On 17.05.23 17:15, Linux regression tracking (Thorsten Leemhuis) wrote: > Hi, Thorsten here, the Linux kernel's regression tracker. Top-posting > for once, to make this easily accessible to everyone. > > Dmitry, was any progress made to address this regression? Doesn't look > like it, but I strongly suspect I'm missing something, FWIW, I'm dropping this from the regression tracking. It might be still around, but it's a warning and nothing that really breaks things afaics. Please holler if I got this wrong and think it's something that needs to be fixed to ensure the "no regressions" rule is adhered. #regzbot inconclusive: a warn() without serious impact, see discussion #regzbot ignore-activity 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. > as I'm not really > sure if I properly understood this thread. It sounded a bit like > a4e771729a51 should be reverted for now until all > drm_kms_helper_poll_disable() calls have been verified. Is that right? > Or did somebody already verify and fix all of them with bugs? > > On 28.04.23 03:17, zongmin zhou wrote: >> On Wed, 2023-04-26 at 16:10 +0300, Dmitry Baryshkov wrote: >>> On Wed, 26 Apr 2023 at 12:09, zongmin zhou <zhouzongmin@xxxxxxxxxx> >>> wrote: >>>> On Sun, 2023-04-23 at 22:51 +0200, Janne Grunau wrote: >>>>> On 2023-04-20 23:07:01 +0300, Dmitry Baryshkov wrote: >>>>>> On Thu, 20 Apr 2023 at 23:01, Janne Grunau <j@xxxxxxxxxx> >>>>>> wrote: >>>>>>> >>>>>>> On 2023-03-28 10:31:29 +0800, Zongmin Zhou wrote: >>>>>>>> When drivers call drm_kms_helper_poll_disable from >>>>>>>> their device suspend implementation without enabled output >>>>>>>> polling before, >>>>>>>> following warning will be reported,due to work->func not be >>>>>>>> initialized: >>>>>>> >>>>>>> we see the same warning with the wpork in progress kms driver >>>>>>> for >>>>>>> apple >>>>>>> silicon SoCs. The connectors do not need to polled so the >>>>>>> driver >>>>>>> never >>>>>>> calls drm_kms_helper_poll_init(). >>>>>>> >>>>>>>> [ 55.141361] WARNING: CPU: 3 PID: 372 at >>>>>>>> kernel/workqueue.c:3066 __flush_work+0x22f/0x240 >>>>>>>> [ 55.141382] Modules linked in: nls_iso8859_1 >>>>>>>> snd_hda_codec_generic ledtrig_audio snd_hda_intel >>>>>>>> snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec >>>>>>>> snd_hda_core >>>>>>>> snd_hwdep snd_pcm snd_seq_midi snd_seq_midi_event >>>>>>>> snd_rawmidi >>>>>>>> snd_seq intel_rapl_msr intel_rapl_common bochs >>>>>>>> drm_vram_helper >>>>>>>> drm_ttm_helper snd_seq_device nfit ttm crct10dif_pclmul >>>>>>>> snd_timer ghash_clmulni_intel binfmt_misc sha512_ssse3 >>>>>>>> aesni_intel drm_kms_helper joydev input_leds syscopyarea >>>>>>>> crypto_simd snd cryptd sysfillrect sysimgblt mac_hid >>>>>>>> serio_raw >>>>>>>> soundcore qemu_fw_cfg sch_fq_codel msr parport_pc ppdev lp >>>>>>>> parport drm ramoops