Re: Blank screen on boot of Linux 6.5 and later on Lenovo ThinkPad L570

[Evan Preston]

On 2023-10-20 Fri 05:48pm, Huacai Chen wrote:
> On Fri, Oct 20, 2023 at 5:35 PM Linux regression tracking (Thorsten
> Leemhuis) <regressions@xxxxxxxxxxxxx> wrote:
> >
> > On 09.10.23 10:54, Huacai Chen wrote:
> > > On Mon, Oct 9, 2023 at 4:45 PM Bagas Sanjaya <bagasdotme@xxxxxxxxx> wrote:
> > >> On Mon, Oct 09, 2023 at 09:27:02AM +0800, Huacai Chen wrote:
> > >>> On Tue, Sep 26, 2023 at 10:31 PM Huacai Chen <chenhuacai@xxxxxxxxxx> wrote:
> > >>>> On Tue, Sep 26, 2023 at 7:15 PM Linux regression tracking (Thorsten
> > >>>> Leemhuis) <regressions@xxxxxxxxxxxxx> wrote:
> > >>>>> On 13.09.23 14:02, Jaak Ristioja wrote:
> > >>>>>>
> > >>>>>> Upgrading to Linux 6.5 on a Lenovo ThinkPad L570 (Integrated Intel HD
> > >>>>>> Graphics 620 (rev 02), Intel(R) Core(TM) i7-7500U) results in a blank
> > >>>>>> screen after boot until the display manager starts... if it does start
> > >>>>>> at all. Using the nomodeset kernel parameter seems to be a workaround.
> > >>>>>>
> > >>>>>> I've bisected this to commit 60aebc9559492cea6a9625f514a8041717e3a2e4
> > >>>>>> ("drivers/firmware: Move sysfb_init() from device_initcall to
> > >>>>>> subsys_initcall_sync").
> > >>>>>
> > >>>>> Hmmm, no reaction since it was posted a while ago, unless I'm missing
> > >>>>> something.
> > >>>>>
> > >>>>> Huacai Chen, did you maybe miss this report? The problem is apparently
> > >>>>> caused by a commit of yours (that Javier applied), you hence should look
> > >>>>> into this.
> > >>>> I'm sorry but it looks very strange, could you please share your config file?
> > >>> As confirmed by Jaak, disabling DRM_SIMPLEDRM makes things work fine
> > >>> again. So I guess the reason:
> > >>
> > >> Did Jaak reply privately? It should have been disclosed in public
> > >> ML here instead.
> > > Yes, he replied privately, and disabling DRM_SIMPLEDRM was suggested by me.
> >
> > Well, this to me still looks a lot (please correct me if I'm wrong) like
> > regression that should be fixed, as DRM_SIMPLEDRM was enabled beforehand
> > if I understood things correctly. Or is there a proper fix for this
> > already in the works and I just missed this? Or is there some good
> > reason why this won't/can't be fixed?
> DRM_SIMPLEDRM was enabled but it didn't work at all because there was
> no corresponding platform device. Now DRM_SIMPLEDRM works but it has a
> blank screen. Of course it is valuable to investigate further about
> DRM_SIMPLEDRM on Jaak's machine, but that needs Jaak's effort because
> I don't have a same machine.
> 
> Huacai

I am having the same issue on a Lenovo Thinkpad P70 (Intel Corporation HD Graphics 530 (rev 06), Intel(R) Core(TM) i7-6700HQ).  Upgrading from Linux 6.4.12 to 6.5 and later results in only a blank screen after boot and a rapidly flashing device-access-status indicator.

> >
> > Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
> > --
> > Everything you wanna know about Linux kernel regression tracking:
> > https://linux-regtracking.leemhuis.info/about/#tldr
> > If I did something stupid, please tell me, as explained on that page.
> >
> > #regzbot poke
> >
> > >>> When SIMPLEDRM takes over the framebuffer, the screen is blank (don't
> > >>> know why). And before 60aebc9559492cea6a9625f ("drivers/firmware: Move
> > >>> sysfb_init() from device_initcall to subsys_initcall_sync") there is
> > >>> no platform device created for SIMPLEDRM at early stage, so it seems
> > >>> also "no problem".
> > >>
> > >> I don't understand above. You mean that after that commit the platform
> > >> device is also none, right?
> > > No. The SIMPLEDRM driver needs a platform device to work, and that
> > > commit makes the platform device created earlier. So, before that
> > > commit, SIMPLEDRM doesn't work, but the screen isn't blank; after that
> > > commit, SIMPLEDRM works, but the screen is blank.
> > >
> > > Huacai
> > >>
> > >> Confused...
> > >>
> > >> --
> > >> An old man doll... just what I always wanted! - Clara
> > >
> > >