Re: [PATCH v1 2/2] HID: logitech-hidpp: Add Bluetooth Mouse M336/M337/M535 to unhandled_hidpp_devices[]

[Rafael J. Wysocki]

On Wed, Dec 7, 2022 at 2:25 PM Benjamin Tissoires
<benjamin.tissoires@xxxxxxxxxx> wrote:
>
> On Wed, Dec 7, 2022 at 2:01 PM Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
> >
> > On Wed, Dec 7, 2022 at 1:43 PM Bastien Nocera <hadess@xxxxxxxxxx> wrote:
> > >
> > > On Wed, 2022-12-07 at 11:19 +0100, Jiri Kosina wrote:
> > > > On Wed, 7 Dec 2022, Benjamin Tissoires wrote:
> > > >
> > > > > Agree, but OTOH, Rafael, your mouse is not brand new AFAICT, so I
> > > > > am
> > > > > worried that you won't be the only one complaining we just killed
> > > > > their
> > > > > mouse. So I think the even wiser solution would be to delay (and so
> > > > > revert in 6.1 or 6.2) the 2 patches that enable hid++ on all
> > > > > logitech
> > > > > mice (8544c812e43ab7bdf40458411b83987b8cba924d and
> > > > > 532223c8ac57605a10e46dc0ab23dcf01c9acb43).
> > > >
> > > > If we were not at -rc8 timeframe, I'd be in favor to coming up with
> > > > proper
> > > > fix still for 6.1. But as things currently are, let's just revert
> > > > those
> > > > and reschedule them with proper fix for 6.2+.
> > >
> > > Has anyone seen any other reports?
>
> It's not so much about how many reports, but *what* the end result is.
> If the device were working-ish, that would have been OK. But here the
> device is completely ignored by the kernel which basically enters the
> "no regression rule".
>
> > >
> > > Because, honestly, seeing work that adds support for dozens of devices
> > > getting tossed out at the last minute based on a single report with no
> > > opportunity to fix the problem is really frustrating.
>
> I know, and I feel your pain as I was about to have the same last week
> for HID-BPF. But as much as I hate dropping patches from the queue,
> not being able to have at least a week to fix it properly ends up with
> "fixes" that are broken and that might break other devices. Talking
> from experience as my first fix from last week was exactly in that
> category.
>
> >
> > Well, that's why I sent patches to address this particular case
> > without possibly breaking anything else.
>
> My concern is more that we now have a data point were the series broke
> a device (pretty badly) and if (when) this happens shortly after 6.1
> is getting released, we would have to say, oh yes, we know, so we need
> to patch the kernel because our driver is buggy, and we knew it. This
> is not acceptable, and I am sure that if Linus reads that thread he
> would revert the 2 patches or maybe more.

Well, I agree.

> >
> > Improvements can be made on top of them and the blocklist entry added
> > by patch [2/2] need not stay there forever, FWIW.
> >
>
> I need to check with Jiri, but there is a chance we can re-introduce
> this in 6.2. This way we will have slightly more time to fix it in a
> proper way.

Sounds good to me.