reed_solomon pstore_blk pstore_zone >>>>>>>> efi_pstore virtio_rng ip_tables x_tables autofs4 >>>>>>>> hid_generic >>>>>>>> usbhid hid ahci virtio_net i2c_i801 crc32_pclmul psmouse >>>>>>>> virtio_scsi libahci i2c_smbus lpc_ich xhci_pci net_failover >>>>>>>> virtio_blk xhci_pci_renesas failover >>>>>>>> [ 55.141430] CPU: 3 PID: 372 Comm: kworker/u16:9 Not >>>>>>>> tainted >>>>>>>> 6.2.0-rc6+ #16 >>>>>>>> [ 55.141433] Hardware name: QEMU Standard PC (Q35 + ICH9, >>>>>>>> 2009), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org >>>>>>>> 04/01/2014 >>>>>>>> [ 55.141435] Workqueue: events_unbound async_run_entry_fn >>>>>>>> [ 55.141441] RIP: 0010:__flush_work+0x22f/0x240 >>>>>>>> [ 55.141444] Code: 8b 43 28 48 8b 53 30 89 c1 e9 f9 fe ff >>>>>>>> ff >>>>>>>> 4c 89 f7 e8 b5 95 d9 00 e8 00 53 08 00 45 31 ff e9 11 ff ff >>>>>>>> ff >>>>>>>> 0f 0b e9 0a ff ff ff <0f> 0b 45 31 ff e9 00 ff ff ff e8 e2 >>>>>>>> 54 >>>>>>>> d8 00 66 90 90 90 90 90 90 >>>>>>>> [ 55.141446] RSP: 0018:ff59221940833c18 EFLAGS: 00010246 >>>>>>>> [ 55.141449] RAX: 0000000000000000 RBX: 0000000000000000 >>>>>>>> RCX: >>>>>>>> ffffffff9b72bcbe >>>>>>>> [ 55.141450] RDX: 0000000000000001 RSI: 0000000000000001 >>>>>>>> RDI: >>>>>>>> ff3ea01e4265e330 >>>>>>>> [ 55.141451] RBP: ff59221940833c90 R08: 0000000000000000 >>>>>>>> R09: >>>>>>>> 8080808080808080 >>>>>>>> [ 55.141453] R10: ff3ea01e42b3caf4 R11: 000000000000000f >>>>>>>> R12: >>>>>>>> ff3ea01e4265e330 >>>>>>>> [ 55.141454] R13: 0000000000000001 R14: ff3ea01e505e5e80 >>>>>>>> R15: >>>>>>>> 0000000000000001 >>>>>>>> [ 55.141455] FS: 0000000000000000(0000) >>>>>>>> GS:ff3ea01fb7cc0000(0000) knlGS:0000000000000000 >>>>>>>> [ 55.141456] CS: 0010 DS: 0000 ES: 0000 CR0: >>>>>>>> 0000000080050033 >>>>>>>> [ 55.141458] CR2: 0000563543ad1546 CR3: 000000010ee82005 >>>>>>>> CR4: >>>>>>>> 0000000000771ee0 >>>>>>>> [ 55.141464] DR0: 0000000000000000 DR1: 0000000000000000 >>>>>>>> DR2: >>>>>>>> 0000000000000000 >>>>>>>> [ 55.141465] DR3: 0000000000000000 DR6: 00000000fffe0ff0 >>>>>>>> DR7: >>>>>>>> 0000000000000400 >>>>>>>> [ 55.141466] PKRU: 55555554 >>>>>>>> [ 55.141467] Call Trace: >>>>>>>> [ 55.141469] <TASK> >>>>>>>> [ 55.141472] ? pcie_wait_cmd+0xdf/0x220 >>>>>>>> [ 55.141478] ? mptcp_seq_show+0xe0/0x180 >>>>>>>> [ 55.141484] __cancel_work_timer+0x124/0x1b0 >>>>>>>> [ 55.141487] cancel_delayed_work_sync+0x17/0x20 >>>>>>>> [ 55.141490] drm_kms_helper_poll_disable+0x26/0x40 >>>>>>>> [drm_kms_helper] >>>>>>>> [ 55.141516] drm_mode_config_helper_suspend+0x25/0x90 >>>>>>>> [drm_kms_helper] >>>>>>>> [ 55.141531] ? __pm_runtime_resume+0x64/0x90 >>>>>>>> [ 55.141536] bochs_pm_suspend+0x16/0x20 [bochs] >>>>>>>> [ 55.141540] pci_pm_suspend+0x8b/0x1b0 >>>>>>>> [ 55.141545] ? __pfx_pci_pm_suspend+0x10/0x10 >>>>>>>> [ 55.141547] dpm_run_callback+0x4c/0x160 >>>>>>>> [ 