[SRU] new arm64 optimized copy_to_user and copy_from_user assembly code
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Fix Released
|
Medium
|
Unassigned | ||
Trusty |
Fix Released
|
Medium
|
Unassigned | ||
Utopic |
Fix Released
|
Medium
|
Unassigned |
Bug Description
[Impact]
The copy_{to,from}_user implementations in the Ubuntu kernel are suboptimal. Optimized implementations have been submitted upstream and have shown a significant improvement in network performance.
[Test Case]
Generate traffic from one node to another using iperf.
[Regression Risk]
These functions are obviously used heavily throughout the kernel, so a defect here could have significant impact. This risk is mitigated by using an implementation heavily based on the linaro string libraries (which are used in other places already, e.g. glibc), and through active testing of this patch on real hardware using a trusty-kernel base. The new patch will also undergo regression testing to ensure the memory corruption issue of the previous patch does not exist.
tags: | added: hs-arm64 |
Changed in linux (Ubuntu): | |
importance: | Undecided → Medium |
tags: | added: kernel-da-key |
tags: | added: patch |
Changed in linux (Ubuntu): | |
status: | Confirmed → Fix Committed |
Changed in linux (Ubuntu Utopic): | |
status: | New → Fix Committed |
Changed in linux (Ubuntu Trusty): | |
status: | New → Fix Committed |
importance: | Undecided → Medium |
Changed in linux (Ubuntu Utopic): | |
importance: | Undecided → Medium |
tags: |
added: verification-done-utopic removed: verification-needed-utopic |
tags: |
added: verification-done-trusty removed: verification-needed-trusty |
This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:
apport-collect 1400349
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.