Bug 904232

Summary: DRM_UDL: drm/kms driver(udl.ko) for the DisplayLink devices - PASSED
Product: [Fedora] Fedora Reporter: poma <pomidorabelisima>
Component: kernelAssignee: Dave Airlie <airlied>
Status: CLOSED CURRENTRELEASE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: urgent Docs Contact:
Priority: unspecified    
Version: 18CC: airlied, bigbeerjr, gansalmon, itamar, jonathan, kernel-maint, madhu.chinakonda, pir8don, schaiba, tcallawa, thomas.mey, zbyszek
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2013-02-09 20:58:52 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description poma 2013-01-25 19:49:20 UTC 
Device description:
DisplayLink DL-165 based device
Overfly FY-1016A USB-DVI graphics adapter[1][2][3][4][5]
lsusb:
Bus 002 Device 002: ID 17e9:019e DisplayLink
dmesg:
usb 2-1: New USB device found, idVendor=17e9, idProduct=019e
usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 2-1: Product: FY USB-DVI
usb 2-1: Manufacturer: DisplayLink
usb 2-1: SerialNumber: USB_FY1704

Kernel ring buffer output:
drm/udl/nouveau dmesg:
[drm] Initialized drm 1.1.0 20060810
[drm] venouveaundor descriptor length:1b data:1b 5f 01 00 19 05 00 01 03 00 04
fb: conflicting fb hw usage nouveaufb vs VESA VGA - removing generic driver
Console: switching
to colour dummy device 80x25
Raw EDID:
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
usb 2-1: DVI-I-1: EDID invalid.
open /dev/fb0 user=0 fb_info=ffff880122d74000 count=1
[drm] write mode info 153
Console: switching to colour frame buffer device 128x48
fb0: udldrmfb frame buffer device
drm: registered panic notifier
[drm] Initialized udl 0.0.1 20120220 on minor 0
usbcore: registered new interface driver udl
nouveau  [  DEVICE][0000:02:00.0] BOOT0  : 0x098200a2
nouveau  [  DEVICE][0000:02:00.0] Chipset: G98 (NV98)
nouveau  [  DEVICE][0000:02:00.0] Family : NV50
nouveau  [   VBIOS][0000:02:00.0] checking PRAMIN for image...
nouveau  [   VBIOS][0000:02:00.0] ... appears to be valid
nouveau  [   VBIOS][0000:02:00.0] using image from PRAMIN
nouveau  [   VBIOS][0000:02:00.0] BIT signature found
nouveau  [   VBIOS][0000:02:00.0] version 62.98.2c.00
nouveau  [     MXM][0000:02:00.0] no VBIOS data, nothing to do
nouveau  [     PFB][0000:02:00.0] RAM type: DDR2
nouveau  [     PFB][0000:02:00.0] RAM size: 512 MiB
[TTM] Zone  kernel: Available graphics memory: 2024360 kiB
[TTM] Initializing pool allocator
[TTM] Initializing DMA pool allocator
nouveau  [     DRM] VRAM: 512 MiB
nouveau  [     DRM] GART: 512 MiB
nouveau  [     DRM] BIT BIOS found
nouveau  [     DRM] Bios version 62.98.2c.00
nouveau  [     DRM] TMDS table version 2.0
nouveau  [     DRM] DCB version 4.0
nouveau  [     DRM] DCB outp 00: 02000300 00000028
nouveau  [     DRM] DCB outp 01: 01000302 00020030
nouveau  [     DRM] DCB outp 02: 04011310 00000028
nouveau  [     DRM] DCB outp 03: 010223f1 00c0c080
nouveau  [     DRM] DCB conn 00: 00001030
nouveau  [     DRM] DCB conn 01: 00000100
nouveau  [     DRM] DCB conn 02: 00000210
nouveau  [     DRM] DCB conn 03: 00000211
nouveau  [     DRM] DCB conn 04: 00000213
nouveau W[     DRM] DCB encoder 1 unknown
nouveau W[     DRM] TV-1 has no encoders, removing
[drm] Supports vblank timestamp caching Rev 1 (10.10.2010).
[drm] No driver support for vblank timestamp query.
nouveau  [     DRM] 1 available performance level(s)
nouveau  [     DRM] 3: core 567MHz shader 1400MHz memory 400MHz fanspeed 100%
nouveau  [     DRM] c: core 566MHz shader 1400MHz memory 399MHz
nouveau  [     DRM] MM: using M2MF for buffer copies
nouveau  [     DRM] allocated 1024x768 fb: 0x60000, bo ffff88012334a800
fbcon: nouveaufb (fb1) is primary device
fbcon: Remapping primary device, fb1, to tty 1-63
released /dev/fb0 user=0 count=0
fb1: nouveaufb frame buffer device
[drm] Initialized nouveau 1.1.0 20120801 for 0000:02:00.0 on minor 1
open /dev/fb0 user=1 fb_info=ffff880122d74000 count=1
released /dev/fb0 user=1 count=0
Raw EDID:
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
usb 2-1: DVI-I-1: EDID invalid.
Raw EDID:
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
usb 2-1: DVI-I-1: EDID invalid.
[drm] write mode info 153
Raw EDID:
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
usb 2-1: DVI-I-1: EDID invalid.
Raw EDID:
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
usb 2-1: DVI-I-1: EDID invalid.
Raw EDID:
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
usb 2-1: DVI-I-1: EDID invalid.
Adjusting tsc more than 11% (5832478 vs 5819596)
fuse init (API version 7.20)
SELinux: initialized (dev fuse, type fuse), uses genfs_contexts
SELinux: initialized (dev fusectl, type fusectl), uses genfs_contexts
Raw EDID:
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
usb 2-1: DVI-I-1: EDID invalid.
Raw EDID:
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
usb 2-1: DVI-I-1: EDID invalid.
open /dev/fb0 user=1 fb_info=ffff880122d74000 count=1
released /dev/fb0 user=1 count=0
…
When connected monitor(VGA) get activated with e.g.
xfce4-display-settings[6][7][8] picture is garbled[9][10],
and nouveau emerge(dmesg):
[drm] write mode info 153
[drm] write mode info 153
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
…
The system gets almost unresponsive.

Xorg - X11R7 X server output:
/var/log/Xorg.0.log:
…
(EE) modesetting(G0): Unknown EDID version 0
reporting 3 3 45 354
have a master to look out for
adjust shatters 0 1920
need to create shared pixmap 1reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
…

RandR extension output:
xrandr:
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192
DVI-I-2 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 531mm x 299mm
   1920x1080      60.0*+   50.0  
   1920x1080i     25.0     30.0  
   1600x1200      60.0  
   1680x1050      59.9  
   1680x945       60.0  
   1400x1050      59.9  
   1600x900       60.0  
   1280x1024      75.0     60.0  
   1440x900       75.0     59.9  
   1280x960       60.0  
   1366x768       60.0  
   1360x768       60.0  
   1280x800       74.9     59.9  
   1152x864       75.0  
   1280x768       74.9     60.0  
   1280x720       50.0     60.0  
   1024x768       75.1     70.1     60.0  
   1024x576       60.0  
   832x624        74.6  
   800x600        72.2     75.0     60.3     56.2  
   720x576        50.0  
   848x480        60.0  
   720x480        59.9  
   640x480        72.8     75.0     66.7     60.0  
   720x400        70.1  
VGA-1 disconnected (normal left inverted right x axis y axis)
DVI-0 connected
   1024x768       60.0  
   800x600        60.3     56.2  
   848x480        60.0  
   640x480        59.9  
  1024x768 (0x42)   65.0MHz
        h: width  1024 start 1048 end 1184 total 1344 skew    0 clock   48.4KHz
        v: height  768 start  771 end  777 total  806           clock   60.0Hz
  800x600 (0x43)   40.0MHz
        h: width   800 start  840 end  968 total 1056 skew    0 clock   37.9KHz
        v: height  600 start  601 end  605 total  628           clock   60.3Hz
  800x600 (0x44)   36.0MHz
        h: width   800 start  824 end  896 total 1024 skew    0 clock   35.2KHz
        v: height  600 start  601 end  603 total  625           clock   56.2Hz
  848x480 (0x45)   33.8MHz
        h: width   848 start  864 end  976 total 1088 skew    0 clock   31.0KHz
        v: height  480 start  486 end  494 total  517           clock   60.0Hz
…


With edid loading through kernel boot parameter(drm_kms_helper.edid_firmware=DVI-I-1:edid/848-480)
i.e. /lib/firmware/edid/848-480
monitor-parse-edid /lib/firmware/edid/848-480:
Name: WVGA 848
EISA ID: JCX0701
EDID version: 1.3
EDID extension blocks: 0
Screen size: 15.6 cm x 8.8 cm (7.05 inches, aspect ratio 16/9 = 1.77)
Gamma: 2.2
Analog signal
Max video bandwidth: 40 MHz

