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From:   Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Date:   Tue, 30 Oct 2018 14:52:24 +0200
Message-ID: <CABBYNZLd_ms7SbjEx2t_a52KVwBDVJMhVhv8YXM=Dvw8tq5WjA@mail.gmail.com>
Subject: Re: [PATCH] gatt: Fix double att_disconnected issue on disconnection
To:     Yunhan Wang <yunhanw@google.com>
Cc:     "linux-bluetooth@vger.kernel.org" <linux-bluetooth@vger.kernel.org>
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Sender: linux-bluetooth-owner@vger.kernel.org
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Hi Yunhan,

On Tue, Oct 30, 2018 at 9:21 AM Yunhan Wang <yunhanw@google.com> wrote:
>
> Hi, Luiz
>
> I am still seeing the bluetoothd crash when disconnect happens on this
> issue. Here I reproduce using btvirt and add characteristic with
> indicate in ble peripheral, put notify on for this characteristic in
> ble central
> crash is as below:
>
> #0  __memcmp_sse4_1 () at ../sysdeps/x86_64/multiarch/memcmp-sse4.S:943
> #1  0x00005555555cfd3a in bacmp (ba2=3D0x7fffffffdfe9, ba1=3D0xb) at
> bluez/repo/lib/bluetooth.h:317
> #2  device_addr_type_cmp (a=3D0x0, b=3D0x7fffffffdfe9) at
> /bluez/repo/src/device.c:4216
> #3  0x00007ffff7b2e3d1 in g_slist_find_custom () from
> /lib/x86_64-linux-gnu/libglib-2.0.so.0
> #4  0x00005555555bcf18 in btd_adapter_find_device (adapter=3D<optimized
> out>, dst=3Ddst@entry=3D0x555555876038, bdaddr_type=3D<optimized out>)
>     at bluez/repo/src/adapter.c:845
> #5  0x00005555555ab89e in att_disconnected (err=3D<optimized out>,
> user_data=3D0x555555876030)
>     at bluez/repo/src/gatt-database.c:329
> #6  0x00005555555eabb8 in queue_foreach (queue=3D0x555555874460,
> function=3Dfunction@entry=3D0x5555555ee600 <disconn_handler>,
> user_data=3D0x68)
>     at bluez/repo/src/shared/queue.c:220
> #7  0x00005555555ef829 in disconnect_cb (io=3D<optimized out>,
> user_data=3D0x5555558742a0)
>     at /bluez/repo/src/shared/att.c:592
> #8  0x00005555555f89b3 in watch_callback (channel=3D<optimized out>,
> cond=3D<optimized out>, user_data=3D<optimized out>)
>     at /bluez/repo/src/shared/io-glib.c:170
> #9  0x00007ffff7b0fe35 in g_main_context_dispatch () from
> /lib/x86_64-linux-gnu/libglib-2.0.so.0
> #10 0x00007ffff7b10200 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so=
.0
> #11 0x00007ffff7b10512 in g_main_loop_run () from
> /lib/x86_64-linux-gnu/libglib-2.0.so.0
> #12 0x0000555555572238 in main (argc=3D<optimized out>, argv=3D<optimized
> out>) at /bluez/repo/src/main.c:808
>
> Peripheral:
>
> [bluetooth]# select 00:AA:01:01:00:24
> Controller 00:AA:01:01:00:24 N0001 [default]
> [bluetooth]# system-alias N0001
> Changing N0001 succeeded
> [bluetooth]# power on
> Changing power on succeeded
> [bluetooth]# name N0001
> [bluetooth]# uuids FEAF
> [bluetooth]# discoverable on

Hmm, are you connecting over BR/EDR, normally you would need to
advertise in order to connect? I guess I haven't tried that, but at
least with LE Im pretty sure it doesn't crash anymore, it is worth
checking if it is not connecting on multiple bearers at the same time
though.

> [bluetooth]# back
> [bluetooth]# register-service 0000feaf-0000-1000-8000-00805f9b34fb
> [NEW] Primary Service
> /org/bluez/app/service0x562f48a31860
> 0000feaf-0000-1000-8000-00805f9b34fb
> Nest Labs Inc.
> [/org/bluez/app/service0x562f48a31860] Primary (yes/no): yees
> Invalid option: yees
> [DEL] Primary Service
> /org/bluez/app/service0x562f48a31860
> 0000feaf-0000-1000-8000-00805f9b34fb
> Nest Labs Inc.
> [bluetooth]# register-service 0000feaf-0000-1000-8000-00805f9b34fb
> [NEW] Primary Service
> /org/bluez/app/service0x562f48a34e70
> 0000feaf-0000-1000-8000-00805f9b34fb
> Nest Labs Inc.
