WARNING: CPU: 2 PID: 42 at drivers/gpu/drm/drm_modeset_lock.c:276

Wed Dec 28 11:26:16 UTC 2022

Hi,

Am 21.12.22 um 20:46 schrieb Stefan Wahren:
> Hi,
>
> if i enable PROVE_LOCKING on the Raspberry Pi 3 B+ 
> (arm/multi_v7_defconfig) using v6.1 (didn't test older versions) i'm 
> getting the following warning:
>
> [  204.043396] WARNING: CPU: 2 PID: 42 at 
> drivers/gpu/drm/drm_modeset_lock.c:276 drm_modeset_drop_locks+0x6c/0x70
> [  204.043426] Modules linked in: aes_arm aes_generic cmac 
> bcm2835_v4l2(C) bcm2835_mmal_vchiq(C) videobuf2_vmalloc 
> videobuf2_memops videobuf2_v4l2 videobuf2_common videodev mc 
> snd_bcm2835(C) crc32_arm_ce brcmfmac brcmutil vc4 snd_soc_hdmi_codec 
> sha256_generic libsha256 snd_soc_core ac97_bus snd_pcm_dmaengine 
> snd_pcm sha256_arm snd_timer cfg80211 onboard_usb_hub snd hci_uart 
> raspberrypi_hwmon soundcore drm_dma_helper btbcm bluetooth 
> ecdh_generic bcm2835_thermal ecc libaes vchiq(C) microchip lan78xx
> [  204.043820] CPU: 2 PID: 42 Comm: kworker/2:1 Tainted: G C         
> 6.1.0-00007-g22fada783b9f #31
> [  204.043833] Hardware name: BCM2835
> [  204.043842] Workqueue: events output_poll_execute
> [  204.043866]  unwind_backtrace from show_stack+0x10/0x14
> [  204.043886]  show_stack from dump_stack_lvl+0x58/0x70
> [  204.043903]  dump_stack_lvl from __warn+0xc8/0x1e8
> [  204.043920]  __warn from warn_slowpath_fmt+0x5c/0xb8
> [  204.043936]  warn_slowpath_fmt from drm_modeset_drop_locks+0x6c/0x70
> [  204.043952]  drm_modeset_drop_locks from 
> drm_helper_probe_detect_ctx+0xd4/0x124
> [  204.043969]  drm_helper_probe_detect_ctx from 
> output_poll_execute+0x154/0x230
> [  204.043986]  output_poll_execute from process_one_work+0x288/0x708
> [  204.044004]  process_one_work from worker_thread+0x54/0x50c
> [  204.044020]  worker_thread from kthread+0xe8/0x104
> [  204.044034]  kthread from ret_from_fork+0x14/0x2c
> [  204.044048] Exception stack(0xf0915fb0 to 0xf0915ff8)
> [  204.044059] 5fa0:                                     00000000 
> 00000000 00000000 00000000
> [  204.044070] 5fc0: 00000000 00000000 00000000 00000000 00000000 
> 00000000 00000000 00000000
> [  204.044080] 5fe0: 00000000 00000000 00000000 00000000 00000013 
> 00000000
> [  204.044090] irq event stamp: 33189
> [  204.044100] hardirqs last  enabled at (33195): [<c03ba3b4>] 
> __up_console_sem+0x50/0x60
> [  204.044120] hardirqs last disabled at (33200): [<c03ba3a0>] 
> __up_console_sem+0x3c/0x60
> [  204.044136] softirqs last  enabled at (32836): [<c0366478>] 
> process_one_work+0x288/0x708
> [  204.044152] softirqs last disabled at (32832): [<c0fb7134>] 
> neigh_managed_work+0x18/0xa4
> [  204.044168] ---[ end trace 0000000000000000 ]---

here are my intermediate results. I'm stuck during bisecting. For the 
skipped steps either vc4 throw compile errors or X doesn't come up 
(display goes black before X and says no connection).

