Labelled this issue as M54.

For M53, our goal is to stabilize chromeos-5.39. We are seeing BT stack crashing (issue 616458) since the last uprev to 5.39. Instead of doing 5.40 uprev, it might be better to investigate the cause of crashing and pick the patches which fix potential GATT issues in the meantime.

There are 55 commits between release 5.39 and 5.40, and 16 of 55 patches are GATT-related.  Issue 614903  mentioned above can be fixed by cherry-picking http://git.kernel.org/cgit/bluetooth/bluez.git/commit/?id=505f2a42f763062754fdb198574970aba15262c3.

616458 seems related to the firmware, not BlueZ.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/bluez/+/66a047f35c6940fb32bddc349cb75e209640cb38

commit 66a047f35c6940fb32bddc349cb75e209640cb38
Author: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Date: Fri May 06 08:36:28 2016

UPSTREAM: test: Update GATT examples with the new API

BUG= chromium:617128 
TEST=emerge bluez

Change-Id: I05770ed5c85cc5a102f5f2adb320613c5880af76
Reviewed-on: https://chromium-review.googlesource.com/351902
Commit-Ready: Miao-chen Chou <mcchou@chromium.org>
Tested-by: Miao-chen Chou <mcchou@chromium.org>
Reviewed-by: Shyh-In Hwang <josephsih@chromium.org>
Reviewed-by: Rahul Chaturvedi <rkc@chromium.org>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>

[modify] https://crrev.com/66a047f35c6940fb32bddc349cb75e209640cb38/test/example-gatt-server
[modify] https://crrev.com/66a047f35c6940fb32bddc349cb75e209640cb38/test/example-gatt-client
[modify] https://crrev.com/66a047f35c6940fb32bddc349cb75e209640cb38/test/test-gatt-profile

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/bluez/+/d285f607356f73f7989503031561f81e975532d0

commit d285f607356f73f7989503031561f81e975532d0
Author: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Date: Fri Apr 22 09:30:35 2016

UPSTREAM: core/device: Fix not storing GATT attributes

If services has been refreshed the attributes shall be stored so they can
be reloaded properly the next time.

BUG= chromium:617128 
TEST=emerge bluez

Change-Id: Id3d9872ec1e74a249af3d713bc8eab5ca3edddf1
Reviewed-on: https://chromium-review.googlesource.com/351901
Commit-Ready: Miao-chen Chou <mcchou@chromium.org>
Tested-by: Miao-chen Chou <mcchou@chromium.org>
Reviewed-by: Shyh-In Hwang <josephsih@chromium.org>
Reviewed-by: Rahul Chaturvedi <rkc@chromium.org>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>

[modify] https://crrev.com/d285f607356f73f7989503031561f81e975532d0/src/device.c

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/bluez/+/da4b9081f93eced9ff0bbf90f09f0d3d85ae600f

commit da4b9081f93eced9ff0bbf90f09f0d3d85ae600f
Author: Francois Beaufort <beaufort.francois@gmail.com>
Date: Tue Apr 26 08:30:29 2016

UPSTREAM: client: Fix select-attribute behaviour

BUG= chromium:617128 
TEST=emerge

Change-Id: Idfdb00363a66c31ec8f0018d84c9fc6176d0ef2e
Reviewed-on: https://chromium-review.googlesource.com/351900
Commit-Ready: Miao-chen Chou <mcchou@chromium.org>
Tested-by: Miao-chen Chou <mcchou@chromium.org>
Reviewed-by: François Beaufort <fbeaufort@chromium.org>
Reviewed-by: Rahul Chaturvedi <rkc@chromium.org>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>

[modify] https://crrev.com/da4b9081f93eced9ff0bbf90f09f0d3d85ae600f/client/main.c

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/bluez/+/58d9cf6e6ebbb1ce60e6da37943bb252b5c28557

commit 58d9cf6e6ebbb1ce60e6da37943bb252b5c28557
Author: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Date: Mon May 09 11:55:12 2016

UPSTREAM: tools/gatt-service: Update to use new GATT API

This update use of ReadValue and WriteValue to include the options
introduced in the API.

BUG= chromium:617128 
TEST=emerge bluez

Change-Id: Ia494c6a2b0b55c8ab71f153f89ad215699ed07ba
Reviewed-on: https://chromium-review.googlesource.com/351903
Commit-Ready: Miao-chen Chou <mcchou@chromium.org>
Tested-by: Miao-chen Chou <mcchou@chromium.org>
Reviewed-by: Shyh-In Hwang <josephsih@chromium.org>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>

[modify] https://crrev.com/58d9cf6e6ebbb1ce60e6da37943bb252b5c28557/tools/gatt-service.c

Considering that we were not really picking everything from 5.40 due to internal dependency, this issue only track the GATT related cherry-picking.

https://chromium-review.googlesource.com/#/c/351904/ is the only one left, once it is landed, this issue can be closed.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/bluez/+/c15ed3fdcfb8721c7162dc7731d8db3a1980490d

commit c15ed3fdcfb8721c7162dc7731d8db3a1980490d
Author: Mikhail I. Krivtsov <mikhail.krivtsov@gmail.com>
Date: Sat May 14 08:37:30 2016

UPSTREAM: shared/gatt-client: Fix sending confirmation

Confirmation shall be sent from topmost parent only.
Extra confirmation sent by clone confuses remote side.

> ACL Data RX: Handle 69 flags 0x02 dlen 27
      ATT: Handle Value Indication (0x1d) len 22
        Handle: 0x001f
          Data: 68656c6c6f2027302e302e302e303a3532353332
< ACL Data TX: Handle 69 flags 0x00 dlen 5
      ATT: Handle Value Confirmation (0x1e) len 0
< ACL Data TX: Handle 69 flags 0x00 dlen 5
      ATT: Handle Value Confirmation (0x1e) len 0

BUG= chromium:617128 
TEST=emerge bluez

Change-Id: Ibab869f88b2a9bc7499445a1b69d6005a505b14c
Reviewed-on: https://chromium-review.googlesource.com/351904
Commit-Ready: Miao-chen Chou <mcchou@chromium.org>
Tested-by: Miao-chen Chou <mcchou@chromium.org>
Reviewed-by: Shyh-In Hwang <josephsih@chromium.org>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>

[modify] https://crrev.com/c15ed3fdcfb8721c7162dc7731d8db3a1980490d/src/shared/gatt-client.c