Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.

RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Description of problem:
I have some troubles to recover all 3 monitors (one of secondary ones - connected via DP through docking station) after going to mirror mode and back in gnome display settings. I just get black screen. Monitor is on. I can recover via turning it off and on again in g-d-p.

I have some screenshots (attached)    

Version-Release number of selected component (if applicable):
00:02.0 VGA compatible controller [0300]: Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09)
kernel-2.6.32-347.el6.x86_64
xorg-x11-drv-intel-2.20.2-2.el6.x86_64
xorg-x11-server-Xorg-1.13.0-8.el6.x86_64


How reproducible:
100%

Steps to Reproduce:
1.attach two more screens to your docking station with laptop lid open
2.go to g-d-p and set all 3 side-by-side
3.go to g-d-p and select mirror
3.go back to side-by-side setup
  
Actual results:
one of the external minotors is blank

Expected results:
all 3 should come up

Additional info:

Created attachment 676332 [details]
both screens black but turned on

Created attachment 676333 [details]
just the second one after mirror disabling

reproducer to the first picture:
1. switch to second user
2. set all 3 screens with different resolution than in first case
3. swicth back to firts user via alt+F7 

two external screens are blank.

Created attachment 676334 [details]
xorg log

Vladimir, what different modes where you using (modeline best, but resolution + refresh rate probably good enough).  IVB has some limitations when it comes to triple display.  In particular two of the displays need to have the same clock.  See:

https://github.com/eugeni/ivb_mode_calc

btw, output of xrandr cmd would also be useful

The important information here is in a drm.debug=6 dmesg, which should explain why the modeset failed. Why the two modesetting sequences were different is an artifact of userspace.

Putting into needinfo to get the information requested by Rob and Chris.

I'm not able to reproduce with 

xorg-x11-drv-intel-2.21.12-1.el6.x86_64
xorg-x11-server-Xorg-1.13.0-16.el6.x86_64
kernel -405

Closing as CURRENTRELEASE.

Tom