Re: [PATCH 1/2] Revert "xhci: Enable RPM on controllers that support low-power states"

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Dec 04, 2023 at 08:59:35PM +0530, Basavaraj Natikar wrote:
> 
> On 12/4/2023 8:36 PM, Mathias Nyman wrote:
> > On 4.12.2023 16.49, Basavaraj Natikar wrote:
> >>
> >> On 12/4/2023 7:52 PM, Mathias Nyman wrote:
> >>> On 4.12.2023 12.49, Basavaraj Natikar wrote:
> >>>>
> >>>> On 12/4/2023 3:38 PM, Mathias Nyman wrote:
> >>>>> This reverts commit a5d6264b638efeca35eff72177fd28d149e0764b.
> >>>>>
> >>>>> This patch was an attempt to solve issues seen when enabling
> >>>>> runtime PM
> >>>>> as default for all AMD 1.1 xHC hosts. see commit 4baf12181509
> >>>>> ("xhci: Loosen RPM as default policy to cover for AMD xHC 1.1")
> >>>>
> >>>> AFAK, only 4baf12181509 commit has regression on AMD xHc 1.1 below is
> >>>> not regression
> >>>> patch and its unrelated to AMD xHC 1.1.
> >>>>
> >>>> Only [PATCH 2/2] Revert "xhci: Loosen RPM as default policy to cover
> >>>> for AMD xHC 1.1"
> >>>> alone in this series solves regression issues.
> >>>>
> >>>
> >>> Patch a5d6264b638e ("xhci: Enable RPM on controllers that support
> >>> low-power states")
> >>> was originally not supposed to go to stable. It was added later as it
> >>> solved some
> >>> cases triggered by 4baf12181509 ("xhci: Loosen RPM as default policy
> >>> to cover for AMD xHC 1.1")
> >>> see:
> >>> https://lore.kernel.org/linux-usb/5993222.lOV4Wx5bFT@natalenko.name/
> >>>
> >>> Turns out it wasn't enough.
> >>>
> >>> If we now revert 4baf12181509 "xhci: Loosen RPM as default policy to
> >>> cover for AMD xHC 1.1"
> >>> I still think it makes sense to also revert a5d6264b638e.
> >>> Especially from the stable kernels.
> >>
> >> Yes , a5d6264b638e still solves other issues if underlying hardware
> >> doesn't support RPM
> >> if we revert a5d6264b638e on stable releases then new issues (not
> >> related to regression)
> >> other than AMD xHC 1.1 controllers including xHC 1.2 will still exist
> >> on stable releases.
> >
> > Ok, got it, so a5d6264b638e also solves other issues than those
> > exposed by 4baf12181509.
> > And that one (a5d6264b638) should originally have been marked for stable.
> >
> > So only revert 4baf12181509, PATCH 2/2 in this series
> 
> Thank you, that is correct.

So just take patch 2/2 here, or will someone be sending me a new patch?

thanks,

greg k-h