vesafb: mtrr module parameter is uint, not bool
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Fix Released
|
Low
|
Andy Whitcroft | ||
Lucid |
Fix Released
|
Low
|
Andy Whitcroft | ||
Maverick |
Fix Released
|
Low
|
Andy Whitcroft | ||
Natty |
Fix Released
|
Low
|
Andy Whitcroft | ||
Oneiric |
Fix Released
|
Low
|
Andy Whitcroft |
Bug Description
SRU Justification:
Impact: users are unable to specify all possible memory combining modes for vesafb, leading to poor performance
Fix: minor change allowing a greater range of values for the mtrr parameter, from the maintainer of the driver, specific to ubuntu sauce patches
Testcase: use of the module parameter vesafb.mtrr=3 etc works and shows up in /proc/mtrr with the correct permissions
===
The UBUNTU SAUCE patches that add module support to vesafb make the "mtrr" module parameter "bool". This only allows the values 0 and 1, thus no MTRR entries or "uncachable" MTRR entries. To enable write-combining (or write-back) MTRR entries, the "mtrr" module parameter should be "uint" (or "int").
I'll attach two patches, the first makes the described modification, the second one additionally makes write-combining MTRR entries the default. (Just as it already is for e.g. uvesafb.)
Kind regards,
Thomas
Changed in linux (Ubuntu): | |
status: | New → Triaged |
importance: | Undecided → Low |
assignee: | nobody → Andy Whitcroft (apw) |
description: | updated |
tags: |
added: verification-done-natty removed: verification-needed-natty |
Pulled these two patches down and pushed them to kernel-team@ for review. Proposed the first for Lucid and later, and both for Oneiric.