> [/org/bluez/app/service0x562f48a34e70] Primary (yes/no): yes
>
> [bluetooth]# register-characteristic
> 18ee2ef5-263d-4559-959f-4f9c429f9d11 read,indicate
> [NEW] Characteristic
> /org/bluez/app/service0x562f48a34e70/chrc0x562f48a437c0
> 18ee2ef5-263d-4559-959f-4f9c429f9d11
> Vendor specific
> [/org/bluez/app/service0x562f48a34e70/chrc0x562f48a437c0] Enter value: 1
>
> [bluetooth]# register-application
> [CHG] Controller 00:AA:01:01:00:24 UUIDs: 00001800-0000-1000-8000-00805f9=
b34fb
> [CHG] Controller 00:AA:01:01:00:24 UUIDs: 00001801-0000-1000-8000-00805f9=
b34fb
> [CHG] Controller 00:AA:01:01:00:24 UUIDs: 0000110e-0000-1000-8000-00805f9=
b34fb
> [CHG] Controller 00:AA:01:01:00:24 UUIDs: 00001200-0000-1000-8000-00805f9=
b34fb
> [CHG] Controller 00:AA:01:01:00:24 UUIDs: 0000110c-0000-1000-8000-00805f9=
b34fb
> [CHG] Controller 00:AA:01:01:00:24 UUIDs: 0000feaf-0000-1000-8000-00805f9=
b34fb
> Application registered
> [CHG] Controller 00:AA:01:01:00:24 UUIDs: 00001800-0000-1000-8000-00805f9=
b34fb
> [CHG] Controller 00:AA:01:01:00:24 UUIDs: 00001801-0000-1000-8000-00805f9=
b34fb
> [CHG] Controller 00:AA:01:01:00:24 UUIDs: 0000110e-0000-1000-8000-00805f9=
b34fb
> [CHG] Controller 00:AA:01:01:00:24 UUIDs: 00001200-0000-1000-8000-00805f9=
b34fb
> [CHG] Controller 00:AA:01:01:00:24 UUIDs: 0000110c-0000-1000-8000-00805f9=
b34fb
> [CHG] Controller 00:AA:01:01:00:24 UUIDs: 0000feaf-0000-1000-8000-00805f9=
b34fb
> [bluetooth]# back
>
> [bluetooth]# advertise peripheral
> [CHG] Controller 00:AA:01:01:00:24 SupportedInstances: 0x04
> [CHG] Controller 00:AA:01:01:00:24 ActiveInstances: 0x01
> Advertising object registered
> UUID: (FEAF)
> Tx Power: off
> LocalName: N0001
> Apperance: off
> Discoverable: on
> [CHG] Controller 00:AA:01:00:00:23 Powered: yes
> [CHG] Controller 00:AA:01:00:00:23 Discovering: yes
> [CHG] Controller 00:AA:01:00:00:23 Discovering: no
> [CHG] Controller 00:AA:01:00:00:23 Discovering: yes
> [CHG] Device 00:AA:01:00:00:23 Connected: yes
> [NEW] Primary Service
> /org/bluez/hci2/dev_00_AA_01_00_00_23/service0006
> 00001801-0000-1000-8000-00805f9b34fb
> Generic Attribute Profile
> [NEW] Characteristic
> /org/bluez/hci2/dev_00_AA_01_00_00_23/service0006/char0007
> 00002a05-0000-1000-8000-00805f9b34fb
> Service Changed
> [NEW] Descriptor
> /org/bluez/hci2/dev_00_AA_01_00_00_23/service0006/char0007/desc0009
> 00002902-0000-1000-8000-00805f9b34fb
> Client Characteristic Configuration
> [CHG] Device 00:AA:01:00:00:23 ServicesResolved: yes
>
>
> Central:
>
> [bluetooth]# select 00:AA:01:00:00:23
> Discovery stopped
> [bluetooth]# scan on
> Discovery started
> [CHG] Controller 00:AA:01:00:00:23 Discovering: yes
> [bluetooth]# connect 00:AA:01:01:00:24
> Attempting to connect to 00:AA:01:01:00:24
> [CHG] Device 00:AA:01:01:00:24 Connected: yes
> Connection successful
> [CHG] Device 00:AA:01:01:00:24 UUIDs: 00001800-0000-1000-8000-00805f9b34f=
b
> [CHG] Device 00:AA:01:01:00:24 UUIDs: 00001801-0000-1000-8000-00805f9b34f=
b
> [NEW] Primary Service
> /org/bluez/hci1/dev_00_AA_01_01_00_24/service0006
> 00001801-0000-1000-8000-00805f9b34fb
> Generic Attribute Profile
> [NEW] Characteristic
> /org/bluez/hci1/dev_00_AA_01_01_00_24/service0006/char0007
> 00002a05-0000-1000-8000-00805f9b34fb
> Service Changed
> [NEW] Descriptor
> /org/bluez/hci1/dev_00_AA_01_01_00_24/service0006/char0007/desc0009
> 00002902-0000-1000-8000-00805f9b34fb
> Client Characteristic Configuration
> [NEW] Primary Service
> /org/bluez/hci1/dev_00_AA_01_01_00_24/service000d
> 0000feaf-0000-1000-8000-00805f9b34fb
> Nest Labs Inc.
