4.4-stable review patch. If anyone has any objections, please let me know.
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From: Thomas Zimmermann tzimmermann@suse.de
commit c2d311553855395764e2e5bf401d987ba65c2056 upstream.
When calling vmw_fb_set_par(), the mode stored in par->set_mode gets free'd twice. The first free is in vmw_fb_kms_detach(), the second is near the end of vmw_fb_set_par() under the name of 'old_mode'. The mode-setting code only works correctly if the mode doesn't actually change. Removing 'old_mode' in favor of using par->set_mode directly fixes the problem.
Cc: stable@vger.kernel.org Fixes: a278724aa23c ("drm/vmwgfx: Implement fbdev on kms v2") Signed-off-by: Thomas Zimmermann tzimmermann@suse.de Reviewed-by: Deepak Rawat drawat@vmware.com Signed-off-by: Thomas Hellstrom thellstrom@vmware.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/gpu/drm/vmwgfx/vmwgfx_fb.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c @@ -531,11 +531,9 @@ static int vmw_fb_set_par(struct fb_info 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_PVSYNC) }; - struct drm_display_mode *old_mode; struct drm_display_mode *mode; int ret;
- old_mode = par->set_mode; mode = drm_mode_duplicate(vmw_priv->dev, &new_mode); if (!mode) { DRM_ERROR("Could not create new fb mode.\n"); @@ -546,11 +544,7 @@ static int vmw_fb_set_par(struct fb_info mode->vdisplay = var->yres; vmw_guess_mode_timing(mode);
- if (old_mode && drm_mode_equal(old_mode, mode)) { - drm_mode_destroy(vmw_priv->dev, mode); - mode = old_mode; - old_mode = NULL; - } else if (!vmw_kms_validate_mode_vram(vmw_priv, + if (!vmw_kms_validate_mode_vram(vmw_priv, mode->hdisplay * DIV_ROUND_UP(var->bits_per_pixel, 8), mode->vdisplay)) { @@ -613,8 +607,8 @@ static int vmw_fb_set_par(struct fb_info schedule_delayed_work(&par->local_work, 0);
out_unlock: - if (old_mode) - drm_mode_destroy(vmw_priv->dev, old_mode); + if (par->set_mode) + drm_mode_destroy(vmw_priv->dev, par->set_mode); par->set_mode = mode;
drm_modeset_unlock_all(vmw_priv->dev);