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Sun, 05 Nov 2023 18:15:52 -0800 (PST) X-Gm-Message-State: AOJu0Yzzt4WftcyZopxjat869MuUXfitCp6MfjPTAYvDVTtdrua8ts+E WyQ8wDLgRaasnZgwrkjipLh8W0M7bPbcn276xWs= X-Received: by 2002:a17:907:84a:b0:9be:c2cd:aa29 with SMTP id ww10-20020a170907084a00b009bec2cdaa29mr10598664ejb.77.1699236951067; Sun, 05 Nov 2023 18:15:51 -0800 (PST) MIME-Version: 1.0 References: <31ed0db1-9398-4c46-a391-fc644ec49268@ristioja.ee> <51add74a-1d1a-493d-bb50-fccdad11b22c@ristioja.ee> In-Reply-To: <51add74a-1d1a-493d-bb50-fccdad11b22c@ristioja.ee> From: Huacai Chen Date: Mon, 6 Nov 2023 10:15:38 +0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: Blank screen on boot of Linux 6.5 and later on Lenovo ThinkPad L570 To: Jaak Ristioja Cc: Evan Preston , Linux regressions mailing list , Javier Martinez Canillas , Linux DRI Development , Linux Kernel Mailing List , Thorsten Leemhuis , Thomas Zimmermann , Bagas Sanjaya Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-1.8 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,T_PDS_OTHER_BAD_TLD,T_SCC_BODY_TEXT_LINE, WEIRD_PORT autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on agentk.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (agentk.vger.email [0.0.0.0]); Sun, 05 Nov 2023 18:16:13 -0800 (PST) Hi, Jaak and Evan, On Mon, Nov 6, 2023 at 12:28=E2=80=AFAM Jaak Ristioja wr= ote: > > On 05.11.23 14:40, Huacai Chen wrote: > > Hi, Evan, > > > > On Sat, Nov 4, 2023 at 10:50=E2=80=AFAM Evan Preston wrote: > >> > >> Hi Huacai, > >> > >> On 2023-11-03 Fri 02:36pm, Huacai Chen wrote: > >>> Hi, Evan, > >>> > >>> On Fri, Nov 3, 2023 at 1:54=E2=80=AFPM Evan Preston wrote: > >>>> > >>>> Hi Huacai, > >>>> > >>>> On 2023-11-02 Thu 08:38pm, Huacai Chen wrote: > >>>>> Hi, Jaak, > >>>>> > >>>>> On Wed, Nov 1, 2023 at 7:52=E2=80=AFPM Jaak Ristioja wrote: > >>>>>> > >>>>>> On 31.10.23 14:17, Huacai Chen wrote: > >>>>>>> Hi, Jaak and Evan, > >>>>>>> > >>>>>>> On Sun, Oct 29, 2023 at 9:42=E2=80=AFAM Huacai Chen wrote: > >>>>>>>> > >>>>>>>> On Sat, Oct 28, 2023 at 7:06=E2=80=AFPM Jaak Ristioja wrote: > >>>>>>>>> > >>>>>>>>> On 26.10.23 03:58, Huacai Chen wrote: > >>>>>>>>>> Hi, Jaak, > >>>>>>>>>> > >>>>>>>>>> On Thu, Oct 26, 2023 at 2:49=E2=80=AFAM Jaak Ristioja wrote: > >>>>>>>>>>> > >>>>>>>>>>> On 25.10.23 16:23, Huacai Chen wrote: > >>>>>>>>>>>> On Wed, Oct 25, 2023 at 6:08=E2=80=AFPM Thorsten Leemhuis > >>>>>>>>>>>> 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=E2=80=AFPM Linux regression = tracking (Thorsten > >>>>>>>>>>>>>>> Leemhuis) wrote: > >>>>>>>>>>>>>>>> On 09.10.23 10:54, Huacai Chen wrote: > >>>>>>>>>>>>>>>>> On Mon, Oct 9, 2023 at 4:45=E2=80=AFPM Bagas Sanjaya wrote: > >>>>>>>>>>>>>>>>>> On Mon, Oct 09, 2023 at 09:27:02AM +0800, Huacai Chen = wrote: > >>>>>>>>>>>>>>>>>>> On Tue, Sep 26, 2023 at 10:31=E2=80=AFPM Huacai Chen = wrote: > >>>>>>>>>>>>>>>>>>>> On Tue, Sep 26, 2023 at 7:15=E2=80=AFPM Linux regres= sion tracking (Thorsten > >>>>>>>>>>>>>>>>>>>> Leemhuis) 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 60aebc9559492cea6a962= 5f514a8041717e3a2e4 > >>>>>>>>>>>>>>>>>>>>>> ("drivers/firmware: Move sysfb_init() from device_= initcall to > >>>>>>>>>>>>>>>>>>>>>> subsys_initcall_sync"). > >>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> As confirmed by Jaak, disabling DRM_SIMPLEDRM makes t= hings 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 en= abled beforehand > >>>>>>>>>>>>>>>> if I understood things correctly. Or is there a proper f= ix 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 becau= se there was > >>>>>>>>>>>>>>> no corresponding platform device. Now DRM_SIMPLEDRM works= but it has a > >>>>>>>>>>>>>>> blank screen. Of course it is valuable to investigate fur= ther about > >>>>>>>>>>>>>>> DRM_SIMPLEDRM on Jaak's machine, but that needs Jaak's ef= fort 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 dis= abling SIMPLEDRM. > >>>>>>>>>>>> > >>>>>>>>>>> > >>>>>>>>>>> I'm sorry, what was it exactly you want me to do? Please be m= indful that > >>>>>>>>>>> I'm not familiar with the internals of the Linux kernel and D= RI, and it > >>>>>>>>>>> might sometimes take weeks before I have time to work and res= pond on this. > >>>>>>>>>> It doesn't matter. I hope you can do some experiments to inves= tigate > >>>>>>>>>> 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, tha= t means > >>>>>>>>>> the firmware may pass wrong screen information. > >>>>>>>>> > >>>>>>>>> Testing with 6.5.9 I get a blank screen with CONFIG_DRM_SIMPLED= RM=3Dy and > >>>>>>>>> get no blank screen with CONFIG_FB_SIMPLE=3Dy and CONFIG_DRM_SI= MPLEDRM unset. > >>>>>>>> CONFIG_FB_SIMPLE and CONFIG_DRM_SIMPLEDRM use the same device c= reated > >>>>>>>> by sysfb_init(). Since FB_SIMPLE works fine, I think the real pr= oblem > >>>>>>>> is that DRM_SIMPLEDRM has a bug. The next step is to enable > >>>>>>>> CONFIG_DRM_SIMPLEDRM and trace its initialization. In detail, ad= ding > >>>>>>>> some printk() in simpledrm_probe() and its sub-routines to see w= here > >>>>>>>> the driver fails. The output of these printk() can be seen by th= e > >>>>>>>> 'dmesg' command after boot. > >>>>>>> I need your help. I tried with my laptop (ThinkPad E490, Intel Co= re > >>>>>>> i3-8145U, UHD Graphics 620) but I can't reproduce your problem. S= o > >>>>>>> please patch your 6.5.x kernel with this temporary patch [1], the= n > >>>>>>> build a "bad kernel" with SIMPLEDRM enabled. And after booting yo= ur > >>>>>>> machine with this "bad kernel", please give me the dmesg output. = Thank > >>>>>>> you very much. > >>>>>>> > >>>>>>> [1] http://ddns.miaomiaomiao.top:9000/download/kernel/patch-6.5.9 > >>>>>> > >>>>>> I'm unable to download it. Can you please send it by e-mail? > >>>>> I'm sorry, please download from attachment. > >>>> > >>>> When applying this patch the first hunk (drivers/firmware/sysfb.c) f= ails for > >>>> me with 6.5.9. Attempting to load the 6.5.9 kernel without this pat= ch > >>>> produces no dmesg output on my machine. > >>> You copy-paste the patch? If you download it directly it can be > >>> applied successfully, I think. > >> > >> The patch downloaded from your URL applies successfully. However, I s= till > >> see no dmesg output using the patched 6.5.9 kernel. 'journalctl -k -b= all' > >> shows no dmesg output from any 6.5.x boots, only from 6.4.12 boots. > > Thank you for your testing. Since you cannot boot to GUI successfully > > as Jaak, you may have some troubles with getting the dmesg output. But > > you can try to use "systemd.unit=3Dmulti-user.target" boot parameters. > > In this way you may boot to the login: prompt and then you can get > > dmesg output. Or if you still fail, you may use 'jornalctl -k -b -1' > > to get the previous dmesg output with 6.4.12. > > > > Hi, Jaak, > > > > Have you tested? I think you can successfully get a dmesg output with m= y patch. > > Yes, just tested it, here I think are the relevant parts from a dmesg > produced with CONFIG_DRM_SIMPLEDRM and the patch provided by Huacai: > > ... > [ 2.909625] sysfb 1 > [ 2.909627] sysfb 2 > ... > [ 2.951477] ACPI: bus type drm_connector registered > [ 2.952096] i915 0000:00:02.0: [drm] VT-d active for gfx access > [ 2.952105] resource: resource sanity check: requesting [mem > 0x00000000e0000000-0x00000000efffffff], which spans more than BOOTFB > [mem 0xe0000000-0xe012bfff] > [ 2.952111] caller i915_ggtt_init_hw+0x88/0x120 mapping multiple BARs > [ 2.952138] i915 0000:00:02.0: [drm] Using Transparent Hugepages > [ 2.953204] Loading firmware: i915/kbl_dmc_ver1_04.bin > [ 2.953485] i915 0000:00:02.0: [drm] Finished loading DMC firmware > i915/kbl_dmc_ver1_04.bin (v1.4) > ... > [ 4.142075] [drm] Initialized i915 1.6.0 20201103 for 0000:00:02.0 on > minor 0 > [ 4.144269] ACPI: video: Video Device [GFX0] (multi-head: yes rom: > no post: no) > [ 4.144414] input: Video Bus as > /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/LNXVIDEO:00/input/input4 > [ 4.144580] [drm] Initialized vgem 1.0.0 20120112 for vgem on minor 1 > [ 4.144590] usbcore: registered new interface driver udl > [ 4.144603] T: probe 1 > [ 4.144605] T: create 1 > [ 4.144610] T: create 2 > [ 4.144611] T: create 3a-1 > [ 4.144613] T: create 3a-2 > [ 4.144614] T: create 3a-3 > [ 4.144616] T: create 3a-4 > [ 4.144618] T: create 4 > [ 4.144619] T: create 5 > [ 4.144621] simple-framebuffer simple-framebuffer.0: [drm] display > mode=3D{"": 60 18432 640 640 640 640 480 480 480 480 0x40 0x0} > [ 4.144628] simple-framebuffer simple-framebuffer.0: [drm] > framebuffer format=3DXR24 little-endian (0x34325258), size=3D640x480, > stride=3D2560 byte > [ 4.144633] T: create 6b-1 > [ 4.144635] T: create 6b-2 > [ 4.144637] simple-framebuffer simple-framebuffer.0: [drm] using I/O > memory framebuffer at [mem 0xe0000000-0xe012bfff flags 0x200] > [ 4.144643] T: create 6b-3 > [ 4.144660] T: create 6b-4 > [ 4.144662] T: create 7 > [ 4.144673] T: create 8 > [ 4.144676] T: create 9 > [ 4.144678] T: create 10 > [ 4.144681] T: create 11 > [ 4.144685] T: create 12 > [ 4.144689] T: probe 2 > [ 4.144728] [drm] Initialized simpledrm 1.0.0 20200625 for > simple-framebuffer.0 on minor 2 > [ 4.144732] T: probe 3 > [ 4.145905] Console: switching to colour frame buffer device 80x30 > [ 4.150437] simple-framebuffer