	HorizSync 30-32
	VertRefresh 59-61

	# Monitor preferred modeline (60.0 Hz vsync, 31.0 kHz hsync, ratio 1.77, 138 dpi)
	ModeLine "848x480" 33.75 848 864 976 1088 480 486 494 517 +hsync +vsync
…
dmesg is:
vesafb: mode is 800x600x32, linelength=3200, pages=0
vesafb: scrolling: redraw
vesafb: Truecolor: size=8:8:8:8, shift=24:16:8:0
vesafb: framebuffer at 0xf7000000, mapped to 0xffffc90003000000, using 1920k, total 1920k
Console: switching to colour frame buffer device 100x37
fb0: VESA VGA frame buffer device
usb 2-1: New USB device found, idVendor=17e9, idProduct=019e
usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 2-1: Product: FY USB-DVI
usb 2-1: Manufacturer: DisplayLink
usb 2-1: SerialNumber: USB_FY1704
[drm] Initialized drm 1.1.0 20060810
[drm] vendor descriptor length:1b data:1b 5f 01 00 19 05 00 01 03 00 04
[Fri Jan 25 18:24:58 2013] fb: conflicting fb hw usage nouveaufb vs VESA VGA - removing generic driver
…
At this moment system boot stalling.
…
Console: switching 
to colour dummy device 80x25
…
System boot resuming after ~ 1 minute.
…
[Fri Jan 25 18:25:59 2013] [drm:edid_load] *ERROR* Requesting EDID firmware "edid/848-480" failed (err=-2)
Raw EDID:
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
usb 2-1: DVI-I-1: EDID invalid.
open /dev/fb0 user=0 fb_info=ffff880123352800 count=1
[drm] write mode info 153
Console: switching to colour frame buffer device 128x48
fb0: udldrmfb frame buffer device
drm: registered panic notifier
[drm] Initialized udl 0.0.1 20120220 on minor 0
usbcore: registered new interface driver udl
nouveau  [  DEVICE][0000:02:00.0] BOOT0  : 0x098200a2
nouveau  [  DEVICE][0000:02:00.0] Chipset: G98 (NV98)
nouveau  [  DEVICE][0000:02:00.0] Family : NV50
nouveau  [   VBIOS][0000:02:00.0] checking PRAMIN for image...
nouveau  [   VBIOS][0000:02:00.0] ... appears to be valid
nouveau  [   VBIOS][0000:02:00.0] using image from PRAMIN
nouveau  [   VBIOS][0000:02:00.0] BIT signature found
nouveau  [   VBIOS][0000:02:00.0] version 62.98.2c.00
nouveau  [     MXM][0000:02:00.0] no VBIOS data, nothing to do
nouveau  [     PFB][0000:02:00.0] RAM type: DDR2
nouveau  [     PFB][0000:02:00.0] RAM size: 512 MiB
[TTM] Zone  kernel: Available graphics memory: 2024360 kiB
[TTM] Initializing pool allocator
[TTM] Initializing DMA pool allocator
nouveau  [     DRM] VRAM: 512 MiB
nouveau  [     DRM] GART: 512 MiB
nouveau  [     DRM] BIT BIOS found
nouveau  [     DRM] Bios version 62.98.2c.00
nouveau  [     DRM] TMDS table version 2.0
nouveau  [     DRM] DCB version 4.0
nouveau  [     DRM] DCB outp 00: 02000300 00000028
nouveau  [     DRM] DCB outp 01: 01000302 00020030
nouveau  [     DRM] DCB outp 02: 04011310 00000028
nouveau  [     DRM] DCB outp 03: 010223f1 00c0c080
nouveau  [     DRM] DCB conn 00: 00001030
nouveau  [     DRM] DCB conn 01: 00000100
nouveau  [     DRM] DCB conn 02: 00000210
nouveau  [     DRM] DCB conn 03: 00000211
nouveau  [     DRM] DCB conn 04: 00000213
nouveau W[     DRM] DCB encoder 1 unknown
nouveau W[     DRM] TV-1 has no encoders, removing
[drm] Supports vblank timestamp caching Rev 1 (10.10.2010).
[drm] No driver support for vblank timestamp query.
nouveau  [     DRM] 1 available performance level(s)
nouveau  [     DRM] 3: core 567MHz shader 1400MHz memory 400MHz fanspeed 100%
nouveau  [     DRM] c: core 566MHz shader 1400MHz memory 399MHz
nouveau  [     DRM] MM: using M2MF for buffer copies
nouveau  [     DRM] allocated 1024x768 fb: 0x60000, bo ffff8801221f1800
fbcon: nouveaufb (fb1) is primary device
fbcon: Remapping primary device, fb1, to tty 1-63
released /dev/fb0 user=0 count=0
fb1: nouveaufb frame buffer device
[drm] Initialized nouveau 1.1.0 20120801 for 0000:02:00.0 on minor 1
open /dev/fb0 user=1 fb_info=ffff880123352800 count=1
released /dev/fb0 user=1 count=0
[Fri Jan 25 18:26:23 2013] [drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
…
Edid is finally loaded.
After that monitor is powered on and picture is garbled[11].
At login screen monitor is powered on BUT visually in blank mode!?
…
[drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
[drm] write mode info 153
[drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
[drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
[drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
[drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
[drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
…

monitor-parse-edid /sys/class/drm/card0-DVI-I-1/edid 
Name: WVGA 848
EISA ID: JCX0701
EDID version: 1.3
EDID extension blocks: 0
Screen size: 15.6 cm x 8.8 cm (7.05 inches, aspect ratio 16/9 = 1.77)
Gamma: 2.2
Analog signal
Max video bandwidth: 40 MHz

	HorizSync 30-32
	VertRefresh 59-61

	# Monitor preferred modeline (60.0 Hz vsync, 31.0 kHz hsync, ratio 1.77, 138 dpi)
	ModeLine "848x480" 33.75 848 864 976 1088 480 486 494 517 +hsync +vsync
…
Edid loading is successfull, although w/ 1 minute stalling

Not every EDID/module loading is successfully :|:
…
nouveau E[     DRM] no native mode, forcing panel scaling
[drm] wait for urb interrupted: ffffffc2 available: 4
[drm] wait for urb interrupted: ffffffc2 available: 4
[drm] wait for urb interrupted: ffffffc2 available: 4
general protection fault: 0000 [#1] SMP 
Modules linked in: …
CPU 0 
Pid: 1840, comm: Xorg Tainted: …
RIP: 0010:[<ffffffffa019e1b3>]  [<ffffffffa019e1b3>] nouveau_gem_unmap_dma_buf+0x33/0x70 [nouveau]
RSP: 0018:ffff880127b57c58  EFLAGS: 00010293
RAX: 7961727400000013 RBX: ffff8800aef1bc20 RCX: 0000000000000000
RDX: 0000000000000800 RSI: ffff88009cec4000 RDI: ffff880122bf5088
RBP: ffff880127b57c68 R08: 0000000000000000 R09: ffff88012b002700
R10: ffffffff81cdc490 R11: 0000000000000001 R12: ffff8801212df020
R13: ffff8801212df000 R14: 0000000000000003 R15: ffff880127b57d30
FS:  00007ff79f21f940(0000) GS:ffff88012fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00007f40df842504 CR3: 00000001210aa000 CR4: 00000000000007f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process Xorg (pid: 1840, threadinfo ffff880127b56000, task ffff880125ad1720)
Stack:
ffff8800ad928d80 ffff8800c8538040 ffff880127b57c78 ffffffff813e03f2
ffff880127b57c98 ffffffffa0099c4b ffff8800ad928d80 ffff8801212df020
ffff880127b57cb8 ffffffffa0049bc9 ffff880127b57cc8 ffff8800ad928d80
Call Trace:
[<ffffffff813e03f2>] dma_buf_unmap_attachment+0x22/0x40
[<ffffffffa0099c4b>] drm_prime_gem_destroy+0x2b/0x50 [drm]
[<ffffffffa0049bc9>] udl_gem_free_object+0x39/0x70 [udl]
[<ffffffffa008399a>] drm_gem_object_free+0x2a/0x30 [drm]
[<ffffffffa0083cf8>] drm_gem_object_release_handle+0xa8/0xd0 [drm]
[<ffffffff812e76e9>] idr_for_each+0x89/0xe0
[<ffffffffa0083c50>] ? drm_gem_vm_close+0x80/0x80 [drm]
[<ffffffffa0084744>] drm_gem_release+0x24/0x40 [drm]
[<ffffffffa0082e12>] drm_release+0x542/0x5e0 [drm]
[<ffffffff811aa69d>] ? d_kill+0xbd/0x110
[<ffffffff8119665c>] __fput+0xec/0x240
[<ffffffff811967be>] ____fput+0xe/0x10
[<ffffffff8107e995>] task_work_run+0xc5/0xe0
[<ffffffff810641d1>] do_exit+0x191/0x8b0
[<ffffffff81633be6>] ? __schedule+0x3c6/0x7a0
[<ffffffff81064c2f>] do_group_exit+0x3f/0xa0
[<ffffffff81064ca7>] sys_exit_group+0x17/0x20
[<ffffffff8163dad9>] system_call_fastpath+0x16/0x1b
Code: 48 89 e5 53 48 89 f3 48 83 ec 08 48 8b 7f 08 8b 56 08 48 8b 36 48 85 ff 74 3e 48 8b 87 10 02 00 00 48 85 c0 74 32 83 f9 02 77 36 <48> 8b 40 38 48 85 c0 74 05 45 31 c0 ff d0 48 89 df e8 87 88 15 
RIP  [<ffffffffa019e1b3>] nouveau_gem_unmap_dma_buf+0x33/0x70 [nouveau]
RSP <ffff880127b57c58>
 ---[ end trace 6d8a129856995b61 ]---
Fixing recursive fault but reboot is needed!
…