> [NEW] Characteristic
> /org/bluez/hci1/dev_00_AA_01_01_00_24/service000d/char000e
> 18ee2ef5-263d-4559-959f-4f9c429f9d11
> Vendor specific
> [CHG] Device 00:AA:01:01:00:24 UUIDs: 00001800-0000-1000-8000-00805f9b34f=
b
> [CHG] Device 00:AA:01:01:00:24 UUIDs: 00001801-0000-1000-8000-00805f9b34f=
b
> [CHG] Device 00:AA:01:01:00:24 UUIDs: 0000feaf-0000-1000-8000-00805f9b34f=
b
> [CHG] Device 00:AA:01:01:00:24 ServicesResolved: yes
>
> [N0001]# select-attribute 00002a05-0000-1000-8000-00805f9b34fb
> [CHG] Device 00:AA:01:01:00:24 RSSI: 127
> [CHG] Device 00:AA:01:01:00:24 AdvertisingFlags:
>   06                                               .
> [N0001:/service0006/char0007]# notify on
> [CHG] Attribute
> /org/bluez/hci1/dev_00_AA_01_01_00_24/service0006/char0007 Notifying:
> yes
> Notify started
>
>
> [N0001]# disconnect 00:AA:01:01:00:24
> Attempting to disconnect from 00:AA:01:01:00:24
> [CHG] Device 00:AA:01:01:00:24 ServicesResolved: no
> Successful disconnected

After this all I got was:

bluetoothd[31908]: src/gatt-client.c:btd_gatt_client_disconnected()
Device disconnected. Cleaning up.
bluetoothd[31908]: src/device.c:att_disconnected_cb() Automatic
connection disabled
bluetoothd[31908]: src/gatt-database.c:btd_gatt_database_att_disconnected()
bluetoothd[31908]: src/gatt-database.c:att_disconnected()
bluetoothd[31908]: attrib/gattrib.c:g_attrib_unref() 0x99b3ba0: g_attrib_un=
ref=3D0

>
> Thanks
> Best wishes
> Yunhan
> On Mon, Oct 29, 2018 at 1:05 PM Yunhan Wang <yunhanw@google.com> wrote:
> >
> > Hi, Luiz
> >
> > Great, thanks. It is working now.
> >
> > Best wishes
> > Yunhan
> > On Mon, Oct 29, 2018 at 6:28 AM Luiz Augusto von Dentz
> > <luiz.dentz@gmail.com> wrote:
> > >
> > > Hi Yunhan,
> > > On Fri, Oct 26, 2018 at 5:00 AM Yunhan Wang <yunhanw@google.com> wrot=
e:
> > > >
> > > > Hi, Luiz
> > > >
> > > > On Thu, Oct 25, 2018 at 2:41 PM Luiz Augusto von Dentz
> > > > <luiz.dentz@gmail.com> wrote:
> > > > >
> > > > > Hi Yunhan,
> > > > > On Fri, Oct 26, 2018 at 12:06 AM Yunhan Wang <yunhanw@google.com>=
 wrote:
> > > > > >
> > > > > > Hi, Luiz
> > > > > >
> > > > > > I am using latest bluez master without any change for this issu=
e, I
> > > > > > think I am not missing any changes....The issue is there.
> > > > >
> > > > > Then we have a problem on bt_att, but that is tracking if the han=
dler
> > > > > is removed so I wonder how it is still reproducible for you.
> > > > >
> > > > It is reproducible using real ble dongles, It is also reproducible
> > > > using btvirt.....
> > > > Using btvirt -L -l2  and bluetoothctl
> > > >
> > > > Following the below instructions, when central issue ble disconnect=
ion
> > > > to peripheral, the bluetoothd would crash as I show before.
