Bug 1374828

Summary: Display dimension regression
Product: [Fedora] Fedora Reporter: fedora_account
Component: kernelAssignee: Kernel Maintainer List <kernel-maint>
Status: CLOSED CURRENTRELEASE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 25CC: fedora_account, gansalmon, ichavero, itamar, jonathan, kernel-maint, labbott, madhu.chinakonda, mchehab
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: If docs needed, set a value
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Clone Of: Environment:
Last Closed: 2017-02-06 17:01:53 UTC Type: Bug
Regression: --- Mount Type: ---
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Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Attachments:
Description Flags
Xorg.0.log
none
dmesg
none
modetest -M i915
none
dmsg with drm.debug=0xf
none
dmsg_4.8.0-0.rc8 with drm.debug=0xf none

Description fedora_account 2016-09-09 18:31:09 UTC
Created attachment 1199588 [details]
Xorg.0.log

Description of problem:

Display dimension is incorrectly determined in Fedora25-Alpha2, but was being correctly determined in Fedora24.

Version-Release number of selected component (if applicable):

This problem has been observed in these isos,
  Fedora-Workstation-Live-x86_64-25_Alpha-2.iso
  Fedora-Xfce-Live-x86_64-25_Alpha-2.iso
  Fedora-Xfce-Live-x86_64-25-20160909.n.0.iso


How reproducible:

Repeatable


Steps to Reproduce:
1. Boot from usb stick, or boot after a full installation.

Actual results:

An incorrect display dimension of 1280x600 is recognized.  This display dimension is used during bootup text display and is also used by the X11 (both Gnome and Xfce).


Expected results:

The correct display dimension of 1280x800 should be recognized.


Additional info:

1. Hardware is a Sony PCG-5K1L notebook.
2. Fedora 24 (Fedora-Xfce-Live-x86_64-24-1.2.iso) correctly picks up display as 1280x800 on this hardware.
3. The problem is reproducible both with a live disk and after a bare-metal installation.

Comment 1 fedora_account 2016-09-09 18:33:49 UTC
Created attachment 1199589 [details]
dmesg

Comment 2 fedora_account 2016-09-12 11:36:20 UTC
On further investigation, we see that this problem can also be observed with Fedora 24.

1. do a fresh install of Fedora24 and notice that we have correctly recognized the 1280x800 display dimension, while using kernel 4.5.5-300.

2. do `dnf update kernel` to bring in the 4.7.2-201 kernel and reboot.  Then notice that we have incorrect 1280x600 display dimension and we now have a kernel stack dump in the dmesg log implicating the i915 driver.

Comment 3 fedora_account 2016-09-12 16:46:09 UTC
Digging a little deeper we find that this problem first appears with kernel-4.7.2-201.fc24.  We also notice however that earlier versions of the F24 kernel also generated stack dumps in the dmesg log during boot (see attached dmesg).

Here are the results of our tests:

kernel-4.5.5-300.fc24: no stack dump, correct display dimension
kernel-4.5.6-300.fc24: no stack dump, correct display dimension
kernel-4.5.7-300.fc24: no stack dump, correct display dimension

kernel-4.6.3-300.fc24: stack dump, correct display dimension
kernel-4.6.4-301.fc24: stack dump, correct display dimension
kernel-4.6.5-300.fc24: stack dump, correct display dimension
kernel-4.6.6-300.fc24: stack dump, correct display dimension
kernel-4.6.7-300.fc24: stack dump, correct display dimension

kernel-4.7.2-201.fc24: stack dump, wrong display dimension

Comment 4 fedora_account 2016-09-17 15:03:36 UTC
Created attachment 1201973 [details]
modetest -M i915

The results of `modetest -M i915` are attached.  Note that the i915 driver is reporting an incorrect display dimension of 1280x600.

Comment 5 fedora_account 2016-09-19 06:32:23 UTC
Created attachment 1202313 [details]
dmsg with drm.debug=0xf

With kernel 4.8.0-0.rc6 and the kernel parameter drm.debug=0xf.

Comment 6 fedora_account 2016-09-29 14:20:51 UTC
Created attachment 1205956 [details]
dmsg_4.8.0-0.rc8  with drm.debug=0xf

This problem is fixed in kernel-4.8.0-0.rc8.git0.1.fc25.x86_64.  The correct display dimension is now being picked up.  See attached dmesg_4.8.0-0.rc8.log

Comment 7 Laura Abbott 2017-01-17 01:24:33 UTC
*********** MASS BUG UPDATE **************
We apologize for the inconvenience.  There is a large number of bugs to go through and several of them have gone stale.  Due to this, we are doing a mass bug update across all of the Fedora 25 kernel bugs.
 
Fedora 25 has now been rebased to 4.9.3-200.fc25.  Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel.
 
If you have moved on to Fedora 26, and are still experiencing this issue, please change the version to Fedora 26.
 
If you experience different issues, please open a new bug report for those.

Comment 8 fedora_account 2017-02-06 16:04:26 UTC
This problem is fixed in the current Fedora 25 kernel.