[drm:edid_load] *ERROR* Requesting EDID firmware "edid/848-480" failed (err=-2)
[drm:udl_get_edid] *ERROR* Read EDID byte 0 failed err ffffffb9
BUG: unable to handle kernel NULL pointer dereference at 000000000000007e
IP: [<ffffffffa01358ef>] udl_get_modes+0x11f/0x1a0 [udl]
PGD 0 
Oops: 0000 [#1] SMP 
Modules linked in: nouveau(+) raid1 mxm_wmi video i2c_algo_bit ttm udl(+) drm_usb …drm_kms_helper …
CPU 1 
Pid: 220, comm: systemd-udevd Not tainted 3.7.2-204.fc18.x86_64 #1 Gigabyte Technology Co., Ltd. M720-US3/M720-US3
RIP: 0010:[<ffffffffa01358ef>]  [<ffffffffa01358ef>] udl_get_modes+0x11f/0x1a0 [udl]
RSP: 0018:ffff880122843a98  EFLAGS: 00010202
RAX: ffff880129401101 RBX: 0000000000000000 RCX: 0000000000000273
RDX: 0000000000000272 RSI: 0000000000000046 RDI: ffff8801294011c0
RBP: ffff880122843ae8 R08: 00000000000169c0 R09: 00000000000003be
R10: 0766076607200772 R11: 0772076507200764 R12: 0000000000000000
R13: ffff8801228fb808 R14: ffff880122ebe800 R15: ffff8801294011c0
FS:  00007ff807487840(0000) GS:ffff88012fc40000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000007e CR3: 0000000122fa8000 CR4: 00000000000007e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process systemd-udevd (pid: 220, threadinfo ffff880122842000, task ffff880122978000)
Stack:
ffff8801294011c0 0000000000000002 00000000000003e8 0000000000000000
ffff8801228fb800 ffff880122ebeac8 0000000000000000 ffff8801228ff800
ffff880122ebe800 0000000000000800 ffff880122843b38 ffffffffa00c2711
Call Trace:
drm_helper_probe_single_connector_modes+0x2c1/0x340 [drm_kms_helper]
[<ffffffffa00bfee0>] drm_fb_helper_probe_connector_modes.isra.2+0x50/0x70 [drm_kms_helper]
[<ffffffffa00c1523>] drm_fb_helper_initial_config+0x1a3/0x230 [drm_kms_helper]
[<ffffffff8118047f>] ? kmem_cache_alloc_trace+0x12f/0x160
[<ffffffffa0136ffc>] udl_fbdev_init+0x8c/0xc0 [udl]
[<ffffffffa01360ec>] udl_driver_load+0x2bc/0x490 [udl]
[<ffffffffa0077244>] drm_get_usb_dev+0x154/0xf10 [drm_usb]
[<ffffffff813dee80>] ? __pm_runtime_set_status+0x140/0x210
[<ffffffffa0135065>] udl_usb_probe+0x15/0x20 [udl]
[<ffffffff814520b1>] usb_probe_interface+0x1b1/0x2b0
[<ffffffff813d309b>] driver_probe_device+0x8b/0x390
[<ffffffff813d344b>] __driver_attach+0xab/0xb0
[<ffffffff813d33a0>] ? driver_probe_device+0x390/0x390
[<ffffffff813d1125>] bus_for_each_dev+0x55/0x90
[<ffffffff813d2a0e>] driver_attach+0x1e/0x20
[<ffffffff813d2640>] bus_add_driver+0x1a0/0x290
[<ffffffff813d3b17>] driver_register+0x77/0x170
[<ffffffff8145095d>] usb_register_driver+0x8d/0x160
[<ffffffffa00770d9>] drm_usb_init+0x79/0x90 [drm_usb]
[<ffffffffa013d000>] ? 0xffffffffa013cfff
[<ffffffffa013d017>] udl_init+0x17/0x1000 [udl]
[<ffffffff8100216a>] do_one_initcall+0x12a/0x180
[<ffffffff810c2a10>] sys_init_module+0xc0/0x220
[<ffffffff8163ded9>] system_call_fastpath+0x16/0x1b
Code: c1 89 da 48 c7 c6 28 87 13 a0 48 c7 c7 fe 81 13 a0 31 c0 e8 44 16 f5 ff 4c 89 e7 45 31 e4 e8 49 9d 04 e1 4c 89 ff e8 41 9d 04 e1 <41> 0f b6 44 24 7e 4c 89 e6 4c 89 f7 41 00 44 24 7f 41 c6 44 24 
RIP  [<ffffffffa01358ef>] udl_get_modes+0x11f/0x1a0 [udl]
RSP <ffff880122843a98>
CR2: 000000000000007e
---[ end trace 8ee5f5e0213fe5fd ]---
…

[drm:edid_load] *ERROR* Requesting EDID firmware "edid/848-480" failed (err=-2)
[drm:udl_get_edid] *ERROR* Read EDID byte 0 failed err ffffffed
BUG: unable to handle kernel NULL pointer dereference at 000000000000007e
IP: [<ffffffffa00f48ef>] udl_get_modes+0x11f/0x1a0 [udl]
PGD 0 
Oops: 0000 [#1] SMP 
Modules linked in: udl(+) drm_usb …
etc. etc. etc.

Btw /etc/modprobe.d/drm_kms_helper.conf:
options drm_kms_helper edid_firmware=edid/edid-848-480
has no effect as kernel boot parameter has!?

Someone might wonder, why all this fuzziness with EDID.
Well, connected monitor in this particular setup is 7" LCD with VGA connector,
unfortunately with broken EDID or no EDID at all.

I have to say something - multiseat with udlfb.ko(DisplayLink kernel framebuffer driver) worked
like a charm in Fedora 17!
Thanks to all devs for hard work - past 'n future!

Version-Release number of selected component (if applicable):
3.7.2-204.fc18.x86_64 SMP mod_unload

[1] http://en.overflye.com/english/list.asp?id=2543
[2] http://goo.gl/ujmDB
[3] http://goo.gl/T3CGb
[4] http://goo.gl/r9TXl
[5] http://goo.gl/E67Iy
[6] http://goo.gl/crouu
[7] http://goo.gl/yIUE7
[8] http://goo.gl/L8H6q
[9] http://goo.gl/cXQmr
[10] http://goo.gl/fNUiW
[11] http://goo.gl/sTIzr
Comment 1 Don 2013-01-29 08:17:34 UTC 
I have similar problems with this chipset running kernel 3.7.4-204.fc18.x86_64
since upgrading from 3.7.2 have now got an edid but still with fast flashing and although the device now shows in seat-status I cannot attach to a seat.

[  419.559042] usb 1-7: new high-speed USB device number 10 using ehci_hcd
[  419.676935] usb 1-7: New USB device found, idVendor=17e9, idProduct=0198
[  419.676944] usb 1-7: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[  419.676950] usb 1-7: Product: WS Tech USB-DVI
[  419.676955] usb 1-7: Manufacturer: DisplayLink
[  419.676960] usb 1-7: SerialNumber: 511409
[  419.681732] [drm] vendor descriptor length:23 data:23 5f 01 00 21 00 04 04 07 00 01
[  419.762936] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 56
[  419.762944] Raw EDID:
[  419.762950]      00 ff ff ff ff ff ff 00 01 0c 18 08 d0 d5 05 00
[  419.762953]      16 0d 01 03 1f 22 1b 78 ea c5 c6 a3 57 4a 9c 23
[  419.762957]      01 d0 54 bf ef 80 71 4a 71 4f 81 40 81 80 01 01
[  419.762961]      01 01 01 01 01 01 30 2a c8 ff ff c8 7f 40 30 fe
[  419.762965]      01 00 52 0e 11 00 00 1e 00 00 00 ff 00 20 42 5a
[  419.762968]      20 20 33 38 32 34 31 36 0a 20 00 00 00 fc 00 50
[  419.762972]      68 69 6c 69 70 73 20 31 37 30 53 34 00 00 00 fd
[  419.762976]      00 38 4c 1e 52 0e 00 0a b0 ff ff 90 20 20 00 ff
[  419.762985] usb 1-7: DVI-I-2: EDID invalid.
[  419.766128] fb2: udldrmfb frame buffer device
[  419.766146] [drm] Initialized udl 0.0.1 20120220 on minor 2
[  419.889569] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 56
[  419.889577] Raw EDID:
[  419.889583]      00 ff ff ff ff ff ff 00 01 0c 18 08 d0 d5 05 00
[  419.889587]      16 0d 01 03 1f 22 1b 78 ea c5 c6 a3 57 4a 9c 23
[  419.889591]      01 d0 54 bf ef 80 71 4a 71 4f 81 40 81 80 01 01
[  419.889595]      01 01 01 01 01 01 30 2a c8 ff ff c8 7f 40 30 fe
[  419.889598]      01 00 52 0e 11 00 00 1e 00 00 00 ff 00 20 42 5a
[  419.889602]      20 20 33 38 32 34 31 36 0a 20 00 00 00 fc 00 50
[  419.889606]      68 69 6c 69 70 73 20 31 37 30 53 34 00 00 00 fd
[  419.889610]      00 38 4c 1e 52 0e 00 0a b0 ff ff 90 20 20 00 ff
[  419.889620] usb 1-7: DVI-I-2: EDID invalid.
[  419.971072] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 56
[  419.971079] Raw EDID:
[  419.971085]      00 ff ff ff ff ff ff 00 01 0c 18 08 d0 d5 05 00
[  419.971089]      16 0d 01 03 1f 22 1b 78 ea c5 c6 a3 57 4a 9c 23
[  419.971093]      01 d0 54 bf ef 80 71 4a 71 4f 81 40 81 80 01 01
[  419.971097]      01 01 01 01 01 01 30 2a c8 ff ff c8 7f 40 30 fe
[  419.971100]      01 00 52 0e 11 00 00 1e 00 00 00 ff 00 20 42 5a
[  419.971104]      20 20 33 38 32 34 31 36 0a 20 00 00 00 fc 00 50
[  419.971108]      68 69 6c 69 70 73 20 31 37 30 53 34 00 00 00 fd
[  419.971112]      00 38 4c 1e 52 0e 00 0a b0 ff ff 90 20 20 00 ff
[  419.971121] usb 1-7: DVI-I-2: EDID invalid.
[  419.997979] [drm] write mode info 153
[  478.462573] SELinux: initialized (dev proc, type proc), uses genfs_contexts

