drm/i915: grab dev->struct_mutex around framebuffer_init
We look at gem state (like obj->tiling/obj->stride), we better have
the relevant locks.
Right now this doesn't matter much since most of these checks are
a curtesy to safe buggy userspace, but I'd like to freeze the tiling
once we have framebuffer objects attached. And then locking matters.
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 0bbf921..88e5600 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -7285,14 +7285,21 @@
return ERR_PTR(-ENOMEM);
}
+ ret = i915_mutex_lock_interruptible(dev);
+ if (ret)
+ goto err;
+
ret = intel_framebuffer_init(dev, intel_fb, mode_cmd, obj);
- if (ret) {
- drm_gem_object_unreference_unlocked(&obj->base);
- kfree(intel_fb);
- return ERR_PTR(ret);
- }
+ mutex_unlock(&dev->struct_mutex);
+ if (ret)
+ goto err;
return &intel_fb->base;
+err:
+ drm_gem_object_unreference_unlocked(&obj->base);
+ kfree(intel_fb);
+
+ return ERR_PTR(ret);
}
static u32
@@ -9989,6 +9996,8 @@
int pitch_limit;
int ret;
+ WARN_ON(!mutex_is_locked(&dev->struct_mutex));
+
if (obj->tiling_mode == I915_TILING_Y) {
DRM_DEBUG("hardware does not support tiling Y\n");
return -EINVAL;