> > > >
> > > > Peripheral:
> > > >
> > > > [bluetooth]# select 00:AA:01:01:00:24
> > > > Controller 00:AA:01:01:00:24 N0001 [default]
> > > > [bluetooth]# system-alias N0001
> > > > Changing N0001 succeeded
> > > > [bluetooth]# power on
> > > > Changing power on succeeded
> > > > [bluetooth]# name N0001
> > > > [bluetooth]# uuids FEAF
> > > > [bluetooth]# discoverable on
> > > > [bluetooth]# back
> > > > [bluetooth]# register-service 0000feaf-0000-1000-8000-00805f9b34fb
> > > > [NEW] Primary Service
> > > > /org/bluez/app/service0x562f48a31860
> > > > 0000feaf-0000-1000-8000-00805f9b34fb
> > > > Nest Labs Inc.
> > > > [/org/bluez/app/service0x562f48a31860] Primary (yes/no): yees
> > > > Invalid option: yees
> > > > [DEL] Primary Service
> > > > /org/bluez/app/service0x562f48a31860
> > > > 0000feaf-0000-1000-8000-00805f9b34fb
> > > > Nest Labs Inc.
> > > > [bluetooth]# register-service 0000feaf-0000-1000-8000-00805f9b34fb
> > > > [NEW] Primary Service
> > > > /org/bluez/app/service0x562f48a34e70
> > > > 0000feaf-0000-1000-8000-00805f9b34fb
> > > > Nest Labs Inc.
> > > > [/org/bluez/app/service0x562f48a34e70] Primary (yes/no): yes
> > > >
> > > > [bluetooth]# register-characteristic
> > > > 18ee2ef5-263d-4559-959f-4f9c429f9d11 read,write
> > > > [NEW] Characteristic
> > > > /org/bluez/app/service0x562f48a34e70/chrc0x562f48a437c0
> > > > 18ee2ef5-263d-4559-959f-4f9c429f9d11
> > > > Vendor specific
> > > > [/org/bluez/app/service0x562f48a34e70/chrc0x562f48a437c0] Enter val=
ue: 1
> > > >
> > > > [bluetooth]# register-application
> > > > [CHG] Controller 00:AA:01:01:00:24 UUIDs: 00001800-0000-1000-8000-0=
0805f9b34fb
> > > > [CHG] Controller 00:AA:01:01:00:24 UUIDs: 00001801-0000-1000-8000-0=
0805f9b34fb
> > > > [CHG] Controller 00:AA:01:01:00:24 UUIDs: 0000110e-0000-1000-8000-0=
0805f9b34fb
> > > > [CHG] Controller 00:AA:01:01:00:24 UUIDs: 00001200-0000-1000-8000-0=
0805f9b34fb
> > > > [CHG] Controller 00:AA:01:01:00:24 UUIDs: 0000110c-0000-1000-8000-0=
0805f9b34fb
> > > > [CHG] Controller 00:AA:01:01:00:24 UUIDs: 0000feaf-0000-1000-8000-0=
0805f9b34fb
> > > > Application registered
> > > > [CHG] Controller 00:AA:01:01:00:24 UUIDs: 00001800-0000-1000-8000-0=
0805f9b34fb
> > > > [CHG] Controller 00:AA:01:01:00:24 UUIDs: 00001801-0000-1000-8000-0=
0805f9b34fb
> > > > [CHG] Controller 00:AA:01:01:00:24 UUIDs: 0000110e-0000-1000-8000-0=
0805f9b34fb
> > > > [CHG] Controller 00:AA:01:01:00:24 UUIDs: 00001200-0000-1000-8000-0=
0805f9b34fb
> > > > [CHG] Controller 00:AA:01:01:00:24 UUIDs: 0000110c-0000-1000-8000-0=
0805f9b34fb
> > > > [CHG] Controller 00:AA:01:01:00:24 UUIDs: 0000feaf-0000-1000-8000-0=
0805f9b34fb
> > > > [bluetooth]# back
> > > >
> > > > [bluetooth]# advertise peripheral
> > > > [CHG] Controller 00:AA:01:01:00:24 SupportedInstances: 0x04
> > > > [CHG] Controller 00:AA:01:01:00:24 ActiveInstances: 0x01
> > > > Advertising object registered
> > > > UUID: (FEAF)
> > > > Tx Power: off
> > > > LocalName: N0001
> > > > Apperance: off
> > > > Discoverable: on
> > > > [CHG] Controller 00:AA:01:00:00:23 Powered: yes
> > > > [CHG] Controller 00:AA:01:00:00:23 Discovering: yes
> > > > [CHG] Controller 00:AA:01:00:00:23 Discovering: no
> > > > [CHG] Controller 00:AA:01:00:00:23 Discovering: yes
> > > > [CHG] Device 00:AA:01:00:00:23 Connected: yes
> > > > [NEW] Primary Service
> > > > /org/bluez/hci2/dev_00_AA_01_00_00_23/service0006
> > > > 00001801-0000-1000-8000-00805f9b34fb
> > > > Generic Attribute Profile
> > > > [NEW] Characteristic