Does this bug apply to all devices with the DL165 chipset? I thought it was used in the most common multiseat devices.
Comment 2 poma 2013-01-29 10:11:14 UTC 
(In reply to comment #1)
> I have similar problems with this chipset running kernel
> 3.7.4-204.fc18.x86_64
> since upgrading from 3.7.2 have now got an edid but still with fast flashing
> and although the device now shows in seat-status I cannot attach to a seat.
[…]
> Does this bug apply to all devices with the DL165 chipset? I thought it was
> used in the most common multiseat devices.

Heya,

See these links:
http://lists.freedesktop.org/archives/systemd-devel/2013-January/008287.html
https://bugzilla.redhat.com/show_bug.cgi?id=877183
https://bugzilla.redhat.com/show_bug.cgi?id=892389
Comment 3 poma 2013-01-29 10:14:14 UTC 
[…]
gdm-binary & gnome-shell
3.7.4-204.fc18.x86_64

xrandr -q
Screen 0: minimum 320 x 200, current 2944 x 1080, maximum 8192 x 8192
DVI-I-2 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 531mm x 299mm
   1920x1080      60.0*+   50.0  
   1920x1080i     25.0     30.0  
   1600x1200      60.0  
   1680x1050      59.9  
   1680x945       60.0  
   1400x1050      59.9  
   1600x900       60.0  
   1280x1024      75.0     60.0  
   1440x900       75.0     59.9  
   1280x960       60.0  
   1366x768       60.0  
   1360x768       60.0  
   1280x800       74.9     59.9  
   1152x864       75.0  
   1280x768       74.9     60.0  
   1280x720       50.0     60.0  
   1024x768       75.1     70.1     60.0  
   1024x576       60.0  
   832x624        74.6  
   800x600        72.2     75.0     60.3     56.2  
   720x576        50.0  
   848x480        60.0  
   720x480        59.9  
   640x480        72.8     75.0     66.7     60.0  
   720x400        70.1  
VGA-1 disconnected (normal left inverted right x axis y axis)
DVI-0 connected 1024x768+1920+0 0mm x 0mm
   1024x768       60.0* 
   800x600        60.3     56.2  
   848x480        60.0  
   640x480        59.9  
  1024x768 (0x42)   65.0MHz
        h: width  1024 start 1048 end 1184 total 1344 skew    0 clock   48.4KHz
        v: height  768 start  771 end  777 total  806           clock   60.0Hz
  800x600 (0x43)   40.0MHz
        h: width   800 start  840 end  968 total 1056 skew    0 clock   37.9KHz
        v: height  600 start  601 end  605 total  628           clock   60.3Hz
  800x600 (0x44)   36.0MHz
        h: width   800 start  824 end  896 total 1024 skew    0 clock   35.2KHz
        v: height  600 start  601 end  603 total  625           clock   56.2Hz
  848x480 (0x45)   33.8MHz
        h: width   848 start  864 end  976 total 1088 skew    0 clock   31.0KHz
        v: height  480 start  486 end  494 total  517           clock   60.0Hz

/var/log/Xorg.0.log
…
(==) Matched fbdev as autoconfigured driver 6
(II) LoadModule: "fbdev"
(II) Loading /usr/lib64/xorg/modules/drivers/fbdev_drv.so
(II) Module fbdev: vendor="X.Org Foundation"
(II) FBDEV: driver for framebuffer: fbdev
(WW) Falling back to old probe method for fbdev
(II) Loading sub module "fbdevhw"
(II) LoadModule: "fbdevhw"
(II) Loading /usr/lib64/xorg/modules/libfbdevhw.so
(II) Module fbdevhw: vendor="X.Org Foundation"
…
(II) Loading sub module "fb"
(II) LoadModule: "fb"
(II) Loading /usr/lib64/xorg/modules/libfb.so
(II) Module fb: vendor="X.Org Foundation"
(II) Loading sub module "shadowfb"
(II) LoadModule: "shadowfb"
(II) Loading /usr/lib64/xorg/modules/libshadowfb.so
(II) Module shadowfb: vendor="X.Org Foundation"
(II) modesetting(G0): ShadowFB: preferred NO, enabled NO
(II) Loading sub module "fb"
(II) LoadModule: "fb"
(II) Loading /usr/lib64/xorg/modules/libfb.so
(II) Module fb: vendor="X.Org Foundation"
(II) UnloadModule: "fbdev"
(II) Unloading fbdev
(II) UnloadSubModule: "fbdevhw"
(II) Unloading fbdevhw
…
(II) NOUVEAU(0): Modeline "1440x576i"x0.0   27.00  1440 1464 1590 1728  576 580 586 625 interlace -hsync -vsync (15.6 kHz e)
(EE) modesetting(G0): Unknown EDID version 0
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
reporting 3 3 45 354
(EE)
(EE) Backtrace:
(EE) 0: /usr/bin/Xorg (xorg_backtrace+0x36) [0x46c466]
(EE) 1: /usr/bin/Xorg (0x400000+0x71d99) [0x471d99]
(EE) 2: /lib64/libpthread.so.0 (0x31a9e00000+0xf000) [0x31a9e0f000]
(EE) 3: /usr/bin/Xorg (RRCrtcDetachScanoutPixmap+0x52) [0x50a392]
(EE) 4: /usr/bin/Xorg (0x400000+0x10a4c8) [0x50a4c8]
(EE) 5: /usr/bin/Xorg (0x400000+0x5c0c2) [0x45c0c2]
(EE) 6: /usr/bin/Xorg (FreeClientResources+0x95) [0x45d265]
(EE) 7: /usr/bin/Xorg (FreeAllResources+0x47) [0x45d317]
(EE) 8: /usr/bin/Xorg (0x400000+0x280fe) [0x4280fe]
(EE) 9: /lib64/libc.so.6 (__libc_start_main+0xf5) [0x31a9621a05]
(EE) 10: /usr/bin/Xorg (0x400000+0x28411) [0x428411]
(EE) 
(EE) Segmentation fault at address 0x418

Fatal server error:
Caught signal 11 (Segmentation fault). Server aborting

(EE)
Please consult the Fedora Project support
	 at http://wiki.x.org
 for help.
(EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
(EE)
(II) AIGLX: Suspending AIGLX clients for VT switch
(II) NOUVEAU(0): NVLeaveVT is called.
Server terminated with error (1). Closing log file.
…

dmesg
Raw EDID:
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
usb 2-1: DVI-I-1: EDID invalid.
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
nouveau E[     DRM] fail set_domain
nouveau E[     DRM] validate gart_list
nouveau E[     DRM] validate: -22
…


With /etc/X11/xorg.conf

=======================================================
xorg-x11-drv-displaylink-0-7.20110102git.fc17.x86_64  <==
===========================================================

xorg.conf
Section "Device"
        Identifier      "Videocard0"
        Driver          "nouveau"
EndSection

Section "Device"
        Identifier      "dl0"
========================================
        driver          "displaylink"  <==
============================================
        Option  "fbdev" "/dev/fb1"
EndSection
…

