Patch "drm/atomic: Unref duplicated drm_atomic_state in drm_atomic_helper_resume()" has been added to the 4.13-stable tree

This is a note to let you know that I've just added the patch titled

drm/atomic: Unref duplicated drm_atomic_state in drm_atomic_helper_resume()

to the 4.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
drm-atomic-unref-duplicated-drm_atomic_state-in-drm_atomic_helper_resume.patch
and it can be found in the queue-4.13 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Jeffy Chen <[email protected]>
Date: Mon, 9 Oct 2017 14:46:41 +0800
Subject: drm/atomic: Unref duplicated drm_atomic_state in drm_atomic_helper_resume()

From: Jeffy Chen <[email protected]>

commit 78279127253a6c36ed8829eb2b7bc28ef48d9717 upstream.

Kmemleak reported memory leak after suspend and resume:
unreferenced object 0xffffffc0e31d8880 (size 128):
comm "bash", pid 181, jiffies 4294763583 (age 24.694s) hex dump (first 32 bytes):

    01 00 00 00 00 00 00 00 00 20 a2 eb c0 ff ff ff  ......... ......
    01 00 00 00 00 00 00 00 80 87 1d e3 c0 ff ff ff  ................
  backtrace:
    [<ffffffc00034bb64>] __save_stack_trace+0x48/0x6c
    [<ffffffc00034c244>] create_object+0x138/0x254
    [<ffffffc0009dd218>] kmemleak_alloc+0x58/0x8c
    [<ffffffc000346de4>] kmem_cache_alloc_trace+0x188/0x254
    [<ffffffc0005af4c0>] drm_atomic_state_alloc+0x3c/0x88
    [<ffffffc000591f0c>] drm_atomic_helper_duplicate_state+0x28/0x158
    [<ffffffc000592098>] drm_atomic_helper_suspend+0x5c/0xf0

Problem here is that we are duplicating the drm_atomic_state in drm_atomic_helper_suspend(), but not unreference it in the resume path.

---
 drivers/gpu/drm/drm_atomic_helper.c |    1 +
 1 file changed, 1 insertion(+)

@@ -2756,6 +2756,7 @@ out:
 		drm_modeset_backoff(&ctx);
 	}
 
+	drm_atomic_state_put(state);
 	drm_modeset_drop_locks(&ctx);
 	drm_modeset_acquire_fini(&ctx);
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.13/drm-atomic-unref-duplicated-drm_atomic_state-in-drm_atomic_helper_resume.patch