Hi, Jaak, On Thu, Oct 26, 2023 at 2:49 AM Jaak Ristioja <jaak@xxxxxxxxxxx> wrote: > > On 25.10.23 16:23, Huacai Chen wrote: > > On Wed, Oct 25, 2023 at 6:08 PM Thorsten Leemhuis > > <regressions@xxxxxxxxxxxxx> wrote: > >> > >> Javier, Dave, Sima, > >> > >> On 23.10.23 00:54, Evan Preston wrote: > >>> 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"). > >>>>>>>>>> > >>>>>>>> As confirmed by Jaak, disabling DRM_SIMPLEDRM makes things work fine > >>>>>>>> again. So I guess the reason: > >>>>> > >>>>> 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. > >> > >> Side note: Huacai, have you tried working with Jaak to get down to the > >> real problem? Evan, might you be able to help out here? > > No, Jaak has no response after he 'fixed' his problem by disabling SIMPLEDRM. > > > > I'm sorry, what was it exactly you want me to do? Please be mindful that > I'm not familiar with the internals of the Linux kernel and DRI, and it > might sometimes take weeks before I have time to work and respond on this. It doesn't matter. I hope you can do some experiments to investigate deeper. The first experiment you can do is enabling SIMPLEFB (i.e. CONFIG_FB_SIMPLE) instead of SIMPLEDRM (CONFIG_DRM_SIMPLEDRM) to see whether there is also a blank screen. If no blank screen, that probably means SIMPLEDRM has a bug, if still blank screen, that means the firmware may pass wrong screen information. Huacai > > Jaak > > >> > >> But I write this mail for a different reason: > >> > >>> 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. > >> > >> This additional report makes me wonder if we should revert the culprit > >> (60aebc9559492c ("drivers/firmware: Move sysfb_init() from > >> device_initcall to subsys_initcall_sync") [v6.5-rc1]). But I guess that > >> might lead to regressions for some users? But the patch description says > >> that this is not a common configuration, so can we maybe get away with that? > > From my point of view, this is not a regression, 60aebc9559492c > > doesn't cause a problem, but exposes a problem. So we need to fix the > > real problem (SIMPLEDRM has a blank screen on some conditions). This > > needs Jaak or Evan's help. > > > > Huacai > >> > >> 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. > >> > >>>>>>>> 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 > >>>>>> > >>>>>> > >>> > >>> >