/var/log/Xorg.0.log

X.Org X Server 1.13.1
Release Date: 2012-12-13
X Protocol Version 11, Revision 0
…
Build Date: 09 January 2013  03:42:52AM
Build ID: xorg-x11-server 1.13.1-4.fc18 
…
(II) LoadModule: "displaylink"
(II) Loading /usr/lib64/xorg/modules/drivers/displaylink_drv.so
(II) Module displaylink: vendor="X.Org Foundation"
    compiled for 1.11.99.901, module version = 0.0.1
    ABI class: X.Org Video Driver, version 12.0
=============================================================================
(EE) module ABI major version (12) doesn't match the server's version (13)  <==
=================================================================================
(II) UnloadModule: "displaylink"
(II) Unloading displaylink
(EE) Failed to load module "displaylink" (module requirement mismatch, 0)
(II) LoadModule: "nouveau"
(II) Loading /usr/lib64/xorg/modules/drivers/nouveau_drv.so
(II) Module nouveau: vendor="X.Org Foundation"
    compiled for 1.13.0, module version = 1.0.6
    Module class: X.Org Video Driver
    ABI class: X.Org Video Driver, version 13.0
…


Information for package xorg-x11-drv-displaylink
http://koji.fedoraproject.org/koji/packageinfo?packageID=12371

Information for build xorg-x11-drv-displaylink-0-8.20110102git.fc18
http://koji.fedoraproject.org/koji/buildinfo?buildID=343333
=================
State 	failed  <==
=====================

Bug 57264 - xf86-video-displaylink-0.3 driver no longer works after the last update
https://bugs.freedesktop.org/show_bug.cgi?id=57264


With 'IgnoreABI'

/var/log/Xorg.0.log
…
(**) Option "IgnoreABI" "True"
…
(II) LoadModule: "displaylink"
(II) Loading /usr/lib64/xorg/modules/drivers/displaylink_drv.so
(II) Module displaylink: vendor="X.Org Foundation"
 	compiled for 1.11.99.901, module version = 0.0.1
 	ABI class: X.Org Video Driver, version 12.0
(WW) module ABI major version (12) doesn't match the server's version (13)
…
(II) DL: driver for : displaylink
(++) using VT number 1

(WW) Falling back to old probe method for displaylink
(II) Loading sub module "fbdevhw"
(II) LoadModule: "fbdevhw"
(II) Loading /usr/lib64/xorg/modules/libfbdevhw.so
(II) Module fbdevhw: vendor="X.Org Foundation"
 	compiled for 1.13.1, module version = 0.0.2
 	ABI class: X.Org Video Driver, version 13.1
(II) DL(0): using /dev/fb1
(II) [drm] nouveau interface version: 1.1.0
(EE) DL(0): Unknown EDID version 129
(II) DL(0): Creating default Display subsection in Screen section
	"screen0" for depth/fbbpp 8/8
(==) DL(0): Depth 8, (==) framebuffer bpp 8
(==) DL(0): Default visual is PseudoColor
(==) DL(0): Using gamma correction (1.0, 1.0, 1.0)
(II) DL(0): hardware: udldrmfb (video memory: 768kB)
(**) DL(0): Option "fbdev" "/dev/fb1"
(II) Loading sub module "fb"
(II) LoadModule: "fb"
(II) Loading /usr/lib64/xorg/modules/libfb.so
(II) Module fb: vendor="X.Org Foundation"
 	compiled for 1.13.1, module version = 1.0.0
 	ABI class: X.Org ANSI C Emulation, version 0.4
(II) DL(0): Output udldrmfb using monitor section monitor1
(EE) DL(0): Unknown EDID version 33
(II) DL(0): EDID for output udldrmfb
(EE)
(EE) Backtrace:
(EE) 0: /usr/bin/Xorg (xorg_backtrace+0x36) [0x46c466]
(EE) 1: /usr/bin/Xorg (0x400000+0x71d99) [0x471d99]
(EE) 2: /lib64/libpthread.so.0 (0x31a9e00000+0xf000) [0x31a9e0f000]
(EE) 3: /usr/lib64/xorg/modules/drivers/displaylink_drv.so (0x7f1a3c261000+0x3b04) [0x7f1a3c264b04]
(EE) 4: /usr/bin/Xorg (InitOutput+0xa09) [0x48da09]
(EE) 5: /usr/bin/Xorg (0x400000+0x27ed6) [0x427ed6]
(EE) 6: /lib64/libc.so.6 (__libc_start_main+0xf5) [0x31a9621a05]
(EE) 7: /usr/bin/Xorg (0x400000+0x28411) [0x428411]
(EE)
(EE) Segmentation fault at address 0x24

Fatal server error:
Caught signal 11 (Segmentation fault). Server aborting
 
(EE) 
Please consult the Fedora Project support
	 at http://wiki.x.org
 for help.
(EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
(EE) 
Server terminated with error (1). Closing log file.
--

Probably the same story
https://bugzilla.redhat.com/show_bug.cgi?id=877183
https://bugzilla.redhat.com/show_bug.cgi?id=892389
Comment 4 Thomas Meyer 2013-02-01 17:14:04 UTC 
Please remove the drm_udl driver from the fedora config. It's broken. Please enable udlfb instead!

See: 
http://plugable.com/2012/06/21/displaylink-usb-devices-on-linux-kernel-3-4-0/comment-page-1#comment-5896
Comment 5 poma 2013-02-01 20:29:43 UTC 
The average user will surely be lost. Anyway there is a solution, but not on a platter, although relatively simple.

diff /boot/config-3.7.4-204.fc18.x86_64 /boot/config-3.7.5-101.fc18.x86_64 | grep 'FB\|UDL'
< CONFIG_DRM_UDL=m
> # CONFIG_DRM_UDL is not set
< # CONFIG_FB_MODE_HELPERS is not set
> CONFIG_FB_MODE_HELPERS=y
< # CONFIG_FB_UDL is not set
> CONFIG_FB_UDL=m

3.7.4-204.fc18.x86_64 is the official Fedora 18 version, on the other hand 3.7.5-101.fc18.x86_64 is recompiled Fedora 17 version. See the Koji[1].

uname -r
3.7.5-101.fc18.x86_64

There are a bunch of instructions on how to do it[2], e.g. MultiseatX[2].
I'll give a brief example of how I did it with the help of the LightDM[3].
/etc/lightdm/lightdm.conf:
…
[Seat:0]
xserver-command=/usr/bin/Xorg :0 -auth /var/run/lightdm/root/:0
xserver-config=/etc/X11/xorg.conf.Nvidia

[Seat:1]
xserver-command=/usr/bin/Xorg :1 -auth /var/run/lightdm/root/:1 -novtswitch -sharevts
xserver-config=/etc/X11/xorg.conf.DisplayLink
autologin-user=koji
…

ps:
… tty7 … /usr/bin/Xorg :0 -auth /var/run/lightdm/root/:0 :0 -config /etc/X11/xorg.conf.Nvidia -auth /var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch
… tty8 … /usr/bin/Xorg :1 -auth /var/run/lightdm/root/:1 -novtswitch -sharevts :1 -config /etc/X11/xorg.conf.DisplayLink -auth /var/run/lightdm/root/:1 -nolisten tcp vt8 -novtswitch

'-novtswitch' is a bit redundant since been engaged by the 'lightdm'. Whatever :)
The most important option is '-sharevts' on all seats except the primary one.
One can use '/usr/lib/systemd/systemd-multi-seat-x[4]' with embedded 'ServerFlags' and 'InputClass'
xorg.conf.Nvidia/DisplayLink are straightforward.
And it's more or less all ;)


[1] 
http://koji.fedoraproject.org/koji/packageinfo?packageID=8
[2] https://help.ubuntu.com/community/MultiseatX
[3] https://launchpad.net/lightdm/
[4] http://cgit.freedesktop.org/systemd/systemd/tree/src/login/multi-seat-x.c
Comment 6 Don 2013-02-01 22:09:26 UTC 
"The average user will surely be lost." - I think that must be me! 

Certainly a reversion to the udflib seems prudent until the  new drivers stabilise.

I can't find 3.7.5-101.fc18.x86_64 anywhere on the Koji link. I see the fc17. 

Can I simply install that rpm on fc18 and have the old drivers in place of the new?

I am using gnome so do I understand correctly that I don't need to make any changes there?

Thanks for your help

Don
Comment 7 poma 2013-02-02 09:04:52 UTC 
(In reply to comment #6)
[…]
> I can't find 3.7.5-101.fc18.x86_64 anywhere on the Koji link. I see the
> fc17. 
> 

3.7.5-101.fc18.x86_64 is recompiled Fedora 17 version, I've made for personal use ;)

> Can I simply install that rpm on fc18 and have the old drivers in place of
> the new?
> 

Surely,
rpm -ivh http://kojipkgs.fedoraproject.org//packages/kernel/3.7.5/101.fc17/x86_64/kernel-3.7.5-101.fc17.x86_64.rpm

> I am using gnome so do I understand correctly that I don't need to make any
> changes there?
> 

If you just upgrade the kernel, it will end as
/var/log/Xorg.1.log:
…
(II) LoadModule: "fbdev"
(II) Loading /usr/lib64/xorg/modules/drivers/fbdev_drv.so
(II) Module fbdev: vendor="X.Org Foundation"
	compiled for 1.12.99.902, module version = 0.4.3
	Module class: X.Org Video Driver
	ABI class: X.Org Video Driver, version 13.0
(II) VESA: driver for VESA chipsets: vesa
(II) FBDEV: driver for framebuffer: fbdev
(--) using VT number 1

(EE) No devices detected.

