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

Bluetooth: Send HCI Set Event Mask Page 2 command only when needed

to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: bluetooth-send-hci-set-event-mask-page-2-command-only-when-needed.patch and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Mon Apr 9 17:09:24 CEST 2018

From: Marcel Holtmann marcel@holtmann.org Date: Fri, 9 Jun 2017 18:43:56 +0200 Subject: Bluetooth: Send HCI Set Event Mask Page 2 command only when needed

From: Marcel Holtmann marcel@holtmann.org

[ Upstream commit 313f6888c8fbb1bc8b36c9012ce4e1de848df696 ]

The Broadcom BCM20702 Bluetooth controller in ThinkPad-T530 devices report support for the Set Event Mask Page 2 command, but actually do return an error when trying to use it.

< HCI Command: Read Local Supported Commands (0x04|0x0002) plen 0

HCI Event: Command Complete (0x0e) plen 68

Read Local Supported Commands (0x04|0x0002) ncmd 1 Status: Success (0x00) Commands: 162 entries ... Set Event Mask Page 2 (Octet 22 - Bit 2) ...

< HCI Command: Set Event Mask Page 2 (0x03|0x0063) plen 8 Mask: 0x0000000000000000

HCI Event: Command Complete (0x0e) plen 4

Set Event Mask Page 2 (0x03|0x0063) ncmd 1 Status: Unknown HCI Command (0x01)

Since these controllers do not support any feature that would require the event mask page 2 to be modified, it is safe to not send this command at all. The default value is all bits set to zero.

T: Bus=01 Lev=02 Prnt=02 Port=03 Cnt=03 Dev#= 9 Spd=12 MxCh= 0 D: Ver= 2.00 Cls=ff(vend.) Sub=01 Prot=01 MxPS=64 #Cfgs= 1 P: Vendor=0a5c ProdID=21e6 Rev= 1.12 S: Manufacturer=Broadcom Corp S: Product=BCM20702A0 S: SerialNumber=F82FA8E8CFC0 C:* #Ifs= 4 Cfg#= 1 Atr=e0 MxPwr= 0mA I:* If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb E: Ad=81(I) Atr=03(Int.) MxPS= 16 Ivl=1ms E: Ad=82(I) Atr=02(Bulk) MxPS= 64 Ivl=0ms E: Ad=02(O) Atr=02(Bulk) MxPS= 64 Ivl=0ms I:* If#= 1 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 0 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 0 Ivl=1ms I: If#= 1 Alt= 1 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 9 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 9 Ivl=1ms I: If#= 1 Alt= 2 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 17 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 17 Ivl=1ms I: If#= 1 Alt= 3 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 25 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 25 Ivl=1ms I: If#= 1 Alt= 4 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 33 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 33 Ivl=1ms I: If#= 1 Alt= 5 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 49 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 49 Ivl=1ms I:* If#= 2 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=btusb E: Ad=84(I) Atr=02(Bulk) MxPS= 32 Ivl=0ms E: Ad=04(O) Atr=02(Bulk) MxPS= 32 Ivl=0ms I:* If#= 3 Alt= 0 #EPs= 0 Cls=fe(app. ) Sub=01 Prot=01 Driver=(none)

Signed-off-by: Marcel Holtmann marcel@holtmann.org Reported-by: Sedat Dilek sedat.dilek@gmail.com Tested-by: Sedat Dilek sedat.dilek@gmail.com Signed-off-by: Szymon Janc szymon.janc@codecoup.pl Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/bluetooth/hci_core.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-)

--- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -548,6 +548,7 @@ static void hci_set_event_mask_page_2(st { struct hci_dev *hdev = req->hdev; u8 events[8] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; + bool changed = false;

/* If Connectionless Slave Broadcast master role is supported * enable all necessary events for it. @@ -557,6 +558,7 @@ static void hci_set_event_mask_page_2(st events[1] |= 0x80; /* Synchronization Train Complete */ events[2] |= 0x10; /* Slave Page Response Timeout */ events[2] |= 0x20; /* CSB Channel Map Change */ + changed = true; }

/* If Connectionless Slave Broadcast slave role is supported @@ -567,13 +569,24 @@ static void hci_set_event_mask_page_2(st events[2] |= 0x02; /* CSB Receive */ events[2] |= 0x04; /* CSB Timeout */ events[2] |= 0x08; /* Truncated Page Complete */ + changed = true; }

/* Enable Authenticated Payload Timeout Expired event if supported */ - if (lmp_ping_capable(hdev) || hdev->le_features[0] & HCI_LE_PING) + if (lmp_ping_capable(hdev) || hdev->le_features[0] & HCI_LE_PING) { events[2] |= 0x80; + changed = true; + }

- hci_req_add(req, HCI_OP_SET_EVENT_MASK_PAGE_2, sizeof(events), events); + /* Some Broadcom based controllers indicate support for Set Event + * Mask Page 2 command, but then actually do not support it. Since + * the default value is all bits set to zero, the command is only + * required if the event mask has to be changed. In case no change + * to the event mask is needed, skip this command. + */ + if (changed) + hci_req_add(req, HCI_OP_SET_EVENT_MASK_PAGE_2, + sizeof(events), events); }

static int hci_init3_req(struct hci_request *req, unsigned long opt)

Patches currently in stable-queue which might be from marcel@holtmann.org are

queue-4.9/bluetooth-send-hci-set-event-mask-page-2-command-only-when-needed.patch queue-4.9/net-ieee802154-fix-net_device-reference-release-too-early.patch