From a7b85d2aa63ed09cd5a4a640772b3272f5ac7caa Mon Sep 17 00:00:00 2001 From: Keith Packard Date: Sun, 10 Jul 2011 13:12:17 -0700 Subject: [PATCH] drm/i915: Clean up i915_driver_load failure path i915_driver_load adds a write-combining MTRR region for the GTT aperture to improve memory speeds through the aperture. If i915_driver_load fails after this, it would not have cleaned up the MTRR. This shouldn't cause any problems, except for consuming an MTRR register. Still, it's best to clean up completely in the failure path, which is easily done by calling mtrr_del if the mtrr was successfully allocated. i915_driver_load calls i915_gem_load which register i915_gem_inactive_shrink. If i915_driver_load fails after calling i915_gem_load, the shrinker will be left registered. When called, it will access freed memory and crash. The fix is to unregister the shrinker in the failure path using code duplicated from i915_driver_unload. i915_driver_load also has some incorrect gotos in the error cleanup paths: * After failing to initialize the GTT (which cannot happen, btw, intel_gtt_get returns a fixed (non-NULL) value), it tries to free the uninitialized WC IO mapping. Fixed this by changing the target from out_iomapfree to out_rmmap Signed-off-by: Keith Packard Tested-by: Lin Ming --- drivers/gpu/drm/i915/i915_dma.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c index e1787022d6c8..296fbd66f0e1 100644 --- a/drivers/gpu/drm/i915/i915_dma.c +++ b/drivers/gpu/drm/i915/i915_dma.c @@ -1943,7 +1943,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags) if (!dev_priv->mm.gtt) { DRM_ERROR("Failed to initialize GTT\n"); ret = -ENODEV; - goto out_iomapfree; + goto out_rmmap; } agp_size = dev_priv->mm.gtt->gtt_mappable_entries << PAGE_SHIFT; @@ -1987,7 +1987,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags) if (dev_priv->wq == NULL) { DRM_ERROR("Failed to create our workqueue.\n"); ret = -ENOMEM; - goto out_iomapfree; + goto out_mtrrfree; } /* enable GEM by default */ @@ -2074,13 +2074,21 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags) return 0; out_gem_unload: + if (dev_priv->mm.inactive_shrinker.shrink) + unregister_shrinker(&dev_priv->mm.inactive_shrinker); + if (dev->pdev->msi_enabled) pci_disable_msi(dev->pdev); intel_teardown_gmbus(dev); intel_teardown_mchbar(dev); destroy_workqueue(dev_priv->wq); -out_iomapfree: +out_mtrrfree: + if (dev_priv->mm.gtt_mtrr >= 0) { + mtrr_del(dev_priv->mm.gtt_mtrr, dev->agp->base, + dev->agp->agp_info.aper_size * 1024 * 1024); + dev_priv->mm.gtt_mtrr = -1; + } io_mapping_free(dev_priv->mm.gtt_mapping); out_rmmap: pci_iounmap(dev->pdev, dev_priv->regs); -- 2.20.1