Fatal server error:
no screens found
(EE) 
Please consult the Fedora Project support 
	 at http://wiki.x.org
 for help. 
(EE) Please also check the log file at "/var/log/Xorg.1.log" for additional information.
(EE) 
--

You have to go straight with the above mentioned settings(display manager & Xorg).
IMHO LightDM is the simplest and fastest approach.
See the systemd's DRM transitions[1][2][3].

[1] http://cgit.freedesktop.org/systemd/systemd/log/?qt=grep&q=multi-seat
[2] http://cgit.freedesktop.org/systemd/systemd/commit/?id=ec29187225c0b404f6b9f59a416c4fa0c0afaaff
[3] http://cgit.freedesktop.org/systemd/systemd/commit/?id=e57d4fa35ece7c506e6ed16bb245591252143f9c
Comment 8 Don 2013-02-02 09:13:02 UTC 
Thanks Poma
Comment 9 poma 2013-02-07 16:13:06 UTC 
(In reply to comment #8)
> Thanks Poma

Cheers ;)
Comment 10 poma 2013-02-07 16:16:31 UTC 
In the end, it was a zen riddle :)
Thank you airlied!

http://koji.fedoraproject.org/koji/buildinfo?buildID=382431

Changelog

* Wed Feb 06 2013 Dave Airlie <airlied> 1.0.6-4
 - fixup one fix to avoid crashes in some cases
* Wed Feb 06 2013 Dave Airlie <airlied> 1.0.6-3
  ==> - update to latest upstream - fixes USB offload  <==

rpm -Uvh http://kojipkgs.fedoraproject.org//packages/xorg-x11-drv-nouveau/1.0.6/4.fc18/x86_64/xorg-x11-drv-nouveau-1.0.6-4.fc18.x86_64.rpm

The only remaining issues(3) are:
- edid loading lag(~ 1 minute)
- not effective modprobe module's option
Unlike kernel's boot parameter, /etc/modprobe.d/drm_kms_helper.conf:
options drm_kms_helper edid_firmware=DVI-I-1:edid/848-480
actually has no effect.
- broken 'displaylink_drv.so'
Actually the one that is used is 'fbdev_drv.so'(xorg-x11-drv-fbdev) Xorg X11 fbdev video driver, so what exactly do we get from 'displaylink_drv.so' anyway!?

dmesg:
[… 11:51:15 …] Kernel command line: BOOT_IMAGE=/vmlinuz-3.7.5-201.fc18.x86_64 … drm_kms_helper.edid_firmware=DVI-I-1:edid/848-480
…
[… 11:51:18 …] usb 1-6: new high-speed USB device number 6 using ehci_hcd
…
[… 11:51:18 …] usb 1-6: New USB device found, idVendor=17e9, idProduct=019e
[… 11:51:18 …] usb 1-6: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[… 11:51:18 …] usb 1-6: Product: FY USB-DVI
[… 11:51:18 …] usb 1-6: Manufacturer: DisplayLink
[… 11:51:18 …] usb 1-6: SerialNumber: USB_FY1704
…
[… 11:51:18 …] [drm] Initialized drm 1.1.0 20060810
[… 11:51:18 …] [drm] vendor descriptor length:1b data:1b 5f 01 00 19 05 00 01 03 00 04
…
  ==========================================================
  ==> SYSTEM BOOT STUMBLE ~ 1 minute(11:51:18 - 11:52:18 ) <==
  ==============================================================
…
[… 11:52:18 …] [drm:edid_load] *ERROR* Requesting EDID firmware "edid/848-480" failed (err=-2)
[… 11:52:19 …] Raw EDID:
[… 11:52:19 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 11:52:19 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 11:52:19 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 11:52:19 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 11:52:19 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 11:52:19 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 11:52:19 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 11:52:19 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 11:52:19 …] usb 1-6: DVI-I-1: EDID invalid.
[… 11:52:19 …] fb1: udldrmfb frame buffer device
[… 11:52:19 …] drm: registered panic notifier
[… 11:52:19 …] [drm] Initialized udl 0.0.1 20120220 on minor 0
[… 11:52:19 …] usbcore: registered new interface driver udl
…
[… 11:52:44 …] [drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
[… 11:52:44 …] [drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
[… 11:52:44 …] [drm] write mode info 153
…
[… 11:52:48 …] [drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
[… 11:52:48 …] [drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
…
[… 11:52:53 …] [drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
…
[… 11:56:22 …] [drm] Got external EDID base block and 0 extensions from "edid/848-480" for connector "DVI-I-1"
…
--

monitor-parse-edid /sys/class/drm/card0-DVI-I-1/edid:
Name: Linux WVGA
EDID version: 1.3
EDID extension blocks: 0
Screen size: 22.0 cm x 12.5 cm (9.96 inches, aspect ratio 16/9 = 1.76)
Gamma: 2.2
Analog signal
Max video bandwidth: 40 MHz

	HorizSync 30-32
	VertRefresh 59-61

	# Monitor preferred modeline (60.0 Hz vsync, 31.0 kHz hsync, ratio 1.77, 97 dpi)
	ModeLine "848x480" 33.75 848 864 976 1088 480 486 494 517 +hsync +vsync
--

Actual EDID modeline template with proper(sic) geometry for this particular monitor
/usr/share/doc/kernel-doc-3.7.5/Documentation/EDID/848x480.S:
/*
   848x480.S: EDID data set for standard 848x480 60 Hz monitor

   Copyright (C) 2012 Carsten Emde <C.Emde>

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation; either version 2
   of the License, or (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA.
*/

/* EDID */
#define VERSION 1
#define REVISION 3

/* Display */
#define CLOCK 33750 /* kHz */
#define XPIX 848
#define YPIX 480
#define XY_RATIO XY_RATIO_16_9
#define XBLANK 240
#define YBLANK 37
#define XOFFSET 16
#define XPULSE 112
#define YOFFSET (63+6)
#define YPULSE (63+8)
#define DPI 96
#define VFREQ 60 /* Hz */
#define TIMING_NAME "Linux WVGA"
#define ESTABLISHED_TIMINGS_BITS 0x00 /* none */
#define HSYNC_POL 1
#define VSYNC_POL 1
#define CRC 0x96

#include "edid.S"
--

EXTENDED display/s is/are *working* and is/are configurable via corresponding DE's display/s settings modules, 
i.e. 'xfce4-display-settings'(XFCE), 'systemsettings'(KDE), 'gnome-control-center'(GNOME) and
via xrandr:
Disables the output
xrandr --output DVI-0 --off
Enables the output
xrandr --output DVI-0 [--auto| --mode 848x480]
…
man xrandr 1
--

MULTISEAT
I noticed a little bit different behavior than in Fedora 17 setup.
With /etc/udev/rules.d/72-persistent-seat.rules:
#  This is a custom udev rule file in addition to systemd's /usr/lib/udev/rules.d/71-seat.rules

ACTION=="remove", GOTO="seat_end"

TAG=="uaccess", SUBSYSTEM!="sound", TAG+="seat"
SUBSYSTEM=="sound", KERNEL=="card*", TAG+="seat"
SUBSYSTEM=="input", KERNEL=="input*", TAG+="seat"
SUBSYSTEM=="graphics", KERNEL=="fb[0-9]*", TAG+="seat"
SUBSYSTEM=="usb", ATTR{bDeviceClass}=="09", TAG+="seat"

# Overfly FY-1016A USB-DVI graphics adapter
SUBSYSTEM=="graphics", ATTRS{idVendor}=="17e9", ATTRS{idProduct}=="019e", ENV{ID_AUTOSEAT}="1", ENV{ID_FOR_SEAT}="fy"
# udevadm info -a -p /sys/class/graphics/fb1

# Chicony KG-0609 Wireless Keyboard with integrated Touchpad and RG-0618U USB Wireless Receiver
SUBSYSTEM=="input", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ENV{ID_SEAT}="seat-fy"
# "seat-graphics-pci-0000_00_04_1-usb-0_2"  => "seat-fy"
# udevadm info -a -p /sys/class/input/mouse1

TAG=="seat", ENV{ID_PATH}=="", IMPORT{builtin}="path_id"
TAG=="seat", ENV{ID_FOR_SEAT}=="", ENV{ID_PATH_TAG}!="", ENV{ID_FOR_SEAT}="$env{SUBSYSTEM}-$env{ID_PATH_TAG}"

SUBSYSTEM=="input", ATTR{name}=="Wiebetech LLC Wiebetech", RUN+="/usr/bin/loginctl lock-sessions"

