i915 IVB hangup after resume from s2mem since v6.6.x

[Lukas Wunner]

[cc += Thomas]

On Mon, May 06, 2024 at 08:43:43PM +0200, Johannes Stezenbach wrote:
> so, git bisect pointed to:
> 
>  commit 701d2054fa317188cd4039c84e72c73254013b23
>  Author: Thomas Zimmermann <tzimmermann at suse.de>
>  Date:   Tue Jun 13 13:07:13 2023 +0200
> 
>     fbdev: Make support for userspace interfaces configurable
> 
>     Add Kconfig option CONFIG_FB_DEVICE and make the virtual fbdev
>     ...
> 
> I think nothing on my system uses /dev/fb*, thus I had disabled
> CONFIG_FB_DEVICE. Everything worked, only suspend/resume broke.
> I can confirm v6.8.9 with CONFIG_FB_DEVICE=y works fine.
> 
> Maybe setting CONFIG_FB_DEVICE=n would allow you to reproduce
> it in your CI tests?
> Let me know if you still want me to file at bug report about this.

A user-visible regression like this is always sufficient to ask for a
revert of the offending commit.  It's the commit author's duty to find
a fix ASAP. If you could file a bug report that would be helpful but
you've already done more than could be asked from any user.

Thanks,

Lukas