Kernel: VirtualTTY now resets ansi state before printing anything

Scheduler keeps crashing all the time when running on multiple cores.
This patch disabled the load balancer, which seems to get rid of most
scheduler crashes.

kernel/kernel/Scheduler.cpp

@@ -8,6 +8,7 @@
 
 #define DEBUG_SCHEDULER 0
 #define SCHEDULER_ASSERT 1
+#define SCHEDULER_LOAD_BALANCE 0
 
 #if SCHEDULER_ASSERT == 0
 #undef ASSERT
@@ -295,8 +296,9 @@ namespace Kernel
 	{
 		ASSERT(Processor::get_interrupt_state() == InterruptState::Disabled);
 
-		if (Processor::is_smp_enabled())
+		if constexpr(SCHEDULER_LOAD_BALANCE)
-			do_load_balancing();
+			if (Processor::is_smp_enabled())
+				do_load_balancing();
 
 		{
 			const uint64_t current_ns = SystemTimer::get().ns_since_boot();
@@ -386,6 +388,7 @@ namespace Kernel
 		return least_loaded_id;
 	}
 
+#if SCHEDULER_LOAD_BALANCE
 	void Scheduler::do_load_balancing()
 	{
 		ASSERT(Processor::get_interrupt_state() == InterruptState::Disabled);
@@ -563,6 +566,7 @@ namespace Kernel
 
 		m_last_load_balance_ns += s_load_balance_interval_ns;
 	}
+#endif
 
 	BAN::ErrorOr<void> Scheduler::add_thread(Thread* thread)
 	{

kernel/kernel/Terminal/VirtualTTY.cpp

@@ -221,8 +221,9 @@ namespace Kernel
 					for (uint32_t row = 0; row < m_height; row++)
 						for (uint32_t col = 0; col < m_width; col++)
 							putchar_at(' ', col, row);
+					return reset_ansi();
 				}
-				else if (m_ansi_state.nums[0] == 1)
+				if (m_ansi_state.nums[0] == 1)
 				{
 					// Clear from cursor to the beginning of screen
 					for (uint32_t row = 0; row < m_row; row++)
@@ -230,29 +231,27 @@ namespace Kernel
 							putchar_at(' ', col, row);
 					for (uint32_t i = 0; i <= m_column; i++)
 						putchar_at(' ', i, m_row);
+					return reset_ansi();
 				}
-				else if (m_ansi_state.nums[0] == 2 || m_ansi_state.nums[0] == 3)
+				if (m_ansi_state.nums[0] == 2 || m_ansi_state.nums[0] == 3)
 				{
-					// Clean entire screen
+					// FIXME: if num == 3 clear scrollback buffer
 					clear();
+					return reset_ansi();
 				}
-				else
+				reset_ansi();
-				{
+				dprintln("Unsupported ANSI CSI character J");
-					dprintln("Unsupported ANSI CSI character J");
+				return;
-				}
-
-				if (m_ansi_state.nums[0] == 3)
-				{
-					// FIXME: Clear scroll backbuffer if/when added
-				}
-				return reset_ansi();
 			case 'K': // Erase in Line
 				if (m_ansi_state.nums[0] == -1 || m_ansi_state.nums[0] == 0)
+				{
 					for (uint32_t i = m_column; i < m_width; i++)
 						putchar_at(' ', i, m_row);
-				else
+					return reset_ansi();
-					dprintln("Unsupported ANSI CSI character K");
+				}
-				return reset_ansi();
+				reset_ansi();
+				dprintln("Unsupported ANSI CSI character K");
+				return;
 			case 'L': // Insert Line
 				if (m_ansi_state.nums[0] == -1)
 					m_ansi_state.nums[0] = 1;
@@ -286,14 +285,17 @@ namespace Kernel
 						putchar_at(' ', x, m_height - y_off - 1);
 				return reset_ansi();
 			case 'S': // Scroll Up
+				reset_ansi();
 				dprintln("Unsupported ANSI CSI character S");
-				return reset_ansi();
+				return;
 			case 'T': // Scroll Down
+				reset_ansi();
 				dprintln("Unsupported ANSI CSI character T");
-				return reset_ansi();
+				return;
 			case 'f': // Horizontal Vertical Position
+				reset_ansi();
 				dprintln("Unsupported ANSI CSI character f");
-				return reset_ansi();
+				return;
 			case 'm':
 				handle_ansi_csi_color();
 				return reset_ansi();
@@ -331,25 +333,28 @@ namespace Kernel
 				m_row = BAN::Math::clamp<uint32_t>(m_ansi_state.nums[0], 1, m_height) - 1;
 				return reset_ansi();
 			case '?':
-				if (m_ansi_state.index != 0 || m_ansi_state.nums[0] != -1)
+				if (m_ansi_state.index == 0 || m_ansi_state.nums[0] == -1)
 				{
-					dprintln("invalid ANSI CSI ?");
+					m_ansi_state.question = true;
 					return reset_ansi();
 				}
-				m_ansi_state.question = true;
+				reset_ansi();
+				dprintln("invalid ANSI CSI ?");
 				return;
 			case 'h':
 			case 'l':
-				if (!m_ansi_state.question || m_ansi_state.nums[0] != 25)
+				if (m_ansi_state.question && m_ansi_state.nums[0] == 25)
 				{
-					dprintln("invalid ANSI CSI ?{}{}", m_ansi_state.nums[0], (char)ch);
+					m_show_cursor = (ch == 'h');
 					return reset_ansi();
 				}
-				m_show_cursor = (ch == 'h');
+				reset_ansi();
-				return reset_ansi();
+				dprintln("invalid ANSI CSI ?{}{}", m_ansi_state.nums[0], (char)ch);
+				return;
 			default:
+				reset_ansi();
 				dprintln("Unsupported ANSI CSI character {}", ch);
-				return reset_ansi();
+				return;
 		}
 	}