Re: [PATCH] HID: logitech-hidpp: Handle timeout differently from busy

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Tue, Jun 06, 2023 at 08:37:26PM +0200, Benjamin Tissoires wrote:
> On Tue, Jun 6, 2023 at 8:18 PM Linux regression tracking (Thorsten
> Leemhuis) <regressions@leemhuis.info> wrote:
> >
> >
> >
> > On 06.06.23 15:27, Jiri Kosina wrote:
> > > On Mon, 5 Jun 2023, Linux regression tracking (Thorsten Leemhuis) wrote:
> > >
> > >>>>> If an attempt at contacting a receiver or a device fails because the
> > >>>>> receiver or device never responds, don't restart the communication, only
> > >>>>> restart it if the receiver or device answers that it's busy, as originally
> > >>>>> intended.
> > >>>>>
> > >>>>> This was the behaviour on communication timeout before commit 586e8fede795
> > >>>>> ("HID: logitech-hidpp: Retry commands when device is busy").
> > >>>>>
> > >>>>> This fixes some overly long waits in a critical path on boot, when
> > >>>>> checking whether the device is connected by getting its HID++ version.
> > >>>>>
> > >>>>> Signed-off-by: Bastien Nocera <hadess@hadess.net>
> > >>>>> Suggested-by: Mark Lord <mlord@pobox.com>
> > >>>>> Fixes: 586e8fede795 ("HID: logitech-hidpp: Retry commands when device is busy")
> > >>>>> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217412
> > >>> [...]
> > >>>>
> > >>>> I have applied this even before getting confirmation from the reporters in
> > >>>> bugzilla, as it's the right thing to do anyway.
> > >>>
> > >>> Unfortunately it doesn't seem to cure the reported issue (while reverting
> > >>> 586e8fede79 does):
> > >>
> > >> BTW, remind me again: was fixing this by reverting 586e8fede79 for now a
> > >> option? I guess it's not, but if I'm wrong I wonder if that might at
> > >> this point be the best way forward.
> > >
> > > This should now all be fixed by
> > >
> > >     https://git.kernel.org/linus/7c28afd5512e371773dbb2bf95a31ed5625651d9
> >
> > Jiri, Benjamin, many many thx for working on this.
> >
> > Hmmm. No CC: <stable... tag.
> >
> > Should we ask Greg to pick this up for 6.3 now, or better wait a few
> > days? He currently already has 6199d23c91ce ("HID: logitech-hidpp:
> > Handle timeout differently from busy") in his queue for the next 6.3.y
> > release.
> 
> Well, the Fixes: tag supposedly is enough to let the stable folks to
> pick it up.

No, not at all, please see:
    https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

(hint, we need a cc: stable@ in the signed-off-by area.)

We only pick up stuff with "Fixes:" semi-often, sometimes never,
depending on our workload.  Never rely on that.

It's been this way for 18+ years now, nothing new :)

> But you are right, let's Cc Greg for a quicker inclusion
> in the 6.3 tree.
> 
> Greg, would you mind adding the commit above (7c28afd5512e37) onto the
> 6.3 stable queue? Thanks!

Now queued up, thanks.

greg k-h