From 7fcf9053b910cbd1d41fa96d5942120de3e80c04 Mon Sep 17 00:00:00 2001
From: Sebastian Sumpf <sebastian.sumpf@genode-labs.com>
Date: Thu, 20 May 2021 18:57:58 +0200
Subject: [PATCH] usb_hid: perform device destruction on unplug signal only

- Do not perform desctruction on report updatea in EP because
  'unregister_device' may block on Led state 'update' (synchronous
  control message) leading to the driver being stuck because no more
  signals are received
- Check if device is present in 'submit_urb' calls

fixes #4166
---
 repos/dde_linux/src/drivers/usb_hid/main.cc    |  7 +++----
 repos/dde_linux/src/include/lx_emul/impl/usb.h | 10 ++++++++++
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/repos/dde_linux/src/drivers/usb_hid/main.cc b/repos/dde_linux/src/drivers/usb_hid/main.cc
index 498f351c57..a0670670d0 100644
--- a/repos/dde_linux/src/drivers/usb_hid/main.cc
+++ b/repos/dde_linux/src/drivers/usb_hid/main.cc
@@ -160,8 +160,6 @@ Driver::Device::~Device()
 
 bool Driver::Device::deinit()
 {
-	if (udev) unregister_device();
-
 	return !udev && !state_task.handling_signal && !urb_task.handling_signal;
 }
 
@@ -224,8 +222,9 @@ void Driver::scan_report()
 	if (!report_rom.constructed()) {
 		report_rom.construct(env, "report");
 		report_rom->sigh(main_task->handler);
-	} else
-		report_rom->update();
+	}
+
+	report_rom->update();
 
 	devices.for_each([&] (Device & d) { d.updated = false; });
 
diff --git a/repos/dde_linux/src/include/lx_emul/impl/usb.h b/repos/dde_linux/src/include/lx_emul/impl/usb.h
index b6f4c2e78d..7183651912 100644
--- a/repos/dde_linux/src/include/lx_emul/impl/usb.h
+++ b/repos/dde_linux/src/include/lx_emul/impl/usb.h
@@ -44,6 +44,13 @@ int usb_control_msg(struct usb_device *dev, unsigned int pipe,
 	usb_fill_control_urb(u, dev, pipe, (unsigned char *)dr, data,
 	                     size, nullptr, nullptr);
 
+	if (!dev->bus || !dev->bus->controller) {
+		kfree(scu);
+		usb_free_urb(u);
+		kfree(dr);
+		return -ENODEV;
+	}
+
 	Genode::construct_at<Sync_ctrl_urb>(scu, *(Usb::Connection*)(dev->bus->controller), *u);
 
 	scu->send(timeout);
@@ -76,6 +83,9 @@ struct urb *usb_alloc_urb(int iso_packets, gfp_t mem_flags)
 
 int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
 {
+	if (!urb->dev->bus || !urb->dev->bus->controller)
+		return -ENODEV;
+
 	Urb * u = (Urb *)kzalloc(sizeof(Urb), mem_flags);
 	if (!u)
 		return 1;