The test kernel in comment #13 was built on top of Ubuntu-3.13.0-76.120. It had the 7 commits listed in comment #18 applied. It did not have the performance regression per comment #14.
The test kernel in comment #19 was built on top of Ubuntu-3.13.0-78.122 I had the 7 commits listed in comment #19 reverted, but it also had the 3.13.11-ckt34 stable updates applied. It still had the regression per comment #28.
This may indicated the regression came in via one of the upstream stable updates.
I'd like to perform a kernel bisect between Ubuntu-3.13.0-76.120 and Ubuntu-3.13.0-78.122. However, we first need to make sure Ubuntu-3.13.0-76.120 does not have the performance regression and Ubuntu-3.13.0-78.122 does have the regression.
Can you test these two kernels for confirmation. Once we have the results, we can start the bisect or decide on the next step:
Note, you need to install both the linux-image and linux-image-extra .deb packages.
In parallel, I will still build you a test kernel with the original 7 commits and commit 757647e applied. I'm in the process of identifying all the prereqs and backporting.
The test kernel in comment #13 was built on top of Ubuntu- 3.13.0- 76.120. It had the 7 commits listed in comment #18 applied. It did not have the performance regression per comment #14.
The test kernel in comment #19 was built on top of Ubuntu- 3.13.0- 78.122 I had the 7 commits listed in comment #19 reverted, but it also had the 3.13.11-ckt34 stable updates applied. It still had the regression per comment #28.
This may indicated the regression came in via one of the upstream stable updates.
I'd like to perform a kernel bisect between Ubuntu- 3.13.0- 76.120 and Ubuntu- 3.13.0- 78.122. However, we first need to make sure Ubuntu- 3.13.0- 76.120 does not have the performance regression and Ubuntu- 3.13.0- 78.122 does have the regression.
Can you test these two kernels for confirmation. Once we have the results, we can start the bisect or decide on the next step:
Ubuntu- 3.13.0- 76.120: https:/ /launchpad. net/~canonical- kernel- security- team/+archive/ ubuntu/ ppa/+build/ 8865557
Ubuntu- 3.13.0- 78.122: https:/ /launchpad. net/~canonical- kernel- team/+archive/ ubuntu/ ppa/+build/ 8926054
Note, you need to install both the linux-image and linux-image-extra .deb packages.
In parallel, I will still build you a test kernel with the original 7 commits and commit 757647e applied. I'm in the process of identifying all the prereqs and backporting.