Not sure if this is the correct place to report.
This error occured when using 1de5b5a91c4b101eedb825790a852a19b755faed from
https://cgit.freedesktop.org/~agd5f/linux/log/?h=3Damd-staging-drm=
-next
Backlight is not ajustable
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[ 2.321821] amdgpu: [powerplay] dpm has been enabled
[ 2.322244] [drm:construct [amdgpu]] *ERROR* construct: Invalid Connector
ObjectID from Adapter Service for connector index:2! type 0 expected 3
[ 2.330448] [drm] Display Core initialized with v3.1.38!
[ 2.337391] [drm] SADs count is: -2, don't need to read it
[ 2.338216] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[ 2.338217] [drm] Driver supports precise vblank timestamp query.
[ 2.348435] input: SynPS/2 Synaptics TouchPad as
/devices/platform/i8042/serio1/input/input9
[ 2.350703] mousedev: PS/2 mouse device common for all mice
[ 2.361727] [drm] VCN decode and encode initialized successfully.
[ 2.371890] [drm] fb mappable at 0xD1000000
[ 2.371892] [drm] vram apper at 0xD0000000
[ 2.371893] [drm] size 8294400
[ 2.371893] [drm] fb depth is 24
[ 2.371894] [drm] pitch is 7680
[ 2.371970] fbcon: amdgpudrmfb (fb0) is primary device
[ 2.380213] Console: switching to colour frame buffer device 240x67
[ 2.400728] amdgpu 0000:04:00.0: fb0: amdgpudrmfb frame buffer device
[ 2.408049] amdgpu 0000:04:00.0: ring 0(gfx) uses VM inv eng 4 on hub 0
[ 2.408051] amdgpu 0000:04:00.0: ring 1(comp_1.0.0) uses VM inv eng 5 on=
hub
0
[ 2.408053] amdgpu 0000:04:00.0: ring 2(comp_1.1.0) uses VM inv eng 6 on=
hub
0
[ 2.408054] amdgpu 0000:04:00.0: ring 3(comp_1.2.0) uses VM inv eng 7 on=
hub
0
[ 2.408055] amdgpu 0000:04:00.0: ring 4(comp_1.3.0) uses VM inv eng 8 on=
hub
0
[ 2.408056] amdgpu 0000:04:00.0: ring 5(comp_1.0.1) uses VM inv eng 9 on=
hub
0
[ 2.408058] amdgpu 0000:04:00.0: ring 6(comp_1.1.1) uses VM inv eng 10 on
hub 0
[ 2.408059] amdgpu 0000:04:00.0: ring 7(comp_1.2.1) uses VM inv eng 11 on
hub 0
[ 2.408060] amdgpu 0000:04:00.0: ring 8(comp_1.3.1) uses VM inv eng 12 on
hub 0
[ 2.408062] amdgpu 0000:04:00.0: ring 9(kiq_2.1.0) uses VM inv eng 13 on=
hub
0
[ 2.408063] amdgpu 0000:04:00.0: ring 10(sdma0) uses VM inv eng 4 on hub=
1
[ 2.408064] amdgpu 0000:04:00.0: ring 11(vcn_dec) uses VM inv eng 5 on h=
ub 1
[ 2.408066] amdgpu 0000:04:00.0: ring 12(vcn_enc0) uses VM inv eng 6 on =
hub
1
[ 2.408067] amdgpu 0000:04:00.0: ring 13(vcn_enc1) uses VM inv eng 7 on =
hub
1
[ 2.414993] [drm] Initialized amdgpu 3.25.0 20150101 for 0000:04:00.0 on
minor 0
[ 2.431885] BUG: unable to handle kernel NULL pointer dereference at
000000000000023c
[ 2.431934] IP: dc_link_set_backlight_level+0x5e/0x160 [amdgpu]
[ 2.431948] PGD 0 P4D 0=20
[ 2.431957] Oops: 0000 [#1] PREEMPT SMP NOPTI
[ 2.431968] Modules linked in: joydev mousedev hid_sensor_accel_3d
hid_sensor_magn_3d hid_sensor_gyro_3d hid_sensor_rotation hid_sensor_incl_3d
hid_sensor_trigger industrialio_triggered_buffer kfifo_buf
hid_sensor_iio_common industrialio hid_sensor_hub hid_generic btusb btrtl b=
tbcm
btintel bluetooth usbhid ecdh_generic msr cdc_ether usbnet r8152 mii uvcvid=
eo
videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_core videodev m=
edia
amdkfd amd_iommu_v2 nls_iso8859_1 nls_cp437 vfat fat arc4 amdgpu r8822be(C)
