From: Thomas Zimmermann tzimmermann@suse.de
commit b693e42921e0220c0d564c55c6cdc680b0f85390 upstream.
Clamp the fbdev surface size of the available maximumi height to avoid failing to init console emulation. An example error is shown below.
bad framebuffer height 2304, should be >= 768 && <= 768 [drm] Initialized simpledrm 1.0.0 20200625 for simple-framebuffer.0 on minor 0 simple-framebuffer simple-framebuffer.0: [drm] *ERROR* fbdev: Failed to setup generic emulation (ret=-22)
This is especially a problem with drivers that have very small screen sizes and cannot over-allocate at all.
v2: * reduce warning level (Ville)
Signed-off-by: Thomas Zimmermann tzimmermann@suse.de Fixes: 11e8f5fd223b ("drm: Add simpledrm driver") Reviewed-by: Ville Syrjälä ville.syrjala@linux.intel.com Reviewed-by: Alex Deucher alexander.deucher@amd.com Reported-by: Amanoel Dawod kernel@amanoeldawod.com Reported-by: Zoltán Kővágó dirty.ice.hu@gmail.com Reported-by: Michael Stapelberg michael+lkml@stapelberg.ch Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: Maxime Ripard maxime@cerno.tech Cc: dri-devel@lists.freedesktop.org Cc: stable@vger.kernel.org # v5.14+ Link: https://patchwork.freedesktop.org/patch/msgid/20211005070355.7680-1-tzimmerm... Signed-off-by: Dave Airlie airlied@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/drm_fb_helper.c | 6 ++++++ 1 file changed, 6 insertions(+)
--- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1506,6 +1506,7 @@ static int drm_fb_helper_single_fb_probe { struct drm_client_dev *client = &fb_helper->client; struct drm_device *dev = fb_helper->dev; + struct drm_mode_config *config = &dev->mode_config; int ret = 0; int crtc_count = 0; struct drm_connector_list_iter conn_iter; @@ -1663,6 +1664,11 @@ static int drm_fb_helper_single_fb_probe /* Handle our overallocation */ sizes.surface_height *= drm_fbdev_overalloc; sizes.surface_height /= 100; + if (sizes.surface_height > config->max_height) { + drm_dbg_kms(dev, "Fbdev over-allocation too large; clamping height to %d\n", + config->max_height); + sizes.surface_height = config->max_height; + }
/* push down into drivers */ ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes);