[xenial] SRU: Bluetooth: increase timeout for le auto connections

[Seth Forshee]

On Fri, Nov 10, 2017 at 01:11:05PM +0100, Konrad Zapalowicz wrote:
> SRU Justification:
> 
> [Impact]
> 
> Not possible to pair BLE remote devices such as sensors and such with
> Ubuntu when the host system uses BT+WiFi combo SoC. The connection
> attempt is disturbed with a timeout.
> 
> [Fix]
> 
> It has been fixed by increasing the timeout value from 2 seconds to
> 4 seconds. It is enough for the events to reach the stack (measured
> that it takes between 3 and 3.5 seconds).
> 
> [Testcase]
> 
> Tested with the device that failed to connect to Ubuntu Core gateway.
> It fails w/o the patch, it connects just fine with the patch applied.
> 
> [Regression Potential]
> 
> Very small. The increased timeout is taken into consideration only for
> new and scan report triggered connections. It will not make any already
> working device to fail to pair.
> 
> [Other Info]
> 
> The bug has been discussed and fixed here:
> 
> https://marc.info/?l=linux-bluetooth&m=150824844606937&w=2
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/commit/?id=1f01d8be0e6a04bd682a55f6d50c14c1679e7571
> 
> The patch has been accepted by the upstream and will be a part of the
> next kernel release. Currently in the bluetooth-next tree.

Typically you should include this information in a cover letter (use
'git format-patch --cover-letter ...', then edit the cover letter and
send the patches with 'git send-email'). It's more difficult to apply
patches when sent like this, however it's not my job to apply this patch
so I'll let others tell you whether or not you should resend it.

> [Patch]
> 
> From 2d5a130b6cf6cbf992f9a7a66dcab8ab4e8e15f9 Mon Sep 17 00:00:00 2001
> From: =?UTF-8?q?Konrad=20Zapa=C5=82owicz?= <konrad.zapalowicz at canonical.com>
> Date: Tue, 17 Oct 2017 15:53:49 +0200
> Subject: [PATCH] [xenial] (upstream) Bluetooth: increase timeout for le auto
>  connections
> MIME-Version: 1.0
> Content-Type: text/plain; charset=UTF-8
> Content-Transfer-Encoding: 8bit
> 
> BugLink: https://bugs.launchpad.net/bugs/1731467
> 
> This patch increases the connection timeout for LE connections that are
> triggered by the advertising report to 4 seconds.
> 
> It has been observed that devices equipped with wifi+bt combo SoC fail
> to create a connection with BLE devices due to their coexistence issues.
> Increasing this timeout gives them enough time to complete the
> connection with success.
> 
> Signed-off-by: Konrad Zapałowicz <konrad.zapalowicz at canonical.com>
> Signed-off-by: Marcel Holtmann <marcel at holtmann.org>
> (cherry picked from commit 1f01d8be0e6a04bd682a55f6d50c14c1679e7571)

Since this patch is only in linux-next right now, this should be changed
to read:

 (cherry picked from commit 1f01d8be0e6a04bd682a55f6d50c14c1679e7571 linux-next)

Otherwise we assume the sha1 is from Linus' tree, but it doesn't exist
there yet. With that change:

Acked-by: Seth Forshee <seth.forshee at canonical.com>

But again, I'll let others say whether or not you need to resend to fix
this.

Thanks,
Seth