Re: Lenovo ThinkPad X13s regerssions (was Re: Linux regressions report for mainline [2024-02-25])

[Johan Hovold <johan@kernel.org>]

[ +CC: Vinod, Bjorn, Abhinav ]

On Tue, Mar 05, 2024 at 10:33:39AM +0100, Linux regression tracking (Thorsten Leemhuis) wrote:
> [dropping Linus from CC, we can add him back later when needed]
> 
> On 27.02.24 11:20, Johan Hovold wrote:
> > On Sun, Feb 25, 2024 at 01:21:46PM +0000, Regzbot (on behalf of Thorsten Leemhuis) wrote:
> > 
> >> Johan Hovold also deals with multiple issues affecting Lenovo ThinkPad
> >> X13s, but he send out patch series to fix some or all of those[1], so
> >> with a bit of luck those issues will soon be fixed as well.
> >> https://lore.kernel.org/lkml/ZctVmLK4zTwcpW3A@hovoldconsulting.com/
> 
> As 6.8 final might be just five days away, could you please help me out
> with a short status update wrt. unresolved regressions from your side if
> you have a minute? It's easy to get lost in all those issues. :-/ :-D

Heh. Indeed. It's been a rough cycle. :)

> >> [1]
> >> https://lore.kernel.org/lkml/20240217150228.5788-1-johan+linaro@kernel.org/
> > 
> > This series addresses a use-after-free in the PMIC glink driver caused
> > by DRM bridge changes in rc1 and which can result in the internal
> > display not showing up on boot.
> > 
> > The DRM/SoC fixes here have now been merged to drm-misc for 6.8.
> 
> What about the others from that series? Can they wait till 6.9? Or are
> they on track for 6.8?

Vinod, the PHY maintainer, just told me he will try to get them into
6.8.

> > But also with these fixes, there are still a couple of regressions
> > related to the Qualcomm DRM runtime PM rework in 6.8-rc1. I'll send
> > separate reports to track those.
> 
> Any decision yet if they are going to be reverted for now?
>
> Am I right assuming those would fix
> https://lore.kernel.org/lkml/Zd3kvD02Qvsh2Sid@hovoldconsulting.com/
> which did not get even a single reply?

That was the hope, but I've managed to trigger a reset on disconnect
once also with the runtime PM series reverted.

One of the patches from that series has already been reverted (to fix
the VT console hotplug regression) and there is some indication that
that was sufficient to address the issue with hotplug not being detected
in X/Wayland too. I'm waiting for confirmation from some users that have
not been able to use their external displays at all since 6.8-rc1, but
it does seem to fix the X/Wayland issues I could reproduce here.

But either way, the reset on disconnect is still there, and have since
been reproduced by Bjorn also on another Qualcomm platform without a
hypervisor so that we've now got a call stack. I've heard that Abhinav
is looking into that, but I don't know if there's any chance to have a
fix ready this week.

Johan