snd_hda_codec_realtek chash snd_hda_codec_generic gpu_sched snd_hda_codec_h=
dmi
snd_hda_intel mac80211 hp_wmi ttm edac_mce_amd sparse_keymap wmi_bmof
snd_hda_codec ccp snd_hda_core drm_kms_helper snd_hwdep snd_pcm cfg80211 drm
syscopyarea rtsx_pci_ms kvm sysfillrect snd_timer sysimgblt fb_sys_fops
[ 2.432149] i2c_algo_bit snd irqbypass rfkill memstick soundcore evdev
input_leds tpm_crb crct10dif_pclmul sp5100_tco ghash_clmulni_intel tpm_tis
psmouse mac_hid pcspkr i2c_piix4 tpm_tis_core shpchp tpm hp_accel i2c_hid
battery ac thermal wmi rng_core lis3lv02d i2c_scmi input_polldev video hid
pinctrl_amd hp_wireless led_class button acpi_cpufreq sch_fq_codel sg
crypto_user ip_tables x_tables ext4 crc16 mbcache jbd2 fscrypto rtsx_pci_sd=
mmc
mmc_core serio_raw atkbd libps2 crc32_pclmul crc32c_intel ahci aesni_intel
aes_x86_64 libahci crypto_simd cryptd glue_helper xhci_pci libata xhci_hcd
scsi_mod usbcore usb_common nvme rtsx_pci nvme_core i8042 serio
[ 2.432298] CPU: 2 PID: 664 Comm: systemd-backlig Tainted: G C=
=20=20=20=20=20=20
4.16.0-rc1-165278df2b50 #12
[ 2.432319] Hardware name: HP HP ENVY x360 Convertible 15-bq1xx/83C6, BI=
OS
F.13 11/10/2017
[ 2.432354] RIP: 0010:dc_link_set_backlight_level+0x5e/0x160 [amdgpu]
[ 2.432369] RSP: 0018:ffffbb53c2233d78 EFLAGS: 00010286
[ 2.432382] RAX: 0000000000000000 RBX: 0000000000000000 RCX:
ffffffffc12756a0
[ 2.432398] RDX: ffff9ac775febe00 RSI: 00000000000000ff RDI:
ffff9ac78af15740
[ 2.432414] RBP: ffff9ac78af15080 R08: 00000000000000ff R09:
0000000000000003
[ 2.432430] R10: 000000000000000a R11: f000000000000000 R12:
ffff9ac78444b438
[ 2.432446] R13: ffff9ac784b18000 R14: 0000000000000000 R15:
ffff9ac77c06d000
[ 2.432469] FS: 00007f830b4b68c0(0000) GS:ffff9ac79ec80000(0000)
knlGS:0000000000000000
[ 2.432509] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2.432539] CR2: 000000000000023c CR3: 0000000409710000 CR4:
00000000003406e0
[ 2.432575] Call Trace:
[ 2.432636] amdgpu_dm_backlight_update_status+0x21/0x30 [amdgpu]
[ 2.432671] backlight_device_set_brightness+0x76/0xc0
[ 2.432701] brightness_store+0x5b/0x70
[ 2.432725] kernfs_fop_write+0x10f/0x190
[ 2.432750] __vfs_write+0x36/0x160
[ 2.432772] ? __check_object_size+0xa7/0x1a0
[ 2.432797] vfs_write+0xad/0x1a0
[ 2.432817] SyS_write+0x52/0xc0
[ 2.432838] do_syscall_64+0x68/0x120
[ 2.432861] entry_SYSCALL_64_after_hwframe+0x21/0x86
[ 2.432889] RIP: 0033:0x7f830b018444
[ 2.432909] RSP: 002b:00007fffffa8b2c8 EFLAGS: 00000246 ORIG_RAX:
0000000000000001
[ 2.434488] RAX: ffffffffffffffda RBX: 00005645b994e420 RCX:
00007f830b018444
[ 2.434491] RDX: 0000000000000003 RSI: 00005645b994e420 RDI:
0000000000000004
[ 2.436957] RBP: 00007fffffa8b3b0 R08: 0000000000000000 R09:
00007f830b0680d0
[ 2.436958] R10: 00005645b993cac0 R11: 0000000000000246 R12:
0000000000000003
[ 2.436958] R13: 00005645b9937dc0 R14: 00005645b83ca8ec R15:
0000000000000004
[ 2.436961] Code: 00 00 48 8b a8 80 02 00 00 48 85 ff 0f 84 ff 00 00 00 =
48
85 ed 0f 84 f6 00 00 00 48 89 cb 48 8b 4d 08 31 c0 48 83 79 20 00 74 60 <=
;8b> 83
3c 02 00 00 89 b3 3c 02 00 00 41 89 f4 85 c0 b8 00 00 00=20
[ 2.442198] RIP: dc_link_set_backlight_level+0x5e/0x160 [amdgpu] RSP:
ffffbb53c2233d78
[ 2.445142] CR2: 000000000000023c
[ 2.445143] ---[ end trace eaaf2b469433a7e1 ]---
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