From cd8b436566a26a34758632b567e5c205eb327f74 Mon Sep 17 00:00:00 2001
From: Alexander Boettcher <alexander.boettcher@genode-labs.com>
Date: Tue, 10 Nov 2020 14:09:58 +0100
Subject: [PATCH] usb_hid: avoid destruction of used signal handler

Fixes #3945
---
 repos/dde_linux/src/drivers/usb_hid/driver.h |  5 +++++
 repos/dde_linux/src/drivers/usb_hid/main.cc  | 11 ++++++++++-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/repos/dde_linux/src/drivers/usb_hid/driver.h b/repos/dde_linux/src/drivers/usb_hid/driver.h
index e463e5bbac..a3acc44d26 100644
--- a/repos/dde_linux/src/drivers/usb_hid/driver.h
+++ b/repos/dde_linux/src/drivers/usb_hid/driver.h
@@ -33,11 +33,14 @@ struct Driver
 	{
 		Lx::Task                     task;
 		Genode::Signal_handler<Task> handler;
+		bool                         handling_signal { false };
 	
 		void handle_signal()
 		{
 			task.unblock();
+			handling_signal = true;
 			Lx::scheduler().schedule();
+			handling_signal = false;
 		}
 	
 		template <typename... ARGS>
@@ -56,6 +59,7 @@ struct Driver
 		Genode::Allocator_avl         &alloc;
 		Task                           state_task;
 		Task                           urb_task;
+
 		Usb::Connection                usb { env, &alloc, label.string(),
 		                                     512 * 1024, state_task.handler };
 		usb_device                   * udev = nullptr;
@@ -70,6 +74,7 @@ struct Driver
 		void unregister_device();
 		void probe_interface(usb_interface *, usb_device_id *);
 		void remove_interface(usb_interface *);
+		bool deinit();
 	};
 
 	struct Devices : Genode::List<Device::Le>
diff --git a/repos/dde_linux/src/drivers/usb_hid/main.cc b/repos/dde_linux/src/drivers/usb_hid/main.cc
index 32d062d860..35189b7639 100644
--- a/repos/dde_linux/src/drivers/usb_hid/main.cc
+++ b/repos/dde_linux/src/drivers/usb_hid/main.cc
@@ -142,7 +142,14 @@ Driver::Device::Device(Driver & driver, Label label)
 Driver::Device::~Device()
 {
 	driver.devices.remove(&le);
+}
+
+
+bool Driver::Device::deinit()
+{
 	if (udev) unregister_device();
+
+	return !udev && !state_task.handling_signal && !urb_task.handling_signal;
 }
 
 
@@ -228,7 +235,9 @@ void Driver::scan_report()
 	};
 
 	devices.for_each([&] (Device & d) {
-		if (!d.updated) destroy(heap, &d); });
+		if (!d.updated && d.deinit())
+			destroy(heap, &d);
+	});
 }