LKML Summary Podcast

Audio: http://media.libsyn.com/media/jcm/linux_kernel_podcast_20090827.mp3

For Thursday, August 27th, 2009, I’m Jon Masters with a summary of today’s LKML traffic.

In today’s issue: RAID, Stable review patches, and syncing.

RAID. Pavel Machek (in a typically provocative style) replied to an email thread that had been discussing how to document potential unreliabilities in using ext2 and ext3 on certain kinds of backing block device, with the subject “raid is dangerous but that’s secret”, and a direct comparison between the kernel community and some hyperthetical automotive manufacturer being aware of their ABS having flaws but deciding not to tell anyone about it anyway. He adds that he expects “slightly higher moral standards”, though one wonders whether documetation alone can ever truly guarantee that to be the case.

Stable review patches. Luis R. Rodriguez wondered aloud whether more should be done to encourage and enable users to test stable patches prior to them hitting the stable tree. Althoug Greg and many others do a great job with the stable updates, Luis is interested to find out whether there should be more exposure to online resources, such as the stable-review vger mailing list.

SYNC. Christoph Hellwig, Jamie Lokier, and Ulrich Drepper had a debate surrounding the O_SYNC and O_DSYNC flags one can pass to file operations. Christoph wondered aloud whether it might be possible for Linux to change the meaning of O_SYNC and start using O_DSYNC within the C library on newer kernels. Ulrich followed up saying that it is not possible to change the meaning of existing flags, which the various Open Group standards apparently don’t mandate should be handled by the underlying system call, which is free to not handle them if it would like to do so. Uli suggested adding a new sys_newopen that would fail when given unknown flags as parameters.

In today’s miscellaneous items: a fix to the perf tools to handle importