[Intel-gfx] [PATCH] drm/i915: Prevent module unload to avoid random memory corruption

[Chris Wilson]

The i915 driver has quite a few module unload bugs, the known ones at
least have fixes that are targeting 2.6.37. However, in order to
maintain a stable kernel, we should prevent this known random memory
corruption following driver unload. This should have very low impact on
normal users who are unlikely to need to unload the i915 driver.

Suggested-by: Thomas Gleixner <tglx at linutronix.de>
Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
Cc: stable at kernel.org
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_dma.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index c74e4e8..2dd2c93 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -2231,6 +2231,9 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 	dev_priv->mchdev_lock = &mchdev_lock;
 	spin_unlock(&mchdev_lock);
 
+	/* XXX Prevent module unload due to memory corruption bugs. */
+	__module_get(THIS_MODULE);
+
 	return 0;
 
 out_workqueue_free:
-- 
1.7.1