LABEL="seat_end"
--
it seems that ENV{ID_AUTOSEAT}="1" has no effect at all, i.e. multiseat is not set automatically via systemd/udev.
So what I did was manually attaching devices:
loginctl attach seat-fy \
/sys/devices/pci0000:00/0000:00:04.1/usb1/1-6/drm/card0 \
/sys/devices/pci0000:00/0000:00:04.0/usb2/2-9/2-9:1.0/input/input5 \
/sys/devices/pci0000:00/0000:00:04.0/usb2/2-9/2-9:1.0/input/input6 \
/sys/devices/pci0000:00/0000:00:04.0/usb2/2-9/2-9:1.1/input/input7 \
/sys/devices/pci0000:00/0000:00:04.0/usb2/2-9/2-9:1.1/input/input8 \
/sys/devices/pci0000:00/0000:00:04.0/usb2/2-9/2-9:1.1/input/input9 \
/sys/devices/pci0000:00/0000:00:04.0/usb2/2-9/2-9:1.2/input/input10
--
and thus have generated:
- /etc/udev/rules.d/72-seat-drm-pci-0000_00_04_1-usb-0_6.rules:
TAG=="seat", ENV{ID_FOR_SEAT}=="drm-pci-0000_00_04_1-usb-0_6", ENV{ID_SEAT}="seat-fy"
- /etc/udev/rules.d/72-seat-input-pci-0000_00_04_0-usb-0_9_1_0.rules:
TAG=="seat", ENV{ID_FOR_SEAT}=="input-pci-0000_00_04_0-usb-0_9_1_0", ENV{ID_SEAT}="seat-fy"
- /etc/udev/rules.d/72-seat-input-pci-0000_00_04_0-usb-0_9_1_1.rules:
TAG=="seat", ENV{ID_FOR_SEAT}=="input-pci-0000_00_04_0-usb-0_9_1_1", ENV{ID_SEAT}="seat-fy"
- /etc/udev/rules.d/72-seat-input-pci-0000_00_04_0-usb-0_9_1_2.rules:
TAG=="seat", ENV{ID_FOR_SEAT}=="input-pci-0000_00_04_0-usb-0_9_1_2", ENV{ID_SEAT}="seat-fy"
--
systemctl restart gdm.service
From this point on everything went automatically, finally :)

ps x | grep X:
… ?    … /usr/bin/Xorg :0 -background none -verbose -auth /var/run/gdm/auth-for-gdm-kPUDvK/database -seat seat0 -nolisten tcp vt1
… tty1 … /usr/bin/X :1 -background none -verbose -auth /var/run/gdm/auth-for-gdm-5OiwgM/database -seat seat-fy -nolisten tcp -config /run/systemd/multi-session-x/seat-fy -sharevts
--

loginctl list-seats:
SEAT
seat0
seat-fy

2 seats listed.
--

loginctl seat-status seat-fy:
seat-fy
        Sessions: *4
         Devices:
                  ├─/sys/devices/pci0000:00/0000:00:04.0/usb2/2-9/2-9:1.0/input/input5
                  │ (input:input5) "Chicony USB Wireless HID Receiver"
                  ├─/sys/devices/pci0000:00/0000:00:04.0/usb2/2-9/2-9:1.0/input/input6
                  │ (input:input6) "Chicony USB Wireless HID Receiver"
                  ├─/sys/devices/pci0000:00/0000:00:04.0/usb2/2-9/2-9:1.1/input/input7
                  │ (input:input7) "Chicony USB Wireless HID Receiver"
                  ├─/sys/devices/pci0000:00/0000:00:04.0/usb2/2-9/2-9:1.1/input/input8
                  │ (input:input8) "Chicony USB Wireless HID Receiver"
                  ├─/sys/devices/pci0000:00/0000:00:04.0/usb2/2-9/2-9:1.1/input/input9
                  │ (input:input9) "Chicony USB Wireless HID Receiver"
                  ├─/sys/devices/pci0000:00/0000:00:04.0/usb2/2-9/2-9:1.2/input/input10
                  │ (input:input10) "Chicony USB Wireless HID Receiver"
                  ├─/sys/devices/pci0000:00/0000:00:04.1/usb1/1-6/drm/card0
                  │ (drm:card0)
                  └─/sys/devices/pci0000:00/0000:00:04.1/usb1/1-6/graphics/fb1
                    (graphics:fb1) "udldrmfb"
--

loginctl show-seat seat-fy:
Id=seat-fy
ActiveSession=4
CanMultiSession=no
CanTTY=no
CanGraphical=yes
Sessions=4
IdleHint=no
IdleSinceHint=0
IdleSinceHintMonotonic=0
--

/run/systemd/multi-session-x/seat-fy:
Section "ServerFlags"
        Option "AutoAddDevices" "True"
        Option "AllowEmptyInput" "True"
        Option "DontVTSwitch" "True"
EndSection
Section "InputClass"
        Identifier "Force Input Devices to Seat"
        Option "GrabDevice" "True"
EndSection
--

/var/log/Xorg.1.log:
…
 (II) config/udev: Adding drm device (/dev/dri/card0)
…
 (II) LoadModule: "modesetting"
 (II) Loading /usr/lib64/xorg/modules/drivers/modesetting_drv.so
 (II) Module modesetting: vendor="X.Org Foundation"
 	compiled for 1.13.0, module version = 0.6.0
 	Module class: X.Org Video Driver
 	ABI class: X.Org Video Driver, version 13.0
 (II) LoadModule: "fbdev"
 (II) Loading /usr/lib64/xorg/modules/drivers/fbdev_drv.so
 (II) Module fbdev: vendor="X.Org Foundation"
 	compiled for 1.12.99.902, module version = 0.4.3
 	Module class: X.Org Video Driver
 	ABI class: X.Org Video Driver, version 13.0
…
 (II) modesetting: Driver for Modesetting Kernel Drivers: kms
 (II) FBDEV: driver for framebuffer: fbdev
 (--) using VT number 1
…
 (II) modesetting(0): using drv /dev/dri/card0
 (II) modesetting(0): Creating default Display subsection in Screen section
	"Default Screen Section" for depth/fbbpp 24/32
 (==) modesetting(0): Depth 24, (==) framebuffer bpp 32
 (==) modesetting(0): RGB weight 888
 (==) modesetting(0): Default visual is TrueColor
 (II) modesetting(0): ShadowFB: preferred NO, enabled NO
 (II) modesetting(0): Output DVI-0 has no monitor section
 (II) modesetting(0): EDID for output DVI-0
 (II) modesetting(0): Manufacturer: LNX  Model: 0  Serial#: 0
 (II) modesetting(0): Year: 2012  Week: 5
 (II) modesetting(0): EDID Version: 1.3
 (II) modesetting(0): Analog Display Input,  Input Voltage Level: 0.700/0.700 V
 (II) modesetting(0): Sync:  Separate  CompositeSerration on. V.Sync Pulse req. if CompSync or SyncOnGreen
 (II) modesetting(0): Max Image Size : horiz.: 22  vert.: 12
 (II) modesetting(0): Gamma: 2.20
 (II) modesetting(0): DPMS capabilities: StandBy Suspend Off; RGB/Color Display
 (II) modesetting(0): First detailed timing is preferred mode
 (II) modesetting(0): redX: 0.642 redY: 0.349   greenX: 0.292 greenY: 0.596
 (II) modesetting(0): blueX: 0.147 blueY: 0.125   whiteX: 0.312 whiteY: 0.328
 (II) modesetting(0): Manufacturer's mask: 0
 (II) modesetting(0): Supported standard timings:
 (II) modesetting(0): #0: hsize: 848  vsize 477  refresh: 60  vid: 49227
 (II) modesetting(0): Supported detailed timing:
 (II) modesetting(0): clock: 33.8 MHz   Image Size:  220 x 125 mm
 (II) modesetting(0): h_active: 848  h_sync: 864  h_sync_end 976 h_blank_end 1088 h_border: 0
 (II) modesetting(0): v_active: 480  v_sync: 486  v_sync_end 494 v_blanking: 517 v_border: 0
 (II) modesetting(0): Serial No: Linux #0
 (II) modesetting(0): Ranges: V min: 59 V max: 61 Hz, H min: 30 H max: 32 kHz, PixClock max 45 MHz
 (II) modesetting(0): Monitor name: Linux WVGA
 (II) modesetting(0): EDID (in hex):
 (II) modesetting(0): 	00ffffffffffff0031d8000000000000
 (II) modesetting(0): 	051601036d160c78ea5ec0a4594a9825
 (II) modesetting(0): 	2050540000004bc00101010101010101
 (II) modesetting(0): 	0101010101012f0d50f030e025101070
 (II) modesetting(0): 	6800dc7d0000001e000000ff004c696e
 (II) modesetting(0): 	75782023300a20202020000000fd003b
 (II) modesetting(0): 	3d1e2004000a202020202020000000fc
 (II) modesetting(0): 	004c696e757820575647410a20200096
 (II) modesetting(0): Printing probed modes for output DVI-0
 (II) modesetting(0): Modeline "848x480"x60.0   33.75  848 864 976 1088  480 486 494 517 +hsync +vsync (31.0 kHz eP)
 (II) modesetting(0): Modeline "848x477"x60.0   31.32  848 864 952 1056  477 478 481 494 -hsync +vsync (29.7 kHz)
 (II) modesetting(0): Modeline "640x480"x59.9   25.18  640 656 752 800  480 489 492 525 -hsync -vsync (31.5 kHz e)
 (II) modesetting(0): Output DVI-0 connected
 (II) modesetting(0): Using exact sizes for initial modes
 (II) modesetting(0): Output DVI-0 using initial mode 848x480 +0+0
 (II) modesetting(0): Using default gamma of (1.0, 1.0, 1.0) unless otherwise stated.
 (==) modesetting(0): DPI set to (96, 96)
 (II) Loading sub module "fb"
 (II) LoadModule: "fb"
 (II) Loading /usr/lib64/xorg/modules/libfb.so
 (II) Module fb: vendor="X.Org Foundation"
 	compiled for 1.13.2, module version = 1.0.0
 	ABI class: X.Org ANSI C Emulation, version 0.4
 (II) UnloadModule: "vesa"
 (II) Unloading vesa
 (II) UnloadModule: "fbdev"
 (II) Unloading fbdev
 (==) Depth 24 pixmap format is 32 bpp
 (==) modesetting(0): Backing store disabled
 (==) modesetting(0): Silken mouse enabled
 (II) modesetting(0): RandR 1.2 enabled, ignore the following RandR disabled message.
 (==) modesetting(0): DPMS enabled
 (--) RandR disabled
…
 (II) AIGLX: Screen 0 is not DRI2 capable
 (II) AIGLX: Screen 0 is not DRI capable
 (II) AIGLX: Loaded and initialized swrast
 (II) GLX: Initialized DRISWRAST GL provider for screen 0
 (II) modesetting(0): Damage tracking initialized
 (II) modesetting(0): Setting screen physical size to 224 x 127
…
 (II) config/udev: Adding drm device (/dev/dri/card0)
 (II) modesetting(0): EDID vendor "LNX", prod id 0
 (II) modesetting(0): Using EDID range info for horizontal sync
 (II) modesetting(0): Using EDID range info for vertical refresh
 (II) modesetting(0): Printing DDC gathered Modelines:
 (II) modesetting(0): Modeline "848x480"x0.0   33.75  848 864 976 1088  480 486 494 517 +hsync +vsync (31.0 kHz eP)
 (II) modesetting(0): Modeline "848x477"x60.0   31.30  848 864 952 1056  477 478 481 494 -hsync +vsync (29.6 kHz e)
…
--