> > > > /org/bluez/hci2/dev_00_AA_01_00_00_23/service0006/char0007
> > > > 00002a05-0000-1000-8000-00805f9b34fb
> > > > Service Changed
> > > > [NEW] Descriptor
> > > > /org/bluez/hci2/dev_00_AA_01_00_00_23/service0006/char0007/desc0009
> > > > 00002902-0000-1000-8000-00805f9b34fb
> > > > Client Characteristic Configuration
> > > > [CHG] Device 00:AA:01:00:00:23 ServicesResolved: yes
> > > >
> > > >
> > > > Central:
> > > >
> > > > [bluetooth]# select 00:AA:01:00:00:23
> > > > Discovery stopped
> > > > [bluetooth]# scan on
> > > > Discovery started
> > > > [CHG] Controller 00:AA:01:00:00:23 Discovering: yes
> > > > [bluetooth]# connect 00:AA:01:01:00:24
> > > > Attempting to connect to 00:AA:01:01:00:24
> > > > [CHG] Device 00:AA:01:01:00:24 Connected: yes
> > > > Connection successful
> > > > [CHG] Device 00:AA:01:01:00:24 UUIDs: 00001800-0000-1000-8000-00805=
f9b34fb
> > > > [CHG] Device 00:AA:01:01:00:24 UUIDs: 00001801-0000-1000-8000-00805=
f9b34fb
> > > > [NEW] Primary Service
> > > > /org/bluez/hci1/dev_00_AA_01_01_00_24/service0006
> > > > 00001801-0000-1000-8000-00805f9b34fb
> > > > Generic Attribute Profile
> > > > [NEW] Characteristic
> > > > /org/bluez/hci1/dev_00_AA_01_01_00_24/service0006/char0007
> > > > 00002a05-0000-1000-8000-00805f9b34fb
> > > > Service Changed
> > > > [NEW] Descriptor
> > > > /org/bluez/hci1/dev_00_AA_01_01_00_24/service0006/char0007/desc0009
> > > > 00002902-0000-1000-8000-00805f9b34fb
> > > > Client Characteristic Configuration
> > > > [NEW] Primary Service
> > > > /org/bluez/hci1/dev_00_AA_01_01_00_24/service000d
> > > > 0000feaf-0000-1000-8000-00805f9b34fb
> > > > Nest Labs Inc.
> > > > [NEW] Characteristic
> > > > /org/bluez/hci1/dev_00_AA_01_01_00_24/service000d/char000e
> > > > 18ee2ef5-263d-4559-959f-4f9c429f9d11
> > > > Vendor specific
> > > > [CHG] Device 00:AA:01:01:00:24 UUIDs: 00001800-0000-1000-8000-00805=
f9b34fb
> > > > [CHG] Device 00:AA:01:01:00:24 UUIDs: 00001801-0000-1000-8000-00805=
f9b34fb
> > > > [CHG] Device 00:AA:01:01:00:24 UUIDs: 0000feaf-0000-1000-8000-00805=
f9b34fb
> > > > [CHG] Device 00:AA:01:01:00:24 ServicesResolved: yes
> > > >
> > > > [N0001]# disconnect 00:AA:01:01:00:24
> > > > Attempting to disconnect from 00:AA:01:01:00:24
> > > > [CHG] Device 00:AA:01:01:00:24 ServicesResolved: no
> > > > Successful disconnected
> > >
> > > It should be fixed now, the problem was that the bt_gatt_server was
> > > set to NULL already thus the bt_att_unregister_disconnect did nothing=
,
> > > Ive might have tested a version were I passed bt_att directly but
> > > later I changed to use bt_gatt_server to access the bt_att instance
> > > from btd_device.
> > >
> > > >
> > > > > > It is not for chrome os. I am currently trying bring up bluez v=
ersion
> > > > > > from commit in Jan 19 11:37:07 2018 to latest master in Open we=
ave
> > > > > > project(https://github.com/openweave/openweave-core/blob/master=
/repos.conf),
> > > > > > where we are using BLE for weave pairing in iot products, and c=
reate
> > > > > > two GATT characteristics for Tx and Rx and the TCP-like control
> > > > > > protocol  to control BLE packet flow. Periodically I would sync=
 Bluez
> > > > > > revision in openweave against Bluez Upstream.
> > > > >
> > > > > All major mobile OS support LE L2CAP CoC channels, no idea why
> > > > > companies want to keep using GATT for emulating serial like
> > > > > communication special when L2CAP does have support for fragmentat=
ion
> > > > > and flow control.
