Lenovo T530 has a green bar always exists on top of the screen, from initial boot to normal boot, from bootsplash to homescreen, always flashing.
| Affects | Status | Importance | Assigned to | Milestone | |
|---|---|---|---|---|---|
| Linux |
Fix Released
|
Medium
|
|||
| OEM Priority Project |
Invalid
|
Critical
|
Unassigned | ||
| linux (Ubuntu) |
Fix Released
|
Critical
|
Unassigned | ||
| Oneiric |
Fix Released
|
Critical
|
Timo Aaltonen | ||
Bug Description
SRU justification:
Impact:
Commit "628280f36e4fdbd drm/i915: Sanitize BIOS debugging bits from PIPECONF" got in the oneiric kernel via upstream, since it fixed a similar issue as here with an earlier version of the intel VBIOS. With a newer VBIOS however, the issue is back. Simply reverting the commit would likely mean breaking other setups.
this is a critical bug for some our OEM's
Fix:
upstream patch 3bcf603f6d5d18b from 3.1 works around a bug in the CPT/PPT PCH chips, and it was bisected as the commit that fixes the bug in 3.1 and up.
Testcase:
boot a kernel that doesn't have 3bcf603f6d5d18b but has 628280f36e4fdbd
on hw that has a "new enough" VBIOS.
--
Issue Description
-----------------
Garbage green lines (4-5 pixel lines) appear on top of some Lenovo laptops'
screens, persist from boot splash screen to desktop running.
Collected Data
--------------
Attached are the kernel dmesg, Xorg.0.log and dump files by intel_reg_dumper
for oneiric installation with kernel version 3.0.0-19.33 and 3.0.0-20.34, and
for precise installation with kernel version 3.2.0-23.26.
Observations
------------
2. This issue only happens on Oneiric with kernel version 3.0.0-20.34
and later ones
3. This issue does not happen on Oneiric with kernel version
3.0.0-19.33 and previous ones
4. This issue does not happen on Precise (12.04) with kernel version 3.2.0-23.36
5. This issue is caused by the upstream commit below:
f47166d2 drm/i915: Sanitize BIOS debugging bits from PIPECONF
The rationale and original bug description for the above commit can be
found at https:/
6. This issue would be gone if the above commit is reverted on Oneiric kernel
version 3.0.0-19.33 and later ones
7. There is one other commit below which fixed an issue of the above commit
in later kernel version, BUT this commit was verified to have nothing to
do with the issue here:
a9dcf84b drm/i915: don't clobber the pipe param in sanitize_
8. This issue was reported to be related to BIOS version as well (see comment #3)
9. There is a WARN_ON() oops on Oneiric with both kernel versions, but this is
supposedly an unrelated seperate issue, as it happens in both cases, but
presumably fixed in Precise.
10. By comparing the dump contents between two kernels running on Oneiric, the
significant difference is the PIPEACONF register
11. By comparing the dump contents between oneiric and precise, there are many
more registers with different values
Summary
-------
We are able to identify the guilty commit, and are able to provide a workaround
by reverting the commit or by doing PIPECONF register change for non-relevant
machines. However, we are not able to form a correct theory to explain exactly
the above observations and to shape a correct patch to fix the root cause.
| Brad Figg (brad-figg) wrote Missing required logs. | #1 |
| Changed in linux (Ubuntu): | |
| status: | New → Incomplete |
| description: | updated |
| tags: | added: blocks-hwcert-enablement |
| Changed in linux (Ubuntu): | |
| importance: | Undecided → Medium |
| status: | Incomplete → Triaged |
| tags: | added: oneiric |
| James M. Leddy (jm-leddy) wrote | #2 |
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#6 |
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#7 |
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#8 |
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#9 |
| Changed in oem-priority: | |
| importance: | Undecided → Critical |
|
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#10 |
| Changed in linux (Ubuntu): | |
| importance: | Medium → Critical |
| assignee: | nobody → Timo Aaltonen (tjaalton) |
|
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#11 |
| Timo Aaltonen (tjaalton) wrote | #4 |
| Changed in linux (Ubuntu Oneiric): | |
| importance: | Undecided → Critical |
| status: | New → In Progress |
| assignee: | nobody → Timo Aaltonen (tjaalton) |
| Timo Aaltonen (tjaalton) wrote | #5 |
| Changed in linux (Ubuntu): | |
| assignee: | Timo Aaltonen (tjaalton) → nobody |
| status: | Triaged → Fix Released |
| description: | updated |
| Changed in linux (Ubuntu Oneiric): | |
| status: | In Progress → Fix Committed |
| Changed in oem-priority: | |
| status: | New → Invalid |
| Changed in linux: | |
| importance: | Unknown → Medium |
| status: | Unknown → Fix Released |
| Changed in linux (Ubuntu Oneiric): | |
| status: | Fix Committed → Fix Released |
| status: | Fix Released → Fix Committed |
| Herton R. Krzesinski (herton) wrote | #12 |
| tags: | added: verification-done-oneiric |
| Adam Conrad (adconrad) wrote Update Released | #13 |
| Launchpad Janitor (janitor) wrote | #14 |
| Changed in linux (Ubuntu Oneiric): | |
| status: | Fix Committed → Fix Released |
This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:
apport-collect 1041315
and then change the status of the bug to 'Confirmed'.
If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.
This change has been made by an automated script, maintained by the Ubuntu Kernel Team.