DDC operation conflicts with concurrent mode setting. Acquire the
driver's I/O lock in get_modes to prevent this. This change should
have been part of commit 931e3f3a0e99 ("drm/mgag200: Protect
concurrent access to I/O registers with lock"), but apparently got
lost somewhere.Signed-off-by: Thomas Zimmermann <[email protected]> Fixes: 931e3f3a0e99 ("drm/mgag200: Protect concurrent access to I/O registers with lock") Cc: Thomas Zimmermann <[email protected]> Cc: Jocelyn Falempe <[email protected]> Cc: Daniel Vetter <[email protected]> Cc: Dave Airlie <[email protected]> Cc: [email protected] --- drivers/gpu/drm/mgag200/mgag200_mode.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c index abde7655477d..4ad8d62c5631 100644 --- a/drivers/gpu/drm/mgag200/mgag200_mode.c +++ b/drivers/gpu/drm/mgag200/mgag200_mode.c @@ -667,16 +667,26 @@ static void mgag200_disable_display(struct mga_device *mdev) static int mga_vga_get_modes(struct drm_connector *connector) { + struct mga_device *mdev = to_mga_device(connector->dev); struct mga_connector *mga_connector = to_mga_connector(connector); struct edid *edid; int ret = 0; + /* + * Protect access to I/O registers from concurrent modesetting + * by acquiring the I/O-register lock. + */ + mutex_lock(&mdev->rmmio_lock); + edid = drm_get_edid(connector, &mga_connector->i2c->adapter); if (edid) { drm_connector_update_edid_property(connector, edid); ret = drm_add_edid_modes(connector, edid); kfree(edid); } + + mutex_unlock(&mdev->rmmio_lock); + return ret; } -- 2.36.0
