The execbuffer handle and exec_link were moved from the object into the vma. As the vma may be unbound and destroyed whilst attempting to reserve the execbuffer objects (either through a forced unbind to fix up a misalignment or through an evict-everything call) we need to prevent the free of the i915_vma itself. Otherwise not only is the list of objects to reserve corrupt, but we continue to reference stale vma entries.
Fixes kernel crash with i-g-t/gem_evict_everything Reported-by: Dan Carpenter <dan.carpen...@oracle.com> Bugzilla; https://bugs.freedesktop.org/show_bug.cgi?id=68298 Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk> Cc: Ben Widawsky <b...@bwidawsk.net> --- drivers/gpu/drm/i915/i915_gem.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index bf32b1e..33bbd69 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -4256,6 +4256,11 @@ void i915_gem_vma_destroy(struct i915_vma *vma) { WARN_ON(vma->node.allocated); list_del(&vma->vma_link); + + /* Keep the vma as a placeholder in the execbuffer reservation lists */ + if (!list_empty(&vma->exec_list)) + return; + kfree(vma); } -- 1.8.4.rc3 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
