Regression in i915 intel_panel_setup_backligh

[Daniel Exner]

Hi,

please keep me CC as I am currently not subscribed to the LKML.

I recently tested 3.17-rc7 and found my Samsung AtivBook 7 unable to
enable inteldrmfb (see attached output of the crash).

I managed to bisect it to:

commit 4dac3edfe68e5e1b3c2216b84ba160572420fa40
Merge: 4877776 e05444b
Author: Daniel Vetter <daniel.vetter@xxxxxxxx>
Date:   Tue Jul 29 20:49:36 2014 +0200

    Merge remote-tracking branch 'airlied/drm-next' into drm-intel-next

    Pull in drm-next with Dave's DP MST support so that I can merge some
    conflicting patches which also touch the driver load sequencing around
    interrupt handling.

    Conflicts:
        drivers/gpu/drm/i915/intel_display.c
        drivers/gpu/drm/i915/intel_dp.c

    Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxx>

git bisect log:
git bisect start 'v3.17.0-rc4' 'v3.15' 'drivers/gpu/drm/i915/intel_dp.c'
# bad: [2ce7598c9a453e0acd0e07be7be3f5eb39608ebd] Linux 3.17-rc4
git bisect bad 2ce7598c9a453e0acd0e07be7be3f5eb39608ebd
# good: [1860e379875dfe7271c649058aeddffe5afd9d0d] Linux 3.15
git bisect good 1860e379875dfe7271c649058aeddffe5afd9d0d
# good: [7c8f8a7007cf0069488e0b4e3db5f89d715f297e] drm/i915: Force PSR
exit by inactivating it.
git bisect good 7c8f8a7007cf0069488e0b4e3db5f89d715f297e
# good: [9ca153017e00550dbeda2718cfd69ca37de9c523] drm/i915: Fix up PSR
frontbuffer tracking
git bisect good 9ca153017e00550dbeda2718cfd69ca37de9c523
# bad: [5d42f82a9b8c5168d75cf59307cd271feca94464] Merge tag 'v3.16' into
drm-next
git bisect bad 5d42f82a9b8c5168d75cf59307cd271feca94464
# good: [0e32b39ceed665bfa4a77a4bc307b6652b991632] drm/i915: add DP 1.2
MST support (v0.7)
git bisect good 0e32b39ceed665bfa4a77a4bc307b6652b991632
# bad: [4dac3edfe68e5e1b3c2216b84ba160572420fa40] Merge remote-tracking
branch 'airlied/drm-next' into drm-intel-next
git bisect bad 4dac3edfe68e5e1b3c2216b84ba160572420fa40
# good: [eeefa889cddb8d7e4ee6ce0212e685dd624d66a1] drm/i915: Remove
redundant HAS_PSR checks
git bisect good eeefa889cddb8d7e4ee6ce0212e685dd624d66a1
# good: [4651fb23f6f1d86700b07a27ad7f137d28492342] drm/i915: remove
useless runtime PM get calls
git bisect good 4651fb23f6f1d86700b07a27ad7f137d28492342
# first bad commit: [4dac3edfe68e5e1b3c2216b84ba160572420fa40] Merge
remote-tracking branch 'airlied/drm-next' into drm-intel-next


Any thoughts on that?

