Re: [REGRESSION] Bluetooth is not working on Macs with BCM4377 chip starting from kernel 6.5

From: Aditya Garg
Date: Tue Nov 14 2023 - 03:18:25 EST




> On 14-Nov-2023, at 1:28 PM, Hector Martin <marcan@xxxxxxxxx> wrote:
>
> On 14/11/2023 15.59, Hector Martin wrote:
>> On 14/11/2023 15.23, Aditya Garg wrote:
>>>
>>>
>>>> On 14-Nov-2023, at 5:01 AM, Bagas Sanjaya <bagasdotme@xxxxxxxxx> wrote:
>>>>
>>>> On Mon, Nov 13, 2023 at 08:57:35PM +0000, Aditya Garg wrote:
>>>>> Starting from kernel 6.5, a regression in the kernel is causing Bluetooth to not work on T2 Macs with BCM4377 chip.
>>>>>
>>>>> Journalctl of kernel 6.4.8 which has Bluetooth working is given here: https://pastebin.com/u9U3kbFJ
>>>>>
>>>>> Journalctl of kernel 6.5.2, which has Bluetooth broken is given here: https://pastebin.com/aVHNFMRs
>>>>>
>>>>> Also, the bug hasn’t been fixed even in 6.6.1, as reported by users.
>>>>
>>>> Can you bisect this regression please?
>>>
>>> Since I don't have access to this hardware, it's not possible for me to bisect this regression. Let's hope someone is able to do so though.
>>
>> It's not a regression, it was always broken. I'm sending a patch.
>>
>> - Hector
>
> You are quite likely conflating two problems. The ubsan issue you quoted
> was always there and the patch I just sent fixes it, but it almost
> certainly always worked fine in practice without ubsan.
>
> The Bluetooth problem you are referring to is likely *specific to
> Bluetooth LE devices* and the regression was introduced by 288c90224e
> and fixed by 41e9cdea9c, which is also in 6.5.11 and 6.6.1.
>
> If Bluetooth is broken in *some other way* in 6.6.1 then we need a
> proper report or a bisect. Your logs don't show any issues other than
> the ubsan noise, which is not a regression.
>
> - Hector
I’ll request users with the hardware to test the patch you sent. Talking about
LE devices, I guess I can go ahead testing with the quirk if your patch doesn't
Work.
>