dde_linux: preserve Io_signal_handler for IRQs

Do not construct/destruct signal handlers for interrupts dynamically,
but only the Irq session to prevent a deadlock.

Fix #4272

repos/dde_linux/src/include/lx_kit/device.h

@@ -59,39 +59,19 @@ class Lx_kit::Device : List<Device>::Element
 			: idx{idx}, addr(addr), size(size) {}
 		};
 
-		struct Irq_handler
-		{
-			private:
-
-				Irq_handler(Irq_handler const &);
-				Irq_handler &operator = (Irq_handler const &);
-
-				Platform::Device::Irq          _irq;
-				Io_signal_handler<Irq_handler> _handler;
-				unsigned                       _number;
-
-				void _handle();
-
-			public:
-
-				Irq_handler(Platform::Device & dev,
-				            Platform::Device::Irq::Index idx,
-				            unsigned number);
-
-				void ack() { _irq.ack(); }
-		};
-
 		struct Irq : List<Irq>::Element
 		{
 			using Index = Platform::Device::Irq::Index;
 
 			Index                  idx;
 			unsigned               number;
+			Io_signal_handler<Irq> handler;
 
-			Constructible<Irq_handler> handler {};
+			Constructible<Platform::Device::Irq> session {};
 
-			Irq(unsigned idx, unsigned number)
+			Irq(Entrypoint & ep, unsigned idx, unsigned number);
-			: idx{idx}, number(number) {}
+
+			void handle();
 		};
 
 		struct Clock : List<Clock>::Element
@@ -104,7 +84,8 @@ class Lx_kit::Device : List<Device>::Element
 			: idx(idx), name(name), lx_clock{0} {}
 		};
 
-		Device(Platform::Connection & plat,
+		Device(Entrypoint           & ep,
+		       Platform::Connection & plat,
 		       Xml_node             & xml,
 		       Heap                 & heap);
 
@@ -156,7 +137,9 @@ class Lx_kit::Device_list : List<Device>
 		void for_each(FN const & fn) {
 			for (Device * d = first(); d; d = d->next()) fn(*d); }
 
-		Device_list(Heap & heap, Platform::Connection & platform);
+		Device_list(Entrypoint           & ep,
+		            Heap                 & heap,
+		            Platform::Connection & platform);
 };
 
 #endif /* _LX_KIT__DEVICE_H_ */

repos/dde_linux/src/include/lx_kit/env.h

@@ -48,7 +48,7 @@ struct Lx_kit::Env
 	Mem_allocator        memory          { env, heap, platform, CACHED   };
 	Mem_allocator        uncached_memory { env, heap, platform, UNCACHED };
 	Scheduler            scheduler       { };
-	Device_list          devices         { heap, platform   };
+	Device_list          devices         { env.ep(), heap, platform };
 	Lx_kit::Timeout      timeout         { timer, scheduler };
 	unsigned int         last_irq        { 0 };
 

repos/dde_linux/src/lib/lx_kit/device.cc

@@ -27,29 +27,23 @@ bool Device::Io_mem::match(addr_t addr, size_t size)
 }
 
 
-/*************************
+/****************
- ** Device::Irq_handler **
+ ** Device::Irq**
- *************************/
+ ****************/
 
-void Device::Irq_handler::_handle()
+void Device::Irq::handle()
 {
-	env().last_irq = _number;
+	env().last_irq = number;
 	env().scheduler.unblock_irq_handler();
 	env().scheduler.schedule();
 }
 
 
-Device::Irq_handler::Irq_handler(Platform::Device & dev,
+Device::Irq::Irq(Entrypoint & ep, unsigned idx, unsigned number)
-                                 Platform::Device::Irq::Index idx,
-                                 unsigned number)
 :
-	_irq(dev, idx),
+	idx{idx},
-	_handler(Lx_kit::env().env.ep(), *this, &Irq_handler::_handle),
+	number(number),
-	_number(number)
+	handler(ep, *this, &Irq::handle) { }
-{
-	_irq.sigh_omit_initial_signal(_handler);
-	_irq.ack();
-}
 
 
 /************
@@ -132,13 +126,15 @@ bool Device::irq_unmask(unsigned number)
 		if (irq.number != number)
 			return;
 
+		ret = true;
 		enable();
 
-		if (irq.handler.constructed())
+		if (irq.session.constructed())
 			return;
 
-		irq.handler.construct(*_pdev, irq.idx, number);
+		irq.session.construct(*_pdev, irq.idx);
-		ret = true;
+		irq.session->sigh_omit_initial_signal(irq.handler);
+		irq.session->ack();
 	});
 
 	return ret;
@@ -153,7 +149,7 @@ void Device::irq_mask(unsigned number)
 	_for_each_irq([&] (Irq & irq) {
 		if (irq.number != number)
 			return;
-		irq.handler.destruct();
+		irq.session.destruct();
 	});
 
 }
@@ -165,9 +161,9 @@ void Device::irq_ack(unsigned number)
 		return;
 
 	_for_each_irq([&] (Irq & irq) {
-		if (irq.number != number)
+		if (irq.number != number || !irq.session.constructed())
 			return;
-		irq.handler->ack();
+		irq.session->ack();
 	});
 }
 
@@ -196,7 +192,8 @@ void Device::enable()
 }
 
 
-Device::Device(Platform::Connection & plat,
+Device::Device(Entrypoint           & ep,
+               Platform::Connection & plat,
                Xml_node             & xml,
                Heap                 & heap)
 :
@@ -213,7 +210,7 @@ Device::Device(Platform::Connection & plat,
 
 	i = 0;
 	xml.for_each_sub_node("irq", [&] (Xml_node node) {
-		_irqs.insert(new (heap) Irq(i++, node.attribute_value("number", 0U)));
+		_irqs.insert(new (heap) Irq(ep, i++, node.attribute_value("number", 0U)));
 	});
 
 	i = 0;
@@ -228,13 +225,15 @@ Device::Device(Platform::Connection & plat,
  ** Device_list **
  *****************/
 
-Device_list::Device_list(Heap & heap, Platform::Connection & platform)
+Device_list::Device_list(Entrypoint           & ep,
+                         Heap                 & heap,
+                         Platform::Connection & platform)
 :
 	_platform(platform)
 {
 	_platform.with_xml([&] (Xml_node & xml) {
 		xml.for_each_sub_node("device", [&] (Xml_node node) {
-			insert(new (heap) Device(_platform, node, heap));
+			insert(new (heap) Device(ep, _platform, node, heap));
 		});
 	});
 }