xrandr -q:
xrandr -q
Screen 0: minimum 320 x 200, current 848 x 480, maximum 2048 x 2048
DVI-0 connected 848x480+0+0 220mm x 125mm
   848x480        60.0*+
   848x477        60.0  
   640x480        59.9  

--

It is important to note that there is a difference in naming device between kernel and X server,
linux: DVI-I-1
Xorg:  DVI-0
Comment 11 poma 2013-02-08 14:41:46 UTC 
(In reply to comment #10)
[…]
> - edid loading lag(~ 1 minute)

60 seconds edid loading lag is resolved[1].

[1] https://bugzilla.redhat.com/show_bug.cgi?id=901899#c16
Comment 12 poma 2013-02-09 05:14:26 UTC 
(In reply to comment #11)
[…]
> 60 seconds edid loading lag is resolved[1].
> 
> [1] https://bugzilla.redhat.com/show_bug.cgi?id=901899#c16

3.7.5-201 is actually an exception.

…
[… 05:09:22 …] Kernel command line: BOOT_IMAGE=/vmlinuz-3.7.6-201.fc18.x86_64 … drm_kms_helper.edid_firmware=DVI-I-1:edid/JC07-01-WVGA-848.edid
…
[… 05:09:24 …] usb 1-6: new high-speed USB device number 6 using ehci_hcd
[… 05:09:25 …] usb 1-6: New USB device found, idVendor=17e9, idProduct=019e
[… 05:09:25 …] usb 1-6: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[… 05:09:25 …] usb 1-6: Product: FY USB-DVI
[… 05:09:25 …] usb 1-6: Manufacturer: DisplayLink
[… 05:09:25 …] usb 1-6: SerialNumber: USB_FY1704
[… 05:09:25 …] [drm] Initialized drm 1.1.0 20060810
[… 05:09:25 …] [drm] vendor descriptor length:1b data:1b 5f 01 00 19 05 00 01 03 00 04
…
60 seconds boot lag after "Started udev Coldplug all Devices."
…
[… 05:10:25 …] [drm:edid_load] *ERROR* Requesting EDID firmware "edid/JC07-01-WVGA-848.edid" failed (err=-2)
[… 05:10:26 …] Raw EDID:
[… 05:10:26 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 05:10:26 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 05:10:26 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 05:10:26 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 05:10:26 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 05:10:26 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 05:10:26 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 05:10:26 …]  	00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 05:10:26 …] usb 1-6: DVI-I-1: EDID invalid.
[… 05:10:26 …] open /dev/fb0 user=0 fb_info=ffff880036e5f000 count=1
[… 05:10:26 …] [drm] write mode info 153
[… 05:10:26 …] Console: switching to colour frame buffer device 100x37
[… 05:10:26 …] fb0: udldrmfb frame buffer device
[… 05:10:26 …] drm: registered panic notifier
[… 05:10:26 …] [drm] Initialized udl 0.0.1 20120220 on minor 0
[… 05:10:26 …] usbcore: registered new interface driver udl
…
another 30 seconds…
…
[… 05:10:55 …] [drm] Got external EDID base block and 0 extensions from "edid/JC07-01-WVGA-848.edid" for connector "DVI-I-1"
[… 05:10:55 …] [drm] Got external EDID base block and 0 extensions from "edid/JC07-01-WVGA-848.edid" for connector "DVI-I-1"
[… 05:10:55 …] [drm] write mode info 153
[… 05:10:58 …] [drm] Got external EDID base block and 0 extensions from "edid/JC07-01-WVGA-848.edid" for connector "DVI-I-1"
[… 05:11:09 …] [drm] Got external EDID base block and 0 extensions from "edid/JC07-01-WVGA-848.edid" for connector "DVI-I-1"
…
Comment 13 poma 2013-02-09 20:58:52 UTC 
And the last goodbye :)

/etc/udev/rules.d/71-persistent-edid.rules:
#  This is a custom udev rule which engages a script after the device is added.
#
# Overfly FY-1016A USB-DVI graphics adapter
ACTION=="add", SUBSYSTEMS=="usb", ATTRS{idVendor}=="17e9", ATTRS{idProduct}=="019e", RUN+="/bin/edid-to-sys"
# udevadm info -a -p /sys/class/drm/card0
--

/bin/edid-to-sys
#!/bin/sh
# Via this script an EDID is specified on the fly via the 'sys' interface.
echo DVI-I-1:edid/JC07-01-WVGA-848.edid > /sys/module/drm_kms_helper/parameters/edid_firmware
--

…
[… 17:49:29 …] usb 1-6: New USB device found, idVendor=17e9, idProduct=019e
[… 17:49:29 …] usb 1-6: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[… 17:49:29 …] usb 1-6: Product: FY USB-DVI
[… 17:49:29 …] usb 1-6: Manufacturer: DisplayLink
[… 17:49:29 …] usb 1-6: SerialNumber: USB_FY1704
…
[… 17:49:29 …] [drm] Initialized drm 1.1.0 20060810
[… 17:49:29 …] [drm] vendor descriptor length:1b data:1b 5f 01 00 19 05 00 01 03 00 04
[… 17:49:29 …] Raw EDID:
[… 17:49:29 …]          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 17:49:29 …]          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 17:49:29 …]          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 17:49:29 …]          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 17:49:29 …]          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 17:49:29 …]          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 17:49:29 …]          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 17:49:29 …]          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[… 17:49:29 …] usb 1-6: DVI-I-1: EDID invalid.
[… 17:49:29 …] fb1: udldrmfb frame buffer device
[… 17:49:29 …] drm: registered panic notifier
[… 17:49:29 …] [drm] Initialized udl 0.0.1 20120220 on minor 0
[… 17:49:29 …] usbcore: registered new interface driver udl
…
=====
Where did this come from!? :))
This is one of the three connectors(DVI-D-1, HDMI-A-1, VGA-1) coupled on NV50(nouveau), none of DL-615(udl). :))
[… 17:50:04 …] [drm] Got external EDID base block and 0 extensions from "edid/JC07-01-WVGA-848.edid" for connector "VGA-1"
=============
[… 17:50:04 …] [drm] Got external EDID base block and 0 extensions from "edid/JC07-01-WVGA-848.edid" for connector "DVI-I-1"
[… 17:50:04 …] [drm] write mode info 153
[… 17:50:07 …] [drm] Got external EDID base block and 0 extensions from "edid/JC07-01-WVGA-848.edid" for connector "DVI-I-1"

[… 17:50:12 …] [drm] Got external EDID base block and 0 extensions from "edid/JC07-01-WVGA-848.edid" for connector "DVI-I-1"
…
--

Thanks goes to Carsten Emde.
https://www.osadl.org/monitoring/patches/r2s0/drivers-gpu-drm-allow-to-load-edid-firmware.patch

Cheers,
poma