From b79525156434314eee292326c58eabd0fa8e68df Mon Sep 17 00:00:00 2001
From: beveloper <beveloper@nowhere.fake>
Date: Sun, 17 Nov 2002 00:52:43 +0000
Subject: [PATCH] This code seems to have some issues. Please check.

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@1971 a95241bf-73f2-0310-859d-f6bbb57e9c96
---
 src/kernel/core/int.c       | 16 ++++++++--------
 src/kernel/core/scheduler.c |  4 ++--
 src/kernel/core/signal.c    |  5 +++--
 3 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/src/kernel/core/int.c b/src/kernel/core/int.c
index c62b322def..db01fca5e0 100644
--- a/src/kernel/core/int.c
+++ b/src/kernel/core/int.c
@@ -95,17 +95,17 @@ install_interrupt_handler(long vector, interrupt_handler handler, void *data)
 	io->func = handler;
 	io->data = data;
 
-	/* Make sure our list is init'd or bad things will happen */
-	if (io_vectors[vector].handler_list.next == NULL) {
-		io_vectors[vector].handler_list.next = &io_vectors[vector].handler_list;
-		io_vectors[vector].handler_list.prev = &io_vectors[vector].handler_list;
-	}
-
 	/* Disable the interrupts, get the spinlock for this irq only
 	 * and then insert the handler */
 	state = disable_interrupts();
 	acquire_spinlock(&io_vectors[vector].vector_lock);
 
+	/* Make sure our list is init'd or bad things will happen */ //XXX this should not be needed
+	if (io_vectors[vector].handler_list.next == NULL) {
+		io_vectors[vector].handler_list.next = &io_vectors[vector].handler_list;
+		io_vectors[vector].handler_list.prev = &io_vectors[vector].handler_list;
+	}
+
 	insque(io, &io_vectors[vector].handler_list);
 
 	release_spinlock(&io_vectors[vector].vector_lock);
@@ -165,7 +165,7 @@ remove_interrupt_handler(long vector, interrupt_handler handler, void *data)
 		/* we have to match both function and data */
 		if (io->func == handler && io->data == data) {
 			remque(io);
-			free(io);
+			free(io); // XXX free() should not be called inside a spinlock or with disabled interrupts
 			rv = 0;
 			break;
 		}
@@ -237,7 +237,7 @@ int_io_interrupt_handler(int vector)
 		 *       right.
 		 */
 		for (io = io_vectors[vector].handler_list.next; 
-		     io != &io_vectors[vector].handler_list;
+		     io != &io_vectors[vector].handler_list; //XXX DOES this work for 1 entry?
 		     io = io->next) {
 			if ((ret = io->func(io->data)) != B_UNHANDLED_INTERRUPT)
 				break;
diff --git a/src/kernel/core/scheduler.c b/src/kernel/core/scheduler.c
index 998f173cab..0e0421bb21 100644
--- a/src/kernel/core/scheduler.c
+++ b/src/kernel/core/scheduler.c
@@ -48,7 +48,7 @@ dump_run_q(int argc, char **argv)
 
 
 void
-thread_enqueue_run_q(struct thread *t)
+thread_enqueue_run_q(struct thread *t) //XXX no locks? is this save?
 {
 	struct thread *curr, *prev;
 	
@@ -93,7 +93,7 @@ thread_set_priority(thread_id id, int32 priority)
 	if (t->id == id) {
 		// it's ourself, so we know we aren't in the run queue, and we can manipulate
 		// our structure directly
-		retval = t->priority;
+		retval = t->priority; //XXX is this really save? can't we get preempted right here?
 		t->priority = priority;
 	} else {
 		int state = disable_interrupts();
diff --git a/src/kernel/core/signal.c b/src/kernel/core/signal.c
index 2eb1feab81..97bf7c8956 100644
--- a/src/kernel/core/signal.c
+++ b/src/kernel/core/signal.c
@@ -169,7 +169,7 @@ send_signal_etc(pid_t tid, uint sig, uint32 flags)
 	}
 	
 	if (!(flags & B_DO_NOT_RESCHEDULE))
-		resched();
+		resched(); //XXX really here, while interrupts are disabled?
 	
 	RELEASE_THREAD_LOCK();
 	restore_interrupts(state);
@@ -264,7 +264,8 @@ sys_set_alarm(bigtime_t time, uint32 mode)
 	int state;
 	bigtime_t rv = 0;
 	
-	state = disable_interrupts();
+	state = disable_interrupts(); //XXX really here? and what about a spinlock?
+
 	
 	if (t->alarm.period)
 		rv = (bigtime_t)t->alarm.entry.key - system_time();