Greetings
Daniel
-- 
Daniel Exner
Public-Key: https://www.dragonslave.de/pub_key.asc
[drm:drm_pci_init] 
[drm:drm_get_pci_dev] 
[drm:drm_minor_register] 
[drm:drm_minor_register] new minor registered 64
[drm:drm_minor_register] 
[drm:drm_minor_register] new minor registered 128
[drm:drm_minor_register] 
[drm:drm_minor_register] new minor registered 0
[drm:i915_dump_device_info] i915 device info: gen=7, pciid=0x0166 rev=0x09 flags=is_mobile,need_gfx_hws,is_ivybridge,has_fbc,has_hotplug,has_llc,
[drm:intel_detect_pch] Found PantherPoint PCH
[drm] Memory usable by graphics device = 2048M
[drm:i915_gem_gtt_init] GMADR size = 256M
[drm:i915_gem_gtt_init] GTT stolen size = 64M
[drm:i915_gem_gtt_init] ppgtt mode: 1
[drm] Replacing VGA console driver
checking generic (d0000000 1e0000) vs hw (d0000000 10000000)
fb: switching to inteldrmfb from EFI VGA
Console: switching to colour dummy device 80x25
[drm:intel_opregion_setup] graphic opregion physical addr: 0xc9b55018
[drm:intel_opregion_setup] Public ACPI methods supported
[drm:intel_opregion_setup] SWSCI supported
[drm:swsci_setup] SWSCI GBDA callbacks 00000cf3, SBCB callbacks 00000241
[drm:intel_opregion_setup] ASLE supported
i915 0000:00:02.0: irq 33 for MSI/MSI-X
[drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[drm] Driver supports precise vblank timestamp query.
[drm:init_vbt_defaults] Set default to SSC at 120000 kHz
[drm:validate_vbt] Using VBT from OpRegion: $VBT SNB/IVB-MOBILE d
[drm:parse_general_features] BDB_GENERAL_FEATURES int_tv_support 0 int_crt_support 1 lvds_use_ssc 0 lvds_ssc_freq 120000 display_clock_mode 0 fdi_rx_polarity_inverted 0
[drm:parse_general_definitions] crt_ddc_bus_pin: 2
[drm:parse_lfp_panel_data] DRRS supported mode is seamless
[drm:parse_lfp_panel_data] Found panel mode in BIOS VBT tables:
[drm:drm_mode_debug_printmodeline] Modeline 0:"1920x1080" 0 148500 1920 2008 2053 2200 1080 1083 1089 1125 0x8 0xa
[drm:parse_lfp_panel_data] VBT initial LVDS value 300
[drm:parse_lfp_backlight] VBT backlight PWM modulation frequency 210 Hz, active high, min brightness 255, level 255
[drm:parse_sdvo_panel_data] Found SDVO panel mode in BIOS VBT tables:
[drm:drm_mode_debug_printmodeline] Modeline 0:"1600x1200" 0 162000 1600 1664 1856 2160 1200 1201 1204 1250 0x8 0xa
[drm:parse_sdvo_device_mapping] No SDVO device info is found in VBT
[drm:parse_driver_features] DRRS State Enabled:0
[drm:intel_dsm_pci_probe] no _DSM method for intel device
[drm:i915_gem_init_stolen] found 67108864 bytes of stolen memory at cba00000
[drm:intel_display_power_get] enabling always-on
[drm:drm_irq_install] irq=33
[drm:intel_print_wm_latency] Primary WM0 latency 12 (1.2 usec)
[drm:intel_print_wm_latency] Primary WM1 latency 4 (2.0 usec)
[drm:intel_print_wm_latency] Primary WM2 latency 16 (8.0 usec)
[drm:intel_print_wm_latency] Primary WM3 latency 32 (16.0 usec)
[drm:intel_print_wm_latency] Sprite WM0 latency 12 (1.2 usec)
[drm:intel_print_wm_latency] Sprite WM1 latency 4 (2.0 usec)
