diff --git a/lldb/test/API/functionalities/gdb_remote_client/TestGDBRemoteClient.py b/lldb/test/API/functionalities/gdb_remote_client/TestGDBRemoteClient.py
--- a/lldb/test/API/functionalities/gdb_remote_client/TestGDBRemoteClient.py
+++ b/lldb/test/API/functionalities/gdb_remote_client/TestGDBRemoteClient.py
@@ -9,8 +9,28 @@
 class TestGDBRemoteClient(GDBRemoteTestBase):
 
     class gPacketResponder(MockGDBServerResponder):
+        registers = [
+            "name:rax;bitsize:64;offset:0;encoding:uint;format:hex;set:General Purpose Registers;ehframe:0;dwarf:0;",
+            "name:rbx;bitsize:64;offset:8;encoding:uint;format:hex;set:General Purpose Registers;ehframe:3;dwarf:3;",
+            "name:rcx;bitsize:64;offset:16;encoding:uint;format:hex;set:General Purpose Registers;ehframe:2;dwarf:2;generic:arg4;",
+            "name:rdx;bitsize:64;offset:24;encoding:uint;format:hex;set:General Purpose Registers;ehframe:1;dwarf:1;generic:arg3;",
+            "name:rdi;bitsize:64;offset:32;encoding:uint;format:hex;set:General Purpose Registers;ehframe:5;dwarf:5;generic:arg1;",
+            "name:rsi;bitsize:64;offset:40;encoding:uint;format:hex;set:General Purpose Registers;ehframe:4;dwarf:4;generic:arg2;",
+            "name:rbp;bitsize:64;offset:48;encoding:uint;format:hex;set:General Purpose Registers;ehframe:6;dwarf:6;generic:fp;",
+            "name:rsp;bitsize:64;offset:56;encoding:uint;format:hex;set:General Purpose Registers;ehframe:7;dwarf:7;generic:sp;",
+        ]
+
+        def qRegisterInfo(self, num):
+            try:
+                return self.registers[num]
+            except IndexError:
+                return "E45"
+
         def readRegisters(self):
-            return '0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000'
+            return len(self.registers) * 16 * '0'
+
+        def readRegister(self, register):
+            return "0000000000000000"
 
     def test_connect(self):
         """Test connecting to a remote gdb server"""
@@ -88,6 +108,7 @@
         """Test reading registers using 'p' packets"""
         self.dbg.HandleCommand(
                 "settings set plugin.process.gdb-remote.use-g-packet-for-reading false")
+        self.server.responder = self.gPacketResponder()
         target = self.createTarget("a.yaml")
         process = self.connect(target)
 
@@ -128,11 +149,11 @@
 
     def read_registers(self, process):
         self.for_each_gpr(
-                process, lambda r: self.assertEquals("0x00000000", r.GetValue()))
+                process, lambda r: self.assertEquals("0x0000000000000000", r.GetValue()))
 
     def write_registers(self, process):
         self.for_each_gpr(
-                process, lambda r: r.SetValueFromCString("0x00000000"))
+                process, lambda r: r.SetValueFromCString("0x0000000000000000"))
 
     def for_each_gpr(self, process, operation):
         registers = process.GetThreadAtIndex(0).GetFrameAtIndex(0).GetRegisters()
diff --git a/lldb/test/API/functionalities/gdb_remote_client/a.yaml b/lldb/test/API/functionalities/gdb_remote_client/a.yaml
--- a/lldb/test/API/functionalities/gdb_remote_client/a.yaml
+++ b/lldb/test/API/functionalities/gdb_remote_client/a.yaml
@@ -1,9 +1,9 @@
-!ELF
+--- !ELF
 FileHeader:
-  Class:           ELFCLASS32
+  Class:           ELFCLASS64
   Data:            ELFDATA2LSB
   Type:            ET_EXEC
-  Machine:         EM_ARM
+  Machine:         EM_X86_64
 Sections:
   - Name:            .text
     Type:            SHT_PROGBITS
diff --git a/lldb/test/API/functionalities/gdb_remote_client/gdbclientutils.py b/lldb/test/API/functionalities/gdb_remote_client/gdbclientutils.py
--- a/lldb/test/API/functionalities/gdb_remote_client/gdbclientutils.py
+++ b/lldb/test/API/functionalities/gdb_remote_client/gdbclientutils.py
@@ -200,6 +200,9 @@
             return self.QEnvironment(packet)
         if packet.startswith("QEnvironmentHexEncoded:"):
             return self.QEnvironmentHexEncoded(packet)
+        if packet.startswith("qRegisterInfo"):
+            regnum = int(packet[len("qRegisterInfo"):], 16)
+            return self.qRegisterInfo(regnum)
 
         return self.other(packet)
 
@@ -325,6 +328,9 @@
     def QEnvironmentHexEncoded(self, packet):
         return "OK"
 
+    def qRegisterInfo(self, num):
+        return ""
+
     """
     Raised when we receive a packet for which there is no default action.
     Override the responder class to implement behavior suitable for the test at