diff --git a/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/TestPlatformClient.py b/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/TestPlatformClient.py
new file mode 100644
--- /dev/null
+++ b/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/TestPlatformClient.py
@@ -0,0 +1,27 @@
+import lldb
+import binascii
+import os
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test.decorators import *
+from gdbclientutils import *
+
+
+class TestPlatformClient(GDBRemoteTestBase):
+
+    def test_process_list_with_all_users(self):
+        """Test connecting to a remote linux platform"""
+
+        self.runCmd("log enable gdb-remote all")
+        self.runCmd("platform select remote-linux")
+
+        try:
+            self.runCmd("platform connect connect://localhost:%d" %
+                        self.server.port)
+            self.assertTrue(self.dbg.GetSelectedPlatform().IsConnected())
+            self.expect("platform process list -x",
+                        substrs=["1 matching process was found", "test_process"])
+            self.expect("platform process list",
+                        error=True,
+                        substrs=["error: no processes were found on the \"remote-linux\" platform"])
+        finally:
+            self.dbg.GetSelectedPlatform().DisconnectRemote()
diff --git a/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/gdbclientutils.py b/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/gdbclientutils.py
--- a/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/gdbclientutils.py
+++ b/lldb/packages/Python/lldbsuite/test/functionalities/gdb_remote_client/gdbclientutils.py
@@ -160,9 +160,37 @@
             return self.QListThreadsInStopReply()
         if packet.startswith("qMemoryRegionInfo:"):
             return self.qMemoryRegionInfo()
+        if packet == "qQueryGDBServer":
+            return self.qQueryGDBServer()
+        if packet == "qHostInfo":
+            return self.qHostInfo()
+        if packet == "qGetWorkingDir":
+            return self.qGetWorkingDir()
+        if packet == "qsProcessInfo":
+            return self.qsProcessInfo()
+        if packet.startswith("qfProcessInfo"):
+            return self.qfProcessInfo(packet)
 
         return self.other(packet)
 
+    def qsProcessInfo(self):
+        return "E04"
+
+    def qfProcessInfo(self, packet):
+        if "all_users:1" in packet:
+            return "pid:10;ppid:1;uid:1;gid:1;euid:1;egid:1;name:" + binascii.hexlify("/a/test_process") + ";"
+        else:
+            return "E04"
+
+    def qGetWorkingDir(self):
+        return "2f"
+
+    def qHostInfo(self):
+        return "ptrsize:8;endian:little;"
+
+    def qQueryGDBServer(self):
+        return "E04"
+
     def interrupt(self):
         raise self.UnexpectedPacketException()
 
@@ -171,7 +199,7 @@
 
     def vCont(self, packet):
         raise self.UnexpectedPacketException()
-    
+
     def readRegisters(self):
         return "00000000" * self.registerCount
 
@@ -425,7 +453,6 @@
     class InvalidPacketException(Exception):
         pass
 
-
 class GDBRemoteTestBase(TestBase):
     """
     Base class for GDB client tests.
diff --git a/lldb/source/Commands/CommandObjectPlatform.cpp b/lldb/source/Commands/CommandObjectPlatform.cpp
--- a/lldb/source/Commands/CommandObjectPlatform.cpp
+++ b/lldb/source/Commands/CommandObjectPlatform.cpp
@@ -1264,6 +1264,10 @@
         verbose = true;
         break;
 
+      case 'x':
+        match_info.SetMatchAllUsers(true);
+        break;
+
       default:
         llvm_unreachable("Unimplemented option");
       }
diff --git a/lldb/source/Commands/Options.td b/lldb/source/Commands/Options.td
--- a/lldb/source/Commands/Options.td
+++ b/lldb/source/Commands/Options.td
@@ -591,6 +591,9 @@
   def platform_process_list_show_args : Option<"show-args", "A">,
     GroupRange<1, 6>,
     Desc<"Show process arguments instead of the process executable basename.">;
+  def platform_process_list_all_users: Option<"all-users", "x">,
+    GroupRange<1,6>,
+    Desc<"Show processes matching all user IDs.">;
   def platform_process_list_verbose : Option<"verbose", "v">, GroupRange<1, 6>,
     Desc<"Enable verbose output.">;
 }
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
@@ -2176,8 +2176,7 @@
       if (match_info.GetProcessInfo().EffectiveGroupIDIsValid())
         packet.Printf("egid:%u;",
                       match_info.GetProcessInfo().GetEffectiveGroupID());
-      if (match_info.GetProcessInfo().EffectiveGroupIDIsValid())
-        packet.Printf("all_users:%u;", match_info.GetMatchAllUsers() ? 1 : 0);
+      packet.Printf("all_users:%u;", match_info.GetMatchAllUsers() ? 1 : 0);
       if (match_info.GetProcessInfo().GetArchitecture().IsValid()) {
         const ArchSpec &match_arch =
             match_info.GetProcessInfo().GetArchitecture();