Ubuntu
linux package

Can't switch display mode more than one cycle when docked

  1. Trusty (14.04)
  2. Bug #1416451
Bug #1416451 reported by Timo Aaltonen
6
This bug affects 1 person
Affects Status Importance Assigned to Milestone
linux (Ubuntu)
Invalid
Undecided
Timo Aaltonen
Declined for Utopic by Kamal Mostafa
Trusty
Fix Released
Undecided
Unassigned

Bug Description

[Impact]
We have a system under certification that needs a workaround in the kernel for now. The bug is that if the machine is booted attached to a dock with a monitor connected to it's VGA output, the connection to the monitor is dropped after one full cycle of display modes with the hotkey combo. This is a firmware bug and will eventually be fixed by the BIOS vendor, but in the meantime we need a workaround in the kernel.

The dock has a builtin DP-VGA dongle which is the culprit here.

[Test Case]
attach the unit to a doc with a monitor plugged to a VGA port, switch display modes with hotkey combo, should be able to do more than one cycle with the combo

[Regression Potential]
We got the patch from Intel, with this disclaimer:
"The workaround in comment 41# maybe has side effect on DP port which doesn't connect DP screen. On these DP ports, this workaround will add an extra power on and power off command . So this workaround couldn't push to upstream."

so there shouldn't be any visible regressions..

CVE References

Timo Aaltonen (tjaalton)
affects: xorg (Ubuntu) → linux (Ubuntu)
Changed in linux (Ubuntu):
assignee: nobody → Timo Aaltonen (tjaalton)
status: New → Triaged
Brad Figg (brad-figg)
Changed in linux (Ubuntu):
status: Triaged → Fix Committed
Andy Whitcroft (apw)
Changed in linux (Ubuntu Trusty):
status: New → Fix Committed
Revision history for this message
Brad Figg (brad-figg) wrote :

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-trusty' to 'verification-done-trusty'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

tags: added: verification-needed-trusty
Timo Aaltonen (tjaalton)
tags: added: verification-done-trusty
removed: verification-needed-trusty
Revision history for this message
Launchpad Janitor (janitor) wrote :
Download full text (12.8 KiB)

This bug was fixed in the package linux - 3.13.0-46.75

---------------
linux (3.13.0-46.75) trusty; urgency=low

  [ Seth Forshee ]

  * Release Tracking Bug
    - LP: #1419963

  [ Andy Whitcroft ]

  * [Debian] arm64 -- build ubuntu drivers
    - LP: #1411284
  * hyper-v -- fix comment handing in /etc/network/interfaces
    - LP: #1413020

  [ Kamal Mostafa ]

  * [Packaging] force "dpkg-source -I -i" behavior

  [ Upstream Kernel Changes ]

  * Revert "[SCSI] mpt2sas: Remove phys on topology change."
    - LP: #1419838
  * Revert "[SCSI] mpt3sas: Remove phys on topology change"
    - LP: #1419838
  * Btrfs: fix transaction abortion when remounting btrfs from RW to RO
    - LP: #1411320
  * Btrfs: fix a crash of clone with inline extents's split
    - LP: #1413129
  * net/mlx4_en: Add VXLAN ndo calls to the PF net device ops too
    - LP: #1407760
  * KVM: x86: SYSENTER emulation is broken
    - LP: #1414651
    - CVE-2015-0239
  * powerpc/xmon: Fix another endiannes issue in RTAS call from xmon
    - LP: #1415919
  * ipv6: fix swapped ipv4/ipv6 mtu_reduced callbacks
    - LP: #1404558, #1419837
  * usb: gadget: at91_udc: move prepare clk into process context
    - LP: #1419837
  * KVM: x86: Fix far-jump to non-canonical check
    - LP: #1419837
  * x86/tls: Validate TLS entries to protect espfix
    - LP: #1419837
  * userns: Check euid no fsuid when establishing an unprivileged uid
    mapping
    - LP: #1419837
  * userns: Document what the invariant required for safe unprivileged
    mappings.
    - LP: #1419837
  * userns: Only allow the creator of the userns unprivileged mappings
    - LP: #1419837
  * x86_64, switch_to(): Load TLS descriptors before switching DS and ES
    - LP: #1419837
  * isofs: Fix infinite looping over CE entries
    - LP: #1419837
  * batman-adv: Calculate extra tail size based on queued fragments
    - LP: #1419837
  * KEYS: close race between key lookup and freeing
    - LP: #1419837
  * isofs: Fix unchecked printing of ER records
    - LP: #1419837
  * x86_64, vdso: Fix the vdso address randomization algorithm
    - LP: #1419837
  * groups: Consolidate the setgroups permission checks
    - LP: #1419837
  * userns: Don't allow setgroups until a gid mapping has been setablished
    - LP: #1419837
  * userns: Don't allow unprivileged creation of gid mappings
    - LP: #1419837
  * move d_rcu from overlapping d_child to overlapping d_alias
    - LP: #1419837
  * deal with deadlock in d_walk()
    - LP: #1419837
  * Linux 3.13.11-ckt14
    - LP: #1419837
  * gre: fix the inner mac header in nbma tunnel xmit path
    - LP: #1419838
  * netlink: Always copy on mmap TX.
    - LP: #1419838
  * netlink: Don't reorder loads/stores before marking mmap netlink frame
    as available
    - LP: #1419838
  * in6: fix conflict with glibc
    - LP: #1419838
  * tg3: tg3_disable_ints using uninitialized mailbox value to disable
    interrupts
    - LP: #1419838
  * batman-adv: Unify fragment size calculation
    - LP: #1419838
  * batman-adv: avoid NULL dereferences and fix if check
    - LP: #1419838
  * net: Fix stacked vlan offload features computation
    - LP: #1419838
  * net: Reset secmark when scrubbing packet
    - L...

Changed in linux (Ubuntu Trusty):
status: Fix Committed → Fix Released
Mathew Hodson (mhodson)
Changed in linux (Ubuntu):
status: Fix Committed → Invalid
To post a comment you must log in.
This report contains Public information  
Everyone can see this information.
Subscribing...

Other bug subscribers

Remote bug watches

Bug watches keep track of this bug in other bug trackers.