[Devel] [PATCH vz9] drm: Disable modeset by default

[Konstantin Khorenko]

1. VHS and HCI are server products => nice graphical console output is not
   that important.
2. QXL driver is buggy, we face issues with L1 VMs hungs during console writing
   using QXL driver.

=> let's disable framebuffer by default (like we always have "nomodeset"
kernel boot option set).

To reverse the situation, we add "modeset" kernel boot option which
enables back framebuffer drivers usage.

https://pmc.acronis.work/browse/VSTOR-81614

Signed-off-by: Konstantin Khorenko <khorenko at virtuozzo.com>
---
 drivers/video/nomodeset.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/video/nomodeset.c b/drivers/video/nomodeset.c
index 13cc8b719697..1ee9c29d185b 100644
--- a/drivers/video/nomodeset.c
+++ b/drivers/video/nomodeset.c
@@ -5,7 +5,7 @@
 
 #include <video/nomodeset.h>
 
-static bool video_nomodeset;
+static bool video_nomodeset = true;
 
 bool video_firmware_drivers_only(void)
 {
@@ -22,5 +22,16 @@ static int __init disable_modeset(char *str)
 	return 1;
 }
 
+static int __init enable_modeset(char *str)
+{
+	video_nomodeset = false;
+
+	pr_warn("Booted with the modeset parameter. Full framebuffer support is enabled\n");
+
+	return 1;
+}
+
 /* Disable kernel modesetting */
 __setup("nomodeset", disable_modeset);
+/* Enable kernel modesetting */
+__setup("modeset", enable_modeset);
-- 
2.39.3