[REGRESSION] 4.18-rc2: X61s thinkpad display unusable after xlock & lid close

[Vito Caputo]

On Wed, Jun 27, 2018 at 05:18:39PM +0300, Ville Syrjälä wrote:
> On Tue, Jun 26, 2018 at 05:05:48PM -0700, Vito Caputo wrote:
> > Hello,
> > 
> > Beginning with 4.18, when I lock my X server using the `xlock` command,
> > and close the lid, upon reopening the lid I am not presented with the
> > xlock UI.
> > 
> > The system is not hung.  If I blindly enter the password, I get an
> > intact and functional pointer but none of the desktop is displayed.  I
> > can move the pointer, and cycling window focus generates some random
> > noise occasionally, but it's all nonsensical.  No windows are
> > discernable, it's just blackness with ephemeral noise on window cycles,
> > and a movable pointer.
> > 
> > The system does not suspend on lid close, with "HandleLidSwitch=ignore"
> > in logind.conf.  So this is a bit odd, since I don't observe this when I
> > just run `xlock` but don't close/open the lid before unlocking.
> > 
> > This is on Debian 9.4 amd64, the hardware is a 1.8Ghz X61s ThinkPad,
> > kernel config attached.  I'm using the modesetting Xorg driver on i915
> > KMS.
> 
> Ah, a Thinkpad with lid notifier. Now were getting somewhere :)
> 
> Can you pls test the stuff I listed here
> https://bugs.freedesktop.org/show_bug.cgi?id=105902#c5 ?
> 

Cherry-picking 8860e829faad on top of v4.18-rc2 seems to have fixed the
problem here.

Unfortunately I'm short on time currently to perform a bisect in the
interests of identifying the lid notification-breaking commit between
4.17 and 4.18.

Thanks,
Vito Caputo