55.141550] __device_suspend+0x14c/0x4c0 >>>>>>>> [ 55.141553] async_suspend+0x24/0xa0 >>>>>>>> [ 55.141555] async_run_entry_fn+0x34/0x120 >>>>>>>> [ 55.141557] process_one_work+0x21a/0x3f0 >>>>>>>> [ 55.141560] worker_thread+0x4e/0x3c0 >>>>>>>> [ 55.141563] ? __pfx_worker_thread+0x10/0x10 >>>>>>>> [ 55.141565] kthread+0xf2/0x120 >>>>>>>> [ 55.141568] ? __pfx_kthread+0x10/0x10 >>>>>>>> [ 55.141570] ret_from_fork+0x29/0x50 >>>>>>>> [ 55.141575] </TASK> >>>>>>>> [ 55.141575] ---[ end trace 0000000000000000 ]--- >>>>>>>> >>>>>>>> Fixes: a4e771729a51 ("drm/probe_helper: sort out >>>>>>>> poll_running >>>>>>>> vs poll_enabled") >>>>>>>> Signed-off-by: Zongmin Zhou<zhouzongmin@xxxxxxxxxx> >>>>>>>> --- >>>>>>>> drivers/gpu/drm/drm_probe_helper.c | 3 ++- >>>>>>>> 1 file changed, 2 insertions(+), 1 deletion(-) >>>>>>>> >>>>>>>> diff --git a/drivers/gpu/drm/drm_probe_helper.c >>>>>>>> b/drivers/gpu/drm/drm_probe_helper.c >>>>>>>> index 8127be134c39..ac72b18e2257 100644 >>>>>>>> --- a/drivers/gpu/drm/drm_probe_helper.c >>>>>>>> +++ b/drivers/gpu/drm/drm_probe_helper.c >>>>>>>> @@ -855,7 +855,8 @@ void drm_kms_helper_poll_disable(struct >>>>>>>> drm_device *dev) >>>>>>>> if (dev->mode_config.poll_running) >>>>>>>> drm_kms_helper_disable_hpd(dev); >>>>>>>> >>>>>>>> - cancel_delayed_work_sync(&dev- >>>>>>>>> mode_config.output_poll_work); >>>>>>>> + if (dev->mode_config.poll_enabled) >>>>>>>> + cancel_delayed_work_sync(&dev- >>>>>>>>> mode_config.output_poll_work); >>>>>>> >>>>>>> Checking for dev->mode_config.poll_enabled at the start of >>>>>>> the >>>>>>> function >>>>>>> and return early if it is not true looks more in style with >>>>>>> the >>>>>>> rest of >>>>>>> drm_probe_helper.c. >>>>>> >>>>>> I think it is an error to call drm_kms_helper_poll_disable() if >>>>>> polling was not initialized. So, in my opinion the fix should >>>>>> go to >>>>>> the drm_mode_config_helper_suspend() / _resume() instead. >>>>>> Please >>>>>> add a >>>>>> guard there using dev->mode_config.poll_enabled. >>>>> >>>>> While I tend to agree to the sentiment I do not think this is the >>>>> correct fix in this situation. drm_kms_helper_poll_disable had >>>>> the >>>>> check since at least 2014. a4e771729a51 is a regression. If we >>>>> want >>>>> to >>>>> change the behavior it should be done explicitly and after >>>>> verifying >>>>> all >>>>> drm_kms_helper_poll_disable() calls. >>>>> >>>>> #regzbot ^introduced a4e771729a51 >>>>> >>>>> ciao >>>>> Janne >>>> >>>> Dear Janne: >>>> >>>> I agree with you like I mentioned on last letter. >>>> Thanks for your time. >>>> >>>> >>>> Dear Dmitry: >>>> >>>> Is there anything else I can do? >>>> Looking forward to your reply. >>> >>> If it is a common consensus, I'm fine with your approach. >>> >> Dear Dmitry: >> >> Ok.Thanks for your reply. >> >> Best regards! >> >>
