axeld + bonefish:

Certain interrupts don't disable interrupts. We were calling 
x86_{push,pop}_iframe() without specifically disabling them, thus causing 
a race condition with could cause the iframe stack to be invalid. This 
could cause all kinds of problems.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@21784 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/system/kernel/arch/x86/arch_int.c

@@ -355,10 +355,13 @@ i386_handle_trap(struct iframe frame)
 {
 	struct thread *thread = thread_get_current_thread();
 	int ret = B_HANDLED_INTERRUPT;
+	cpu_status state;
 
 	// all exceptions besides 3 (breakpoint), and 99 (syscall) enter this
 	// function with interrupts disabled
 
+	state = disable_interrupts();
+
 	if (thread)
 		x86_push_iframe(&thread->arch_info.iframes, &frame);
 	else
@@ -369,6 +372,8 @@ i386_handle_trap(struct iframe frame)
 		thread_at_kernel_entry();
 	}
 
+	restore_interrupts(state);
+
 //	if(frame.vector != 0x20)
 //		dprintf("i386_handle_trap: vector 0x%x, ip 0x%x, cpu %d\n", frame.vector, frame.eip, smp_get_current_cpu());
 
@@ -457,7 +462,6 @@ i386_handle_trap(struct iframe frame)
 
 			if (kernelDebugger) {
 				// if this thread has a fault handler, we're allowed to be here
-				struct thread *thread = thread_get_current_thread();
 				if (thread && thread->fault_handler != NULL) {
 					frame.eip = thread->fault_handler;
 					break;
@@ -589,6 +593,8 @@ i386_handle_trap(struct iframe frame)
 
 //	dprintf("0x%x cpu %d!\n", thread_get_current_thread_id(), smp_get_current_cpu());
 
+	disable_interrupts();
+
 	if (thread)
 		x86_pop_iframe(&thread->arch_info.iframes);
 	else