> > > > >
> > > > Yes, L2CAP do have support for fragmentation and flow control, but =
for
> > > > some platforms, it may not have bluez, and its L2CAP is not good, t=
hen
> > > > GATT layer fragmentation and flow control is needed. In addition, t=
he
> > > > L2CAP API is available on neither Android nor iOS when we did this
> > > > implementation in the past...then GATT layer fragmentation and flow
> > > > control is also needed.
> > >
> > > Sure, though moving to L2CAP is a lot simpler... anyway it was just a
> > > recommendation given that L2CAP is now supported.
> > >
> > > > Thanks
> > > > Best wishes
> > > > Yunhan
> > > > > > Thanks
> > > > > > Best wishes
> > > > > > Yunhan
> > > > > >
> > > > > > On Thu, Oct 25, 2018 at 1:22 PM Luiz Augusto von Dentz
> > > > > > <luiz.dentz@gmail.com> wrote:
> > > > > > >
> > > > > > > Hi Yunhan,
> > > > > > >
> > > > > > > On Thu, Oct 25, 2018 at 9:24 PM Luiz Augusto von Dentz
> > > > > > > <luiz.dentz@gmail.com> wrote:
> > > > > > > >
> > > > > > > > Hi Yunhan,
> > > > > > > >
> > > > > > > > We might be better of removing the handler altogether and j=
ust leave device.c handler instead then.
> > > > > > > >
> > > > > > > > On Thu, 25 Oct 2018, 20:19 Yunhan Wang, <yunhanw@google.com=
> wrote:
> > > > > > > >>
> > > > > > > >> Hi, Luiz
> > > > > > > >>
> > > > > > > >> Actually before I submit my patch, I tried your way to unr=
egister the
> > > > > > > >> handler, it is failing. That is why I use random address c=
heck in
> > > > > > > >> btd_gatt_database_att_disconnected to workaround this issu=
e.
> > > > > > > >>
> > > > > > > >> Thanks
> > > > > > > >> Best wishes
> > > > > > > >> Yunhan
> > > > > > > >>
> > > > > > > >>
> > > > > > > >>
> > > > > > > >> On Thu, Oct 25, 2018 at 10:49 AM Yunhan Wang <yunhanw@goog=
le.com> wrote:
> > > > > > > >> >
> > > > > > > >> > Hi, Luiz
> > > > > > > >> >
> > > > > > > >> > Just have a test with your patch in master branch, both =
crashes are
> > > > > > > >> > still there, and att_disconnected has been called for tw=
o times even
> > > > > > > >> > though unregistering the handler....
> > > > > > >
> > > > > > > Actually you may be missing the following patch:
> > > > > > >
> > > > > > > commit 261cf78db4be79a0f7d44798a57730b159c9be91
> > > > > > > Author: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> > > > > > > Date:   Mon Oct 23 14:13:59 2017 +0300
> > > > > > >
> > > > > > >     shared/att: Fix crash when calling disconnect handlers
> > > > > > >
> > > > > > > This is quite old btw, what version is Chrome OS shipping?
> > > > > > >
> > > > > > > >> > Thanks
> > > > > > > >> > Best wishes
> > > > > > > >> > Yunhan
> > > > > > > >> >
> > > > > > > >> > Program received signal SIGSEGV, Segmentation fault.
> > > > > > > >> > btd_adapter_find_device (adapter=3D0x72657664612f6372,
> > > > > > > >> > dst=3Ddst@entry=3D0x555555872998, bdaddr_type=3D0 '\000'=
)
> > > > > > > >> >     at bluez/repo/src/adapter.c:845
> > > > > > > >> > 845 list =3D g_slist_find_custom(adapter->devices, &addr=
,
> > > > > > > >> > (gdb) bt
> > > > > > > >> > #0  btd_adapter_find_device (adapter=3D0x72657664612f637=
2,
> > > > > > > >> > dst=3Ddst@entry=3D0x555555872998, bdaddr_type=3D0 '\000'=
)
> > > > > > > >> >     at bluez/repo/src/adapter.c:845
> > > > > > > >> > #1  0x00005555555ab890 in att_disconnected (err=3D<optim=
ized out>,
> > > > > > > >> > user_data=3D0x555555872990)
> > > > > > > >> >     at bluez/repo/src/gatt-database.c:329
> > > > > > > >> > #2  0x00005555555eaba8 in queue_foreach (queue=3D0x55555=
585de60,
> > > > > > > >> > function=3Dfunction@entry=3D0x5555555ee5f0 <disconn_hand=
ler>,
> > > > > > > >> > user_data=3D0x68)
> > > > > > > >> >     at bluez/repo/src/shared/queue.c:220
> > > > > > > >> > #3  0x00005555555ef819 in disconnect_cb (io=3D<optimized=
 out>,
> > > > > > > >> > user_data=3D0x555555869d50)
> > > > > > > >> >     at bluez/repo/src/shared/att.c:592
> > > > > > > >> > #4  0x00005555555f89a3 in watch_callback (channel=3D<opt=
imized out>,
> > > > > > > >> > cond=3D<optimized out>, user_data=3D<optimized out>)
> > > > > > > >> >     at bluez/repo/src/shared/io-glib.c:170
> > > > > > > >> > #5  0x00007ffff7b0fe35 in g_main_context_dispatch () fro=
m
> > > > > > > >> > /lib/x86_64-linux-gnu/libglib-2.0.so.0
> > > > > > > >> > #6  0x00007ffff7b10200 in ?? () from /lib/x86_64-linux-g=
nu/libglib-2.0.so.0
> > > > > > > >> > #7  0x00007ffff7b10512 in g_main_loop_run () from
> > > > > > > >> > /lib/x86_64-linux-gnu/libglib-2.0.so.0
> > > > > > > >> > #8  0x0000555555572238 in main (argc=3D<optimized out>, =
argv=3D<optimized
> > > > > > > >> > out>) at bluez/repo/src/main.c:808
> > > > > > > >> >
> > > > > > > >> >
> > > > > > > >> > Program received signal SIGSEGV, Segmentation fault.
