From: Chris Wilson Date: Thu, 30 Jan 2020 13:51:36 +0000 (+0000) Subject: drm/i915/fbc: __intel_fbc_cleanup_cfb() may be called multiple times X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=37b7617262bd012359a33deb887947ad7cc989f9;p=linux.git drm/i915/fbc: __intel_fbc_cleanup_cfb() may be called multiple times Avoid releasing the same stolen nodes causing a use-after-free and/or explosions as the self-checks fail, as __intel_fbc_cleanup_cfb() may be called multiple times during module unload. Signed-off-by: Chris Wilson Cc: Ville Syrjälä Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20200130135136.1878646-1-chris@chris-wilson.co.uk --- diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c index 2a3f1333c8ff7..ab676c6756af2 100644 --- a/drivers/gpu/drm/i915/display/intel_fbc.c +++ b/drivers/gpu/drm/i915/display/intel_fbc.c @@ -537,13 +537,15 @@ static void __intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv) { struct intel_fbc *fbc = &dev_priv->fbc; - if (drm_mm_node_allocated(&fbc->compressed_fb)) - i915_gem_stolen_remove_node(dev_priv, &fbc->compressed_fb); + if (!drm_mm_node_allocated(&fbc->compressed_fb)) + return; if (fbc->compressed_llb) { i915_gem_stolen_remove_node(dev_priv, fbc->compressed_llb); kfree(fbc->compressed_llb); } + + i915_gem_stolen_remove_node(dev_priv, &fbc->compressed_fb); } void intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv)