LKML Summary Podcast

Audio: http://media.libsyn.com/media/jcm/linux_kernel_podcast_20091118.mp3

For Wednesday, November 18th, 2009, I’m Jon Masters with a summary of today’s LKML traffic.

In today’s issue: BKL, Jump Labels, and VMWare.

BKL. Jan Blunck posted version 3 of his latest round of BKL removal by pushing use down to the filesystems. His plan is to later remove the BKL from the VFS entirely, once it is entirely contained within individual filesystems. The latest patches push uses within do_new_mount down to the filesystems, removes the BKL entirely from EXt2 and doesn’t cause filesystems that weren’t using it to acquire a dependency in the cause of the cleanup. Separately, Alan Cox posted a first round of RFC patches doing similar in the tty layer.

Jump labels. Jason Baron posted the latest version of his jump labeling patches. These are intended to introduce a low-overhead conditionally enabled jump mechanism that can be used, for example, in implementing tracing of functions through a selectively enable tracepoint jump label. Matheiu Desnoyers noted that Jason could work around the requirement of disabling lockdep through the use of his “notifier atomic call chain notrace” patch.

VMWare. Dan Merillat started a thread entitled “Linux 2.6.31 – very swap-happy with plenty of free RAM”, in which he detailed how his 64-bit x86 system with 4GB of RAM would start swapping “like crazy” within a few seconds of being given access to a swapfile, despite having 1.7GB of disk cache and 750MB of free RAM. He was running several VMWare VMs, occupying a total of 1GB, which wasn’t a good sign – their kernel module could have been a culprit.

Finally today, is anyone at Coverity listening? Several kernel developers were trying to get in touch with Coverity via their info@, and linux@ addresses and were getting 550 errors, implying that those are no longer valid contacts. But David Maxwell followed up confirming that Coverity continue to perform scans of the kernel source against their source code checker (detecting common bugs from source level inspection), adding that some glitch had caused the most recent run to be on September 14th. He is short of time to keep the scan site updated, which it was noted by others had not been updated in “years”. David also provided some feedback concerning how the results of scans are shared with a select group of people, including various maintainers.

In today’s announcements: LTTng version 0.174. Mathieu Desnoyers posted yet another version of LTTng. The 0.714 release fixes a missing del_timer and buggy mips32 clock tracing support. This release was quickly followed by the 0.175 release. The second day in a row with multiple releases.

The latest kernel release was 2.6.32-rc7.

Stephen Rothwell posted a linux-next tree for November 18th. Since Tuesday, the net tree lost a conflict (but gained a build failure for which Stephen applied a patch), and the trivial, omap_dss2, and sysctl trees lost their conflicts. The total sub-tree count remained at 151 trees.

That’s a summary of today’s Linux Kernel Mailing List traffic, for further information visit www.kernel.org. I’m Jon Masters.