During driver probe, in i915_driver_register(), if drm_dev_register() fails, the code enters into an error path. In it, a call to drm_dev_unregister() is made as part of cleanup in case drm_dev_register() returns an error. However, this is unnecessary, as in case of an error drm_dev_register() undoes its own setup in its own error path.
Calling drm_dev_unregister() after a failed drm_dev_register() also generates a superfluous WARN_ON() from drm_client_sysrq_unregister(). drm_client_sysrq_register() is only called in drm_dev_register() if there was no error in the latter. drm_dev_unregister() calls drm_client_sysrq_unregister() as it expects to be called after a successful drm_dev_register(), in which case the _sysrq_register() counterpart is called. However, if the call to drm_dev_register() failed, _sysrq_register() is never called; calling drm_dev_unregister() will cause _sysrq_unregister() to be called (unconditionally) with no corresponding _sysrq_register() call before it, which is caught in the aforementioned WARN_ON(). Remove the redundant call to drm_dev_unregister() in case drm_dev_register() returns an error. Signed-off-by: Krzysztof Niemiec <[email protected]> --- drivers/gpu/drm/i915/i915_driver.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c index c10cab38935a..10e16002050a 100644 --- a/drivers/gpu/drm/i915/i915_driver.c +++ b/drivers/gpu/drm/i915/i915_driver.c @@ -638,7 +638,6 @@ static int i915_driver_register(struct drm_i915_private *dev_priv) if (ret) { i915_probe_error(dev_priv, "Failed to register driver for userspace access!\n"); - drm_dev_unregister(&dev_priv->drm); i915_pmu_unregister(dev_priv); i915_gem_driver_unregister(dev_priv); return ret; -- 2.45.2
