Merge 5.6-rc3 into tty-next

We want the tty fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/vt/selection.c

@@ -16,6 +16,7 @@
 #include <linux/tty.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
+#include <linux/mutex.h>
 #include <linux/slab.h>
 #include <linux/types.h>
 
@@ -29,6 +30,8 @@
 #include <linux/console.h>
 #include <linux/tty_flip.h>
 
+#include <linux/sched/signal.h>
+
 /* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
 #define isspace(c)	((c) == ' ')
 
@@ -43,6 +46,7 @@ static volatile int sel_start = -1; 	/* cleared by clear_selection */
 static int sel_end;
 static int sel_buffer_lth;
 static char *sel_buffer;
+static DEFINE_MUTEX(sel_lock);
 
 /* clear_selection, highlight and highlight_pointer can be called
    from interrupt (via scrollback/front) */
@@ -189,7 +193,7 @@ int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
 	char *bp, *obp;
 	int i, ps, pe, multiplier;
 	u32 c;
-	int mode;
+	int mode, ret = 0;
 
 	poke_blanked_console();
 
@@ -215,6 +219,7 @@ int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
 	if (ps > pe)	/* make sel_start <= sel_end */
 		swap(ps, pe);
 
+	mutex_lock(&sel_lock);
 	if (sel_cons != vc_cons[fg_console].d) {
 		clear_selection();
 		sel_cons = vc_cons[fg_console].d;
@@ -260,9 +265,10 @@ int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
 			break;
 		case TIOCL_SELPOINTER:
 			highlight_pointer(pe);
-			return 0;
+			goto unlock;
 		default:
-			return -EINVAL;
+			ret = -EINVAL;
+			goto unlock;
 	}
 
 	/* remove the pointer */
@@ -284,7 +290,7 @@ int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
 	else if (new_sel_start == sel_start)
 	{
 		if (new_sel_end == sel_end)	/* no action required */
-			return 0;
+			goto unlock;
 		else if (new_sel_end > sel_end)	/* extend to right */
 			highlight(sel_end + 2, new_sel_end);
 		else				/* contract from right */
@@ -312,7 +318,8 @@ int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
 	if (!bp) {
 		printk(KERN_WARNING "selection: kmalloc() failed\n");
 		clear_selection();
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto unlock;
 	}
 	kfree(sel_buffer);
 	sel_buffer = bp;
@@ -337,7 +344,9 @@ int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
 		}
 	}
 	sel_buffer_lth = bp - sel_buffer;
-	return 0;
+unlock:
+	mutex_unlock(&sel_lock);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(set_selection_kernel);
 
@@ -355,6 +364,7 @@ int paste_selection(struct tty_struct *tty)
 	unsigned int count;
 	struct  tty_ldisc *ld;
 	DECLARE_WAITQUEUE(wait, current);
+	int ret = 0;
 
 	console_lock();
 	poke_blanked_console();
@@ -366,10 +376,17 @@ int paste_selection(struct tty_struct *tty)
 	tty_buffer_lock_exclusive(&vc->port);
 
 	add_wait_queue(&vc->paste_wait, &wait);
+	mutex_lock(&sel_lock);
 	while (sel_buffer && sel_buffer_lth > pasted) {
 		set_current_state(TASK_INTERRUPTIBLE);
+		if (signal_pending(current)) {
+			ret = -EINTR;
+			break;
+		}
 		if (tty_throttled(tty)) {
+			mutex_unlock(&sel_lock);
 			schedule();
+			mutex_lock(&sel_lock);
 			continue;
 		}
 		__set_current_state(TASK_RUNNING);
@@ -378,11 +395,12 @@ int paste_selection(struct tty_struct *tty)
 					      count);
 		pasted += count;
 	}
+	mutex_unlock(&sel_lock);
 	remove_wait_queue(&vc->paste_wait, &wait);
 	__set_current_state(TASK_RUNNING);
 
 	tty_buffer_unlock_exclusive(&vc->port);
 	tty_ldisc_deref(ld);
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(paste_selection);

drivers/tty/vt/vt.c

@@ -937,10 +937,21 @@ static void flush_scrollback(struct vc_data *vc)
 	WARN_CONSOLE_UNLOCKED();
 
 	set_origin(vc);
-	if (vc->vc_sw->con_flush_scrollback)
+	if (vc->vc_sw->con_flush_scrollback) {
 		vc->vc_sw->con_flush_scrollback(vc);
-	else
+	} else if (con_is_visible(vc)) {
+		/*
+		 * When no con_flush_scrollback method is provided then the
+		 * legacy way for flushing the scrollback buffer is to use
+		 * a side effect of the con_switch method. We do it only on
+		 * the foreground console as background consoles have no
+		 * scrollback buffers in that case and we obviously don't
+		 * want to switch to them.
+		 */
+		hide_cursor(vc);
 		vc->vc_sw->con_switch(vc);
+		set_cursor(vc);
+	}
 }
 
 /*

drivers/tty/vt/vt_ioctl.c

@@ -891,15 +891,20 @@ int vt_ioctl(struct tty_struct *tty,
 			return -EINVAL;
 
 		for (i = 0; i < MAX_NR_CONSOLES; i++) {
+			struct vc_data *vcp;
+
 			if (!vc_cons[i].d)
 				continue;
 			console_lock();
-			if (v.v_vlin)
-				vc_cons[i].d->vc_scan_lines = v.v_vlin;
-			if (v.v_clin)
-				vc_cons[i].d->vc_font.height = v.v_clin;
-			vc_cons[i].d->vc_resize_user = 1;
-			vc_resize(vc_cons[i].d, v.v_cols, v.v_rows);
+			vcp = vc_cons[i].d;
+			if (vcp) {
+				if (v.v_vlin)
+					vcp->vc_scan_lines = v.v_vlin;
+				if (v.v_clin)
+					vcp->vc_font.height = v.v_clin;
+				vcp->vc_resize_user = 1;
+				vc_resize(vcp, v.v_cols, v.v_rows);
+			}
 			console_unlock();
 		}
 		break;