> > > > > > > >> > queue_remove (queue=3D0x30, data=3Ddata@entry=3D0x555555=
873740) at
> > > > > > > >> > bluez/repo/src/shared/queue.c:256
> > > > > > > >> > 256 for (entry =3D queue->head, prev =3D NULL; entry;
> > > > > > > >> > (gdb) bt
> > > > > > > >> > #0  queue_remove (queue=3D0x30, data=3Ddata@entry=3D0x55=
5555873740) at
> > > > > > > >> > bluez/repo/src/shared/queue.c:256
> > > > > > > >> > #1  0x00005555555ab8c5 in att_disconnected (err=3D<optim=
ized out>,
> > > > > > > >> > user_data=3D0x555555873740)
> > > > > > > >> >     at bluez/repo/src/gatt-database.c:350
> > > > > > > >> > #2  0x00005555555eabb8 in queue_foreach (queue=3D0x55555=
586e670,
> > > > > > > >> > function=3Dfunction@entry=3D0x5555555ee600 <disconn_hand=
ler>,
> > > > > > > >> > user_data=3D0x68)
> > > > > > > >> >     at bluez/repo/src/shared/queue.c:220
> > > > > > > >> > #3  0x00005555555ef829 in disconnect_cb (io=3D<optimized=
 out>,
> > > > > > > >> > user_data=3D0x555555865f50)
> > > > > > > >> >     at bluez/repo/src/shared/att.c:592
> > > > > > > >> > #4  0x00005555555f89b3 in watch_callback (channel=3D<opt=
imized out>,
> > > > > > > >> > cond=3D<optimized out>, user_data=3D<optimized out>)
> > > > > > > >> >     at bluez/repo/src/shared/io-glib.c:170
> > > > > > > >> > #5  0x00007ffff7b0fe35 in g_main_context_dispatch () fro=
m
> > > > > > > >> > /lib/x86_64-linux-gnu/libglib-2.0.so.0
> > > > > > > >> > #6  0x00007ffff7b10200 in ?? () from /lib/x86_64-linux-g=
nu/libglib-2.0.so.0
> > > > > > > >> > #7  0x00007ffff7b10512 in g_main_loop_run () from
> > > > > > > >> > /lib/x86_64-linux-gnu/libglib-2.0.so.0
> > > > > > > >> > #8  0x0000555555572238 in main (argc=3D<optimized out>, =
argv=3D<optimized
> > > > > > > >> > out>) at  bluez/repo/src/main.c:808
> > > > > > > >> > On Thu, Oct 25, 2018 at 2:20 AM Luiz Augusto von Dentz
> > > > > > > >> > <luiz.dentz@gmail.com> wrote:
> > > > > > > >> > >
> > > > > > > >> > > Hi Yunhan,
> > > > > > > >> > >
> > > > > > > >> > > On Thu, Oct 25, 2018 at 4:47 AM Yunhan Wang <yunhanw@g=
oogle.com> wrote:
> > > > > > > >> > > >
> > > > > > > >> > > > Hi, Luiz
> > > > > > > >> > > >
> > > > > > > >> > > > I am observing the multiple crashes when doing BLE d=
isconnection using
> > > > > > > >> > > > latest bluez master..It looks like the two att_disco=
nnect are
> > > > > > > >> > > > triggered from your last gatt commit.. Please help t=
ake a look at this
> > > > > > > >> > > > workaround and comments.. the better solution might =
be to figure out
> > > > > > > >> > > > how to handle the disconnection along with random ad=
dress and public
> > > > > > > >> > > > address together regarding the previous issue, Gatt:=
 Subscriptions are
> > > > > > > >> > > > not cleared after disconnection from a temporary dev=
ice
> > > > > > > >> > >
> > > > > > > >> > > Ive pushed a similar fix, it should remove the handler=
 before calling
> > > > > > > >> > > att_disconnected.