[drm:intel_print_wm_latency] Sprite WM2 latency 16 (8.0 usec)
[drm:intel_print_wm_latency] Sprite WM3 latency 32 (16.0 usec)
[drm:intel_print_wm_latency] Cursor WM0 latency 12 (1.2 usec)
[drm:intel_print_wm_latency] Cursor WM1 latency 4 (2.0 usec)
[drm:intel_print_wm_latency] Cursor WM2 latency 16 (8.0 usec)
[drm:intel_print_wm_latency] Cursor WM3 latency 64 (32.0 usec)
[drm:intel_modeset_init] 3 display pipes available.
vgaarb: device changed decodes: PCI:0000:00:02.0,olddecodes=io+mem,decodes=io+mem:owns=io+mem
[drm:intel_lvds_init] LVDS is not present in VBT
[drm:drm_sysfs_connector_add] adding "VGA-1" to sysfs
[drm:drm_sysfs_hotplug_event] generating hotplug event
[drm:intel_crt_reset] pch crt adpa set to 0xf40000
[drm:intel_dp_init_connector] Adding eDP connector on port A
[drm:drm_sysfs_connector_add] adding "eDP-1" to sysfs
[drm:drm_sysfs_hotplug_event] generating hotplug event
[drm:intel_dp_init_panel_power_sequencer] cur t1_t3 2000 t8 800 t9 2000 t10 500 t11_t12 6000
[drm:intel_dp_init_panel_power_sequencer] vbt t1_t3 2000 t8 800 t9 2000 t10 500 t11_t12 5000
[drm:intel_dp_init_panel_power_sequencer] panel power up delay 200, power down delay 50, power cycle delay 600
[drm:intel_dp_init_panel_power_sequencer] backlight on delay 80, off delay 200
[drm:intel_dp_aux_init] registering DPDDC-A bus for card0-eDP-1
[drm:_edp_panel_vdd_on] Turning eDP VDD on
[drm:_edp_panel_vdd_on] PP_STATUS: 0x80000008 PP_CONTROL: 0xabcd000f
[drm:intel_dp_get_dpcd] DPCD: 11 0a 02 00 00 00 00 00 00 00 00 00 00 00 00
[drm:intel_dp_init_panel_power_sequencer_registers] panel power sequencer register settings: PP_ON 0x47d00001, PP_OFF 0x1f40001, PP_DIV 0x186906
[drm:drm_add_display_info] eDP-1: Assigning EDID-1.4 digital sink color depth as 8 bpc.
[drm:drm_edid_to_eld] ELD: no CEA Extension found
[drm] VBT doesn't support DRRS
divide error: 0000 [#1] PREEMPT SMP 
Modules linked in: i915(+) button video drm_kms_helper intel_gtt i2c_algo_bit drm agpgart ctr ccm af_packet bnep joydev iTCO_wdt iTCO_vendor_support ecb btusb uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core v4l2_common videodev bluetooth media x86_pkg_temp_thermal intel_powerclamp coretemp arc4 intel_rapl kvm_intel kvm evdev mac_hid snd_hda_codec_hdmi iwldvm psmouse snd_hda_codec_realtek mac80211 snd_hda_codec_generic microcode efivars serio_raw pcspkr iwlwifi cfg80211 r8169 rfkill snd_hda_intel snd_hda_controller i2c_i801 mii snd_hda_codec lpc_ich snd_hwdep shpchp thermal fan acpi_cpufreq tpm_infineon wmi processor thermal_sys battery tpm_tis hwmon tpm ac ppdev binfmt_misc snd_seq_dummy snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_oss snd_seq_midi_event snd_seq snd_seq_device snd_timer snd soundcore lp parport_pc parport ext4 crc16 jbd2 mbcache dm_crypt sd_mod crc_t10dif crct10dif_pclmul crct10dif_common crc32_pclmul crc32c_intel ghash_clmulni_intel aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd ehci_pci xhci_hcd ehci_hcd ahci libahci libata scsi_mod usbcore usb_common dm_mirror dm_region_hash dm_log dm_mod ipv6 autofs4 unix efivarfs [last unloaded: agpgart]