simple-framebuffer.0: [drm] fb0: > simpledrmdrmfb frame buffer device > [ 4.150766] T: probe 4 > [ 4.151218] loop: module loaded > [ 4.154434] i915 0000:00:02.0: [drm] fb1: i915drmfb frame buffer devic= e > ... > [ 44.630789] simple-framebuffer simple-framebuffer.0: swiotlb buffer > is full (sz: 1310720 bytes), total 32768 (slots), used 0 (slots) > ... > > The last message might be due to the display manager starting up. > > Hope it helps. Thank you for your testing. Jaak's problem seems related to the initialization order, you can try to modify drivers/gpu/drm/Makefile, move obj-y +=3D tiny/ to between these two lines obj-$(CONFIG_DRM_SCHED) +=3D scheduler/ obj-$(CONFIG_DRM_RADEON)+=3D radeon/ then build a new 6.5.x kernel to see whether your problem is resolved. Evan's problem seems a little strange, could you please give me your config files of both 6.4.12 and 6.5.x? And you can also try the above method to see if anything changes. Huacai > > J > > > > >> > >> Evan > >> > >>> > >>> Huacai > >>> > >>>> > >>>> Evan > >>>> > >>>>> > >>>>> Huacai > >>>>> > >>>>>> > >>>>>> Jaak > >>>>>> > >>>>>>> > >>>>>>> > >>>>>>> Huacai > >>>>>>> > >>>>>>>> > >>>>>>>> Huacai > >>>>>>>> > >>>>>>>>> > >>>>>>>>> Jaak > >>>>>>>>> > >>>>>>>>>> > >>>>>>>>>> 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 on= ly a blank > >>>>>>>>>>>>>> screen after boot and a rapidly flashing device-access-sta= tus > >>>>>>>>>>>>>> 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 des= cription says > >>>>>>>>>>>>> that this is not a common configuration, so can we maybe ge= t away with that? > >>>>>>>>>>>> From my point of view, this is not a regression, 60aebc9= 559492c > >>>>>>>>>>>> doesn't cause a problem, but exposes a problem. So we need t= o fix the > >>>>>>>>>>>> real problem (SIMPLEDRM has a blank screen on some condition= s). 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 tra= cking: > >>>>>>>>>>>>> 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 ("drive= rs/firmware: Move > >>>>>>>>>>>>>>>>>>> sysfb_init() from device_initcall to subsys_initcall_= sync") there is > >>>>>>>>>>>>>>>>>>> no platform device created for SIMPLEDRM at early sta= ge, so it seems > >>>>>>>>>>>>>>>>>>> also "no problem". > >>>>>>>>>>>>>>>>>> I don't understand above. You mean that after that com= mit the platform > >>>>>>>>>>>>>>>>>> device is also none, right? > >>>>>>>>>>>>>>>>> No. The SIMPLEDRM driver needs a platform device to wor= k, and that > >>>>>>>>>>>>>>>>> commit makes the platform device created earlier. So, b= efore that > >>>>>>>>>>>>>>>>> commit, SIMPLEDRM doesn't work, but the screen isn't bl= ank; after that > >>>>>>>>>>>>>>>>> commit, SIMPLEDRM works, but the screen is blank. > >>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>> Huacai > >>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>> Confused... > >>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>> -- > >>>>>>>>>>>>>>>>>> An old man doll... just what I always wanted! - Clara > >>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> > >>>>>>>>>>> > >>>>>>>>> > >>>>>> > >>>> > >>>> >