[Intel-gfx] WARNING on i915 - intel_panel

[Pedro Ribeiro]

Hi,

I'm getting this error consistently with the Debian 3.14.4 after
resuming from hibernation:

[  931.032142] ------------[ cut here ]------------
[  931.032209] WARNING: CPU: 0 PID: 4715 at
/build/linux-Zc5oK7/linux-3.14.4/drivers/gpu/drm/i915/intel_panel.c:723
i965_enable_backlight+0x122/0x150 [i915]()
[  931.032219] backlight already enabled
[  931.032223] Modules linked in: ctr ccm cpufreq_stats
cpufreq_userspace cpufreq_conservative cpufreq_powersave pci_stub
vboxpci(O) vboxnetadp(O) vboxnetflt(O) vboxdrv(O) binfmt_misc
nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables xt_tcpudp
xt_conntrack iptable_filter iptable_nat nf_conntrack_ipv4
nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack ip_tables x_tables fuse
vmwgfx ttm vmxnet3 tp_smapi(O) thinkpad_ec(O) loop ppdev lp btusb
bluetooth 6lowpan_iphc crc16 snd_hda_codec_conexant
snd_hda_codec_generic coretemp kvm_intel uvcvideo kvm
videobuf2_vmalloc videobuf2_memops videobuf2_core videodev media
psmouse serio_raw arc4 evdev iwldvm snd_hda_intel snd_hda_codec
snd_hwdep snd_pcm_oss thinkpad_acpi mac80211 snd_mixer_oss nvram
snd_pcm snd_seq_midi i2c_i801 snd_seq_midi_event lpc_ich snd_rawmidi
mfd_core snd_seq snd_seq_device snd_timer iwlwifi cfg80211 snd wmi
soundcore rfkill battery ac parport_pc tpm_tis parport i915 tpm video
drm_kms_helper drm i2c_algo_bit i2c_core acpi_cpufreq mei_me mei
processor button xfs crc32c libcrc32c lzo sg hid_generic usbhid hid
sd_mod crct10dif_generic sr_mod crc_t10dif cdrom crct10dif_common
firewire_ohci firewire_core crc_itu_t ahci libahci libata scsi_mod
thermal thermal_sys uhci_hcd ehci_pci ehci_hcd usbcore usb_common
e1000e ptp pps_core
[  931.032448] CPU: 0 PID: 4715 Comm: kworker/u8:89 Tainted: G
  O 3.14-1-amd64 #1 Debian 3.14.4-1
[  931.032456] Hardware name: LENOVO 7417PLU/7417PLU, BIOS 7VET95WW
(3.25 ) 10/10/2012
[  931.032470] Workqueue: events_unbound async_run_entry_fn
[  931.032476]  0000000000000009 ffffffff814b9b42 ffff8800a6369af8
ffffffff8105f0a2
[  931.032488]  ffff880232b04000 ffff8800a6369b48 ffff8802301ac000
00000000e0000000
[  931.032498]  ffff8800b870d000 ffffffff8105f107 ffffffffa0392f9b
ffffffff00000018
[  931.032508] Call Trace:
[  931.032522]  [<ffffffff814b9b42>] ? dump_stack+0x41/0x51
[  931.032532]  [<ffffffff8105f0a2>] ? warn_slowpath_common+0x72/0x90
[  931.032541]  [<ffffffff8105f107>] ? warn_slowpath_fmt+0x47/0x50
[  931.032576]  [<ffffffffa0366782>] ? gen4_read32+0x32/0xa0 [i915]
[  931.032609]  [<ffffffffa034f2f2>] ? i965_enable_backlight+0x122/0x150 [i915]
[  931.032644]  [<ffffffffa035025c>] ?
intel_panel_enable_backlight+0x9c/0xe0 [i915]
[  931.032676]  [<ffffffffa03663c0>] ? gen4_write64+0x90/0x90 [i915]
[  931.032709]  [<ffffffffa0330181>] ? i9xx_crtc_enable+0x2e1/0x400 [i915]
[  931.032743]  [<ffffffffa03329ee>] ? __intel_set_mode+0x85e/0x15a0 [i915]
[  931.032779]  [<ffffffffa0338c49>] ?
intel_modeset_setup_hw_state+0xb09/0xc10 [i915]
[  931.032808]  [<ffffffffa02fd2ca>] ? __i915_drm_thaw+0x15a/0x210 [i915]
[  931.032834]  [<ffffffffa02fd3d1>] ? i915_resume+0x51/0x70 [i915]
[  931.032844]  [<ffffffff812b0da0>] ? pci_pm_suspend_noirq+0x190/0x190
[  931.032854]  [<ffffffff8136cd8e>] ? dpm_run_callback+0x2e/0x70
[  931.032862]  [<ffffffff8136ce9c>] ? device_resume+0x8c/0x180
[  931.032870]  [<ffffffff8136cfa4>] ? async_resume+0x14/0x40
[  931.032880]  [<ffffffff8108503d>] ? async_run_entry_fn+0x2d/0x120
[  931.032890]  [<ffffffff81078b9d>] ? process_one_work+0x16d/0x420
[  931.032899]  [<ffffffff81079756>] ? worker_thread+0x116/0x3b0
[  931.032908]  [<ffffffff81079640>] ? rescuer_thread+0x330/0x330
[  931.032917]  [<ffffffff8107f911>] ? kthread+0xc1/0xe0
[  931.032925]  [<ffffffff8107f850>] ? kthread_create_on_node+0x180/0x180
[  931.032934]  [<ffffffff814c73cc>] ? ret_from_fork+0x7c/0xb0
[  931.032943]  [<ffffffff8107f850>] ? kthread_create_on_node+0x180/0x180
[  931.032950] ---[ end trace a83af26b25b25474 ]---

My hardware is a Lenovo T400 with a GM45.

Does this mean anything to you? Please let me know if there is
anything else you need.

Regards,
Pedro