Additional info:
reporter:       libreport-2.2.3
WARNING: CPU: 1 PID: 208 at drivers/gpu/drm/i915/intel_panel.c:758 i9xx_enable_backlight+0xd4/0x100 [i915]()
backlight already enabled
Modules linked in: xor raid6_pq uas i915(+) e1000e ata_generic i2c_algo_bit pata_acpi drm_kms_helper usb_storage ptp pps_core drm yenta_socket i2c_core video
CPU: 1 PID: 208 Comm: systemd-udevd Not tainted 3.16.2-200.fc20.i686+PAE #1
Hardware name: LENOVO 1951A47/1951A47, BIOS 79ETE7WW (2.27 ) 03/21/2011
c0cb0907 d75fafd8 00000000 f33176e0 c0a1e41d f3317720 f3317710 c045e3ce
f82460dd f3317740 000000d0 f823f7a4 000002f6 f8217224 f8217224 f33e8000
f33f6400 f33f4c00 f331772c c045e42e 00000009 f3317720 f82460dd f3317740
Call Trace:
[<c0a1e41d>] dump_stack+0x41/0x52
[<c045e3ce>] warn_slowpath_common+0x7e/0xa0
[<f8217224>] ? i9xx_enable_backlight+0xd4/0x100 [i915]
[<f8217224>] ? i9xx_enable_backlight+0xd4/0x100 [i915]
[<c045e42e>] warn_slowpath_fmt+0x3e/0x60
[<f8217224>] i9xx_enable_backlight+0xd4/0x100 [i915]
[<f8218497>] intel_panel_enable_backlight+0x77/0xc0 [i915]
[<f82161af>] intel_enable_lvds+0x14f/0x160 [i915]
[<f81ed74d>] i9xx_crtc_enable+0x36d/0x400 [i915]
[<f81f193d>] __intel_set_mode+0x6cd/0x1400 [i915]
[<c049d027>] ? __wake_up_common+0x47/0x70
[<f81f4ce3>] intel_set_mode+0x23/0x40 [i915]
[<f81f5a34>] intel_crtc_set_config+0x7c4/0xba0 [i915]
[<c06c70fd>] ? ida_get_new_above+0x1bd/0x210
[<f7fce98e>] drm_mode_set_config_internal+0x4e/0xb0 [drm]
[<f81e8b00>] ? intel_reset_dpio+0x1a0/0x1a0 [i915]
[<f7f3e77a>] restore_fbdev_mode+0xaa/0xe0 [drm_kms_helper]
[<f7f3e7cd>] drm_fb_helper_restore_fbdev_mode_unlocked+0x1d/0x30 [drm_kms_helper]
[<f7f400c6>] drm_fb_helper_set_par+0x26/0x60 [drm_kms_helper]
[<c072691a>] fbcon_init+0x46a/0x4b0
[<c079e3ee>] visual_init+0x9e/0x100
[<c07a070a>] do_bind_con_driver+0x10a/0x2c0
[<c05e9e8c>] ? sysfs_create_file_ns+0x2c/0x30
[<c07a0dcd>] do_take_over_console+0xfd/0x190
[<c072204f>] do_fbcon_takeover+0x5f/0xc0
[<c07272af>] fbcon_event_notify+0x5ff/0x740
[<c0480af1>] notifier_call_chain+0x41/0x60
[<c0480e4b>] __blocking_notifier_call_chain+0x3b/0x60
[<c0480e8f>] blocking_notifier_call_chain+0x1f/0x30
[<c072c936>] fb_notifier_call_chain+0x16/0x20
[<c072e56a>] register_framebuffer+0x1ca/0x300
[<f7f403dc>] drm_fb_helper_initial_config+0x2dc/0xf00 [drm_kms_helper]
[<f81dc299>] ? gen4_write32+0x49/0xc0 [i915]
[<f81dc04f>] ? gen4_read32+0x3f/0xc0 [i915]
[<f8200213>] ? intel_fbdev_init+0x193/0x510 [i915]
[<f82005ac>] intel_fbdev_initial_config+0x1c/0x20 [i915]
[<f8221c3d>] i915_driver_load+0xe6d/0xef0 [i915]
[<f821ebe0>] ? i915_switcheroo_set_state+0x90/0x90 [i915]
[<c06c8c2a>] ? kobject_uevent_env+0x15a/0x560
[<c06c8840>] ? kobj_ns_drop+0x50/0x50
[<c07ca6e4>] ? get_device+0x14/0x30
[<c07cf4f2>] ? klist_class_dev_get+0x12/0x20
[<c0a1717e>] ? klist_node_init+0x2e/0x50
[<c0a17237>] ? klist_add_tail+0x27/0x30
[<c07cbbb6>] ? device_add+0x1d6/0x5a0
[<f7fc980e>] drm_dev_register+0x8e/0xe0 [drm]
[<f7fcbea9>] drm_get_pci_dev+0x79/0x1c0 [drm]
[<f81a1415>] i915_pci_probe+0x35/0x60 [i915]
[<c070321f>] pci_device_probe+0x6f/0xc0
[<c05ea3d5>] ? sysfs_create_link+0x25/0x40
[<c07ce733>] driver_probe_device+0x93/0x3a0
[<c05ea107>] ? sysfs_create_dir_ns+0x37/0x80
[<c0703161>] ? pci_match_device+0xc1/0xe0
[<c07ceaf1>] __driver_attach+0x71/0x80
[<c07cea80>] ? __device_attach+0x40/0x40
[<c07ccb67>] bus_for_each_dev+0x57/0xa0
[<c07ce25e>] driver_attach+0x1e/0x20
[<c07cea80>] ? __device_attach+0x40/0x40
[<c07cdea7>] bus_add_driver+0x157/0x230
[<f8268000>] ? 0xf8267fff
[<f8268000>] ? 0xf8267fff
[<c07cf1d9>] driver_register+0x59/0xe0
[<c05777e6>] ? __kmalloc_track_caller+0x46/0x1f0
[<c0701d92>] __pci_register_driver+0x32/0x40
[<f7fcc0d5>] drm_pci_init+0xe5/0x110 [drm]
[<f8268000>] ? 0xf8267fff
[<f8268088>] i915_init+0x88/0x8a [i915]
[<f8268000>] ? 0xf8267fff
[<c0402132>] do_one_initcall+0xc2/0x1f0
[<f8268000>] ? 0xf8267fff