$ git bisect log
git bisect start
# good: [4fe89d07dcc2804c8b562f6c7896a45643d34b2f] Linux 6.0
git bisect good 4fe89d07dcc2804c8b562f6c7896a45643d34b2f
# bad: [33e591dee915832c618cf68bb1058c8e7d296128] Merge tag 
'phy-for-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/phy/linux-phy
git bisect bad 33e591dee915832c618cf68bb1058c8e7d296128
# good: [a47e60729d9624e931f988709ab76e043e2ee8b9] Merge tag 
'backlight-next-6.1' of 
git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight
git bisect good a47e60729d9624e931f988709ab76e043e2ee8b9
# bad: [ff6862c23d2e83d12d1759bf4337d41248fb4dc8] Merge tag 
'arm-drivers-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
git bisect bad ff6862c23d2e83d12d1759bf4337d41248fb4dc8
# good: [95d8c67187bcfaa519bafcdef9091cd906505454] Merge tag 
'drm-msm-next-2022-09-22' of https://gitlab.freedesktop.org/drm/msm into 
drm-next
git bisect good 95d8c67187bcfaa519bafcdef9091cd906505454
# good: [86a4d29e75540e20f991e72f17aa51d0e775a397] Merge tag 'asoc-v6.1' 
of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into 
for-linus
git bisect good 86a4d29e75540e20f991e72f17aa51d0e775a397
# bad: [65898687cf7392c372ea8d04a88617e2cb794465] Merge tag 
'amd-drm-next-6.1-2022-09-30' of 
https://gitlab.freedesktop.org/agd5f/linux into drm-next
git bisect bad 65898687cf7392c372ea8d04a88617e2cb794465
# good: [2d89e2ddfd00ca569dd73883c7c70badbd57f4ac] drm/amdgpu: fix 
compiler warning for amdgpu_gfx_cp_init_microcode
git bisect good 2d89e2ddfd00ca569dd73883c7c70badbd57f4ac
# bad: [1637c315282e97efcb95cc7dfafbb15efa9fa27f] drm/mediatek: dp: Fix 
compiler warning in mtk_dp_video_mute()
git bisect bad 1637c315282e97efcb95cc7dfafbb15efa9fa27f
# skip: [b78e5d830f0db8e6d998cdc5a2b7b807cf463f99] drm/tests: Set also 
mock plane src_x, src_y, src_w and src_h
git bisect skip b78e5d830f0db8e6d998cdc5a2b7b807cf463f99
# skip: [213cb76ddc8b875e772f9f4d173feefa122716af] Merge tag 
'drm-intel-gt-next-2022-09-09' of 
git://anongit.freedesktop.org/drm/drm-intel into drm-next
git bisect skip 213cb76ddc8b875e772f9f4d173feefa122716af
# good: [4f96b1bc156e7076f6efedc2a76a8c7e897c7977] drm/todo: Add entry 
about dealing with brightness control on devices with > 1 panel
git bisect good 4f96b1bc156e7076f6efedc2a76a8c7e897c7977
# skip: [165ba1aad164b7d5d5bc327fa511f6ef693b207b] drm/vc4: hdmi: Switch 
to detect_ctx
git bisect skip 165ba1aad164b7d5d5bc327fa511f6ef693b207b
# skip: [c0895f80272cd4100a26129f4fb91a85bf6663a1] drm/vc4: hdmi: 
Simplify the hotplug handling
git bisect skip c0895f80272cd4100a26129f4fb91a85bf6663a1
# bad: [98a65e6d498c46b0beec7a40aac4b3e404642993] drm/rockchip: remove 
vop_writel from vop1 driver
git bisect bad 98a65e6d498c46b0beec7a40aac4b3e404642993
# skip: [385d1bba890f9b94322ca7fdfa778311f1ea0813] drm/modes: Add 
initializer macro DRM_MODE_INIT()
git bisect skip 385d1bba890f9b94322ca7fdfa778311f1ea0813
# skip: [d25654b3fad9906ca80912701fd4bd6e2419f54d] drm/probe-helper: Add 
drm_connector_helper_get_modes_fixed()
git bisect skip d25654b3fad9906ca80912701fd4bd6e2419f54d
# skip: [6d6e732835db92e66c28dbcf258a7e3d3c71420d] drm/udl: Restore 
display mode on resume
git bisect skip 6d6e732835db92e66c28dbcf258a7e3d3c71420d
# skip: [f2912237eb922bf2d4ebf13f3f5f1b25070f1e52] drm/aperture: Fix 
some kerneldoc comments
git bisect skip f2912237eb922bf2d4ebf13f3f5f1b25070f1e52
# skip: [68ded02cb2c23f1aebf026196a793959bd0463dc] drm/scdc: Document 
hotplug gotchas
git bisect skip 68ded02cb2c23f1aebf026196a793959bd0463dc
# skip: [216b9bbaeaea96b7f05c220f61855d174be972d8] drm/probe-helper: Add 
drm_crtc_helper_mode_valid_fixed()
git bisect skip 216b9bbaeaea96b7f05c220f61855d174be972d8

>
> Best regards
>