Merge pull request #9020 from Tilka/usb

IOS/USB: fix potential race condition

Source/Core/Core/IOS/USB/Host.cpp

@@ -31,7 +31,10 @@ USBHost::USBHost(Kernel& ios, const std::string& device_name) : Device(ios, devi
 {
 }
 
-USBHost::~USBHost() = default;
+USBHost::~USBHost()
+{
+  StopThreads();
+}
 
 IPCCommandResult USBHost::Open(const OpenRequest& request)
 {
@@ -179,9 +182,8 @@ void USBHost::StartThreads()
   if (Core::WantsDeterminism())
     return;
 
-  if (!m_scan_thread_running.IsSet())
+  if (m_scan_thread_running.TestAndSet())
   {
-    m_scan_thread_running.Set();
     m_scan_thread = std::thread([this] {
       Common::SetCurrentThreadName("USB Scan Thread");
       while (m_scan_thread_running.IsSet())

Source/Core/Core/IOS/USB/Host.h

@@ -53,13 +53,14 @@ protected:
   virtual void OnDeviceChange(ChangeEvent event, std::shared_ptr<USB::Device> changed_device);
   virtual void OnDeviceChangeEnd();
   virtual bool ShouldAddDevice(const USB::Device& device) const;
-  void StartThreads();
-  void StopThreads();
 
   IPCCommandResult HandleTransfer(std::shared_ptr<USB::Device> device, u32 request,
                                   std::function<s32()> submit) const;
 
 private:
+  void StartThreads();
+  void StopThreads();
+
   bool AddDevice(std::unique_ptr<USB::Device> device);
   bool UpdateDevices(bool always_add_hooks = false);
 

Source/Core/Core/IOS/USB/OH0/OH0.cpp

@@ -26,11 +26,6 @@ OH0::OH0(Kernel& ios, const std::string& device_name) : USBHost(ios, device_name
 {
 }
 
-OH0::~OH0()
-{
-  StopThreads();
-}
-
 IPCCommandResult OH0::Open(const OpenRequest& request)
 {
   if (HasFeature(m_ios.GetVersion(), Feature::NewUSB))

Source/Core/Core/IOS/USB/OH0/OH0.h

@@ -37,7 +37,6 @@ class OH0 final : public USBHost
 {
 public:
   OH0(Kernel& ios, const std::string& device_name);
-  ~OH0() override;
 
   IPCCommandResult Open(const OpenRequest& request) override;
   IPCCommandResult IOCtl(const IOCtlRequest& request) override;

Source/Core/Core/IOS/USB/USBV5.cpp

@@ -86,11 +86,6 @@ struct DeviceEntry
 #pragma pack(pop)
 }  // namespace
 
-USBV5ResourceManager::~USBV5ResourceManager()
-{
-  StopThreads();
-}
-
 void USBV5ResourceManager::DoState(PointerWrap& p)
 {
   p.Do(m_devicechange_first_call);

Source/Core/Core/IOS/USB/USBV5.h

@@ -69,7 +69,6 @@ class USBV5ResourceManager : public USBHost
 {
 public:
   using USBHost::USBHost;
-  ~USBV5ResourceManager() override;
 
   IPCCommandResult IOCtl(const IOCtlRequest& request) override = 0;
   IPCCommandResult IOCtlV(const IOCtlVRequest& request) override = 0;

Source/Core/Core/IOS/USB/USB_HID/HIDv4.cpp

@@ -26,11 +26,6 @@ USB_HIDv4::USB_HIDv4(Kernel& ios, const std::string& device_name) : USBHost(ios,
 {
 }
 
-USB_HIDv4::~USB_HIDv4()
-{
-  StopThreads();
-}
-
 IPCCommandResult USB_HIDv4::IOCtl(const IOCtlRequest& request)
 {
   request.Log(GetDeviceName(), Common::Log::IOS_USB);

Source/Core/Core/IOS/USB/USB_HID/HIDv4.h

@@ -22,7 +22,6 @@ class USB_HIDv4 final : public USBHost
 {
 public:
   USB_HIDv4(Kernel& ios, const std::string& device_name);
-  ~USB_HIDv4() override;
 
   IPCCommandResult IOCtl(const IOCtlRequest& request) override;