor %d\n", rid);
+
+    for (auto& mem : deviceMemMap.at(rid)) {
+        if (pkt->getAddrRange().isSubset(mem->getAddrRange())) {
+            return mem;
+        }
+    }
+
+    return nullptr;
 }
 
 void
diff --git a/src/sim/system.hh b/src/sim/system.hh
index 09798c3855..66e138e39f 100644
--- a/src/sim/system.hh
+++ b/src/sim/system.hh
@@ -108,7 +108,8 @@ class System : public SimObject, public PCEventScope
     SystemPort _systemPort;
 
     // Map of memory address ranges for devices with their own backing stores
-    std::unordered_map<RequestorID, AbstractMemory *> deviceMemMap;
+    std::unordered_map<RequestorID, std::vector<AbstractMemory *>>
+        deviceMemMap;
 
   public:
 
@@ -371,12 +372,12 @@ class System : public SimObject, public PCEventScope
      * of the packet match an address range of a device corresponding to the
      * RequestorId of the request.
      */
-    bool isDeviceMemAddr(PacketPtr pkt) const;
+    bool isDeviceMemAddr(const PacketPtr& pkt) const;
 
     /**
      * Return a pointer to the device memory.
      */
-    AbstractMemory *getDeviceMemory(RequestorID _id) const;
+    AbstractMemory *getDeviceMemory(const PacketPtr& pkt) const;
 
     /*
      * Return the list of address ranges backed by a shadowed ROM.