CPU: 0 PID: 2218 Comm: modprobe Not tainted 3.17.0-rc4-00355-g1536340 #9
Hardware name: SAMSUNG ELECTRONICS CO., LTD. 730U3E/740U3E/NP730U3E-X03DE, BIOS P05ABW.060.130530.dg 05/30/2013
task: ffff8800c311e250 ti: ffff8800c85dc000 task.ti: ffff8800c85dc000
RIP: 0010:[<ffffffffa1011bf6>]  [<ffffffffa1011bf6>] scale+0x36/0xa0 [i915]
RSP: 0018:ffff8800c85df8e8  EFLAGS: 00010206
RAX: 0000000000000000 RBX: ffff8800c2102400 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000122a
RBP: 0000000000000000 R08: 000000000000122a R09: ffff8800c8e32f00
R10: 00000000000003cd R11: 00000000000003cc R12: ffff880128a67510
R13: 0000000000000202 R14: ffff8800c8e04000 R15: ffff8800c836a600
FS:  00007f49f46e0700(0000) GS:ffff88012f200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbac9de1000 CR3: 00000000c7fd0000 CR4: 00000000001407f0
Stack:
 ffffffffa1013558 0000122a00000000 0000000000000000 0000000000000001
 ffff8800c2102400 ffff8801286ff000 ffff880128a60000 ffff8801286ff000
 ffffffffa1007902 ffff8800c8e040e0 ffff880128a60000 0000000000000000
Call Trace:
 [<ffffffffa1013558>] ? intel_panel_setup_backlight+0xf8/0x250 [i915]
 [<ffffffffa1007902>] ? intel_dp_init_connector+0x622/0x8d0 [i915]
 [<ffffffffa1007cf6>] ? intel_dp_init+0x146/0x200 [i915]
 [<ffffffffa0ff0551>] ? intel_modeset_init+0x11b1/0x1550 [i915]
 [<ffffffffa0fd31fe>] ? gen6_write32+0x2e/0x90 [i915]
 [<ffffffffa0fc3f6c>] ? ironlake_irq_postinstall+0xbc/0x190 [i915]
 [<ffffffffa101c898>] ? i915_driver_load+0xbb8/0x10a0 [i915]
 [<ffffffffa0f0f1bc>] ? drm_dev_register+0x9c/0xf0 [drm]
 [<ffffffffa0f11756>] ? drm_get_pci_dev+0xc6/0x1e0 [drm]
 [<ffffffff8123eb2a>] ? local_pci_probe+0x3a/0xa0
 [<ffffffff8123ea94>] ? pci_match_device+0xd4/0x100
 [<ffffffff8123ec5a>] ? pci_device_probe+0xca/0x120
 [<ffffffff812ee503>] ? driver_probe_device+0x83/0x250
 [<ffffffff812ee78b>] ? __driver_attach+0x7b/0x80
 [<ffffffff812ee710>] ? __device_attach+0x40/0x40
 [<ffffffff812ec913>] ? bus_for_each_dev+0x53/0x90
 [<ffffffff812edd08>] ? bus_add_driver+0x168/0x220
 [<ffffffffa105b000>] ? 0xffffffffa105b000
 [<ffffffff812eed26>] ? driver_register+0x56/0xd0
 [<ffffffff810002c8>] ? do_one_initcall+0x98/0x1f0
 [<ffffffff810b14bf>] ? load_module+0x1ccf/0x21b0
 [<ffffffff810ae230>] ? store_uevent+0x40/0x40
 [<ffffffff810b1abd>] ? SyS_finit_module+0x6d/0x70
 [<ffffffff81433ce9>] ? system_call_fastpath+0x16/0x1b
Code: d6 77 2f 44 39 c1 77 57 39 eb 89 e8 89 d6 0f 43 c3 39 d0 0f 47 c2 41 29 c8 29 de 29 d8 31 d2 48 83 c4 10 49 0f af c0 89 c9 5b 5d <48> f7 f6 48 01 c8 c3 be 9f 01 00 00 48 c7 c7 d8 d2 03 a1 44 89 
RIP  [<ffffffffa1011bf6>] scale+0x36/0xa0 [i915]
 RSP <ffff8800c85df8e8>
---[ end trace ff0f85d6a01208bd ]---
[drm:edp_panel_vdd_off_sync] Turning eDP VDD off
[drm:edp_panel_vdd_off_sync] PP_STATUS: 0x80000008 PP_CONTROL: 0xabcd0007