diff --git a/src/dev/arm/Gic.py b/src/dev/arm/Gic.py
index 41d602b86a..6fd8eb235f 100644
--- a/src/dev/arm/Gic.py
+++ b/src/dev/arm/Gic.py
@@ -315,6 +315,15 @@ class Gicv3(BaseGic):
 
     gicv4 = Param.Bool(False, "GIC is GICv4 compatible")
 
+    reserved_is_res0 = Param.Bool(
+        True,
+        "According to the GIC specification (IHI0069) "
+        "reserved addresses in the GIC memory map are treated as RES0. "
+        "We allow to disable this behaviour and panic instead "
+        "(reserved_res0 = False) to catch development bugs "
+        "(in gem5 and in the guest SW)",
+    )
+
     def interruptCells(self, int_type, int_num, int_trigger, partition=None):
         """
         Interupt cells generation helper:
diff --git a/src/dev/arm/gic_v3.hh b/src/dev/arm/gic_v3.hh
index 2ea6a98b3b..7adb1d0f3f 100644
--- a/src/dev/arm/gic_v3.hh
+++ b/src/dev/arm/gic_v3.hh
@@ -167,6 +167,17 @@ class Gicv3 : public BaseGic, public Gicv3Registers
     Tick write(PacketPtr pkt) override;
     bool supportsVersion(GicVersion version) override;
 
+    template<typename... Args>
+    void
+    reserved(const char* fmt, Args... args) const
+    {
+        if (params().reserved_is_res0) {
+            warn(fmt, args...);
+        } else {
+            panic(fmt, args...);
+        }
+    }
+
   public:
 
     Gicv3(const Params &p);
diff --git a/src/dev/arm/gic_v3_distributor.cc b/src/dev/arm/gic_v3_distributor.cc
index 1cb485c5f5..af306929ff 100644
--- a/src/dev/arm/gic_v3_distributor.cc
+++ b/src/dev/arm/gic_v3_distributor.cc
@@ -505,8 +505,8 @@ Gicv3Distributor::read(Addr addr, size_t size, bool is_secure_access)
         return 0; // RES0
 
       default:
-        panic("Gicv3Distributor::read(): invalid offset %#x\n", addr);
-        break;
+        gic->reserved("Gicv3Distributor::read(): invalid offset %#x\n", addr);
+        return 0; // RES0
     }
 }
 
@@ -999,7 +999,7 @@ Gicv3Distributor::write(Addr addr, uint64_t data, size_t size,
       }
 
       default:
-        panic("Gicv3Distributor::write(): invalid offset %#x\n", addr);
+        gic->reserved("Gicv3Distributor::write(): invalid offset %#x\n", addr);
         break;
     }
 }
diff --git a/src/dev/arm/gic_v3_redistributor.cc b/src/dev/arm/gic_v3_redistributor.cc
index e4380ef6f0..67d6e42e6b 100644
--- a/src/dev/arm/gic_v3_redistributor.cc
+++ b/src/dev/arm/gic_v3_redistributor.cc
@@ -377,8 +377,8 @@ Gicv3Redistributor::read(Addr addr, size_t size, bool is_secure_access)
         return 0;
 
       default:
-        panic("Gicv3Redistributor::read(): invalid offset %#x\n", addr);
-        break;
+        gic->reserved("Gicv3Redistributor::read(): invalid offset %#x\n", addr);
+        return 0; // RES0
     }
 }
 
@@ -704,7 +704,7 @@ Gicv3Redistributor::write(Addr addr, uint64_t data, size_t size,
       }
 
       default:
-        panic("Gicv3Redistributor::write(): invalid offset %#x\n", addr);
+        gic->reserved("Gicv3Redistributor::write(): invalid offset %#x\n", addr);
         break;
     }
 }