diff --git a/stratosphere/loader/source/ldr_ecs.cpp b/stratosphere/loader/source/ldr_ecs.cpp
index 91da78849..a49a3ebd7 100644
--- a/stratosphere/loader/source/ldr_ecs.cpp
+++ b/stratosphere/loader/source/ldr_ecs.cpp
@@ -28,15 +28,41 @@ namespace ams::ldr::ecs {
             NON_COPYABLE(ExternalContentSource);
             NON_MOVEABLE(ExternalContentSource);
             private:
+                bool has_mounted = false;
                 char device_name[DeviceNameSizeMax];
+                os::ManagedHandle client;
+
+                Result Mount() {
+                    /* Create service. */
+                    Service srv;
+                    serviceCreate(&srv, client.Move());
+                    FsFileSystem fs = { srv };
+                    auto fs_guard = SCOPE_GUARD { fsFsClose(&fs); };
+
+                    /* Try to mount. */
+                    R_UNLESS(fsdevMountDevice(device_name, fs) >= 0, fs::ResultMountNameAlreadyExists());
+                    fs_guard.Cancel();
+
+                    this->has_mounted = true;
+                    return ResultSuccess();
+                }
             public:
-                ExternalContentSource(const char *dn) {
+                ExternalContentSource(const char *dn, os::ManagedHandle client) : client(std::move(client)) {
                     std::strncpy(this->device_name, dn, sizeof(this->device_name));
                     this->device_name[sizeof(this->device_name) - 1] = '\0';
                 }
 
+                Result EnsureMounted() {
+                    if (!this->has_mounted) {
+                        return Mount();
+                    }
+                    return ResultSuccess();
+                }
+
                 ~ExternalContentSource() {
-                    fsdevUnmountDevice(this->device_name);
+                    if (this->has_mounted) {
+                        fsdevUnmountDevice(this->device_name);
+                    }
                 }
 
                 const char *GetDeviceName() const {
@@ -54,6 +80,10 @@ namespace ams::ldr::ecs {
         if (it == g_map.end()) {
             return nullptr;
         }
+        if (R_FAILED(it->second.EnsureMounted())) {
+            g_map.erase(it);
+            return nullptr;
+        }
         return it->second.GetDeviceName();
     }
 
@@ -72,18 +102,13 @@ namespace ams::ldr::ecs {
         os::ManagedHandle server, client;
         R_TRY(svcCreateSession(server.GetPointer(), client.GetPointer(), 0, 0));
 
-        /* Create service. */
-        Service srv;
-        serviceCreate(&srv, client.Move());
-        FsFileSystem fs = { srv };
-        auto fs_guard = SCOPE_GUARD { fsFsClose(&fs); };
-
-        /* Try to mount. */
-        R_UNLESS(fsdevMountDevice(device_name, fs) >= 0, fs::ResultMountNameAlreadyExists());
-        fs_guard.Cancel();
+        /* Do not create service yet. */
+        /* Defer until we've handed the server side back so we don't deadlock on querying pointer buffer size. */
 
         /* Add to map. */
-        g_map.emplace(static_cast<u64>(program_id), device_name);
+        g_map.emplace(std::piecewise_construct,
+                      std::make_tuple(static_cast<u64>(program_id)),
+                      std::make_tuple(device_name, std::move(client)));
         *out = server.Move();
         return ResultSuccess();
     }