drm/panfrost: Job should reference MMU not file_priv

For a while now it's been allowed for a MMU context to outlive it's
corresponding panfrost_priv, however the job structure still references
panfrost_priv to get hold of the MMU context. If panfrost_priv has been
freed this is a use-after-free which I've been able to trigger resulting
in a splat.

To fix this, drop the reference to panfrost_priv in the job structure
and add a direct reference to the MMU structure which is what's actually
needed.

Fixes: 7fdc48cc63a3 ("drm/panfrost: Make sure MMU context lifetime is not bound to panfrost_priv")
Signed-off-by: Steven Price <steven.price@arm.com>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220519152003.81081-1-steven.price@arm.com

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/gpu/drm/panfrost/panfrost_job.h b/drivers/gpu/drm/panfrost/panfrost_job.h
index 77e6d0e6f612..8becc1ba0eb9 100644
--- a/drivers/gpu/drm/panfrost/panfrost_job.h
+++ b/drivers/gpu/drm/panfrost/panfrost_job.h
@@ -17,7 +17,7 @@ struct panfrost_job {
 	struct kref refcount;
 
 	struct panfrost_device *pfdev;
-	struct panfrost_file_priv *file_priv;
+	struct panfrost_mmu *mmu;
 
 	/* Fence to be signaled by IRQ handler when the job is complete. */
 	struct dma_fence *done_fence;