> > > > > > > >> > >
> > > > > > > >> > > > Thanks
> > > > > > > >> > > > Best wishes
> > > > > > > >> > > > Yunhan
> > > > > > > >> > > > On Wed, Oct 24, 2018 at 5:42 PM yunhanw <yunhanw@goo=
gle.com> wrote:
> > > > > > > >> > > > >
> > > > > > > >> > > > > When BLE disconnection happens, att_disconnect is =
triggered from two locations, the new added location is gatt_server_cleanup=
, it would cause several blueetoothd crashes. This bus is introduced from c=
ommit 634f0a6e1125af8d5959bff119d9336a8d81c028, where gatt fix, gatt subscr=
iptions are not cleared after disconnection from a temporary device with pr=
ivate/random address. In order to workaround this issue, btd_gatt_database_=
att_disconnected can only be triggered when address type is random, and for=
 others, it can continue to use original disconnect code path.
> > > > > > > >> > > > >
> > > > > > > >> > > > >     crash 1
> > > > > > > >> > > > >     Program received signal SIGSEGV, Segmentation =
fault.
> > > > > > > >> > > > >     queue_remove (queue=3D0x30, data=3Ddata@entry=
=3D0x555555872a40) at /repo/src/shared/queue.c:256
> > > > > > > >> > > > >     256     for (entry =3D queue->head, prev =3D N=
ULL; entry;
> > > > > > > >> > > > >     (gdb) backtrace
> > > > > > > >> > > > >         at /bluez/repo/src/gatt-database.c:350
> > > > > > > >> > > > >         at bluez/repo/src/shared/queue.c:220
> > > > > > > >> > > > >         at bluez/repo/src/shared/att.c:592
> > > > > > > >> > > > >         at bluez/repo/src/shared/io-glib.c:170
> > > > > > > >> > > > >
> > > > > > > >> > > > >     crash 2
> > > > > > > >> > > > >         at bluez/repo/src/shared/queue.c:220
> > > > > > > >> > > > >         at bluez/repo/src/shared/att.c:592
> > > > > > > >> > > > >         at bluez/repo/src/shared/io-glib.c:170
> > > > > > > >> > > > >
> > > > > > > >> > > > >     (gdb) print state->db->adapter
> > > > > > > >> > > > >     Cannot access memory at address 0x61672f626972=
7474
> > > > > > > >> > > > > ---
> > > > > > > >> > > > >  src/gatt-database.c | 2 ++
> > > > > > > >> > > > >  1 file changed, 2 insertions(+)
> > > > > > > >> > > > >
> > > > > > > >> > > > > diff --git a/src/gatt-database.c b/src/gatt-databa=
se.c
> > > > > > > >> > > > > index 783b692d5..2f0eb83b5 100644
> > > > > > > >> > > > > --- a/src/gatt-database.c
> > > > > > > >> > > > > +++ b/src/gatt-database.c
> > > > > > > >> > > > > @@ -3365,6 +3365,8 @@ void btd_gatt_database_att_d=
isconnected(struct btd_gatt_database *database,
> > > > > > > >> > > > >
> > > > > > > >> > > > >         addr =3D device_get_address(device);
> > > > > > > >> > > > >         type =3D btd_device_get_bdaddr_type(device=
);
> > > > > > > >> > > > > +    if (type !=3D BDADDR_LE_RANDOM)
> > > > > > > >> > > > > +        return;
> > > > > > > >> > > > >
> > > > > > > >> > > > >         state =3D find_device_state(database, addr=
, type);
> > > > > > > >> > > > >         if (!state)
> > > > > > > >> > > > > --
> > > > > > > >> > > > > 2.19.1.568.g152ad8e336-goog
> > > > > > > >> > > > >
> > > > > > > >> > >
> > > > > > > >> > >
> > > > > > > >> > >
> > > > > > > >> > > --
> > > > > > > >> > > Luiz Augusto von Dentz
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > > --
> > > > > > > Luiz Augusto von Dentz
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > > Luiz Augusto von Dentz
> > >
> > >
> > >
> > > --
> > > Luiz Augusto von Dentz


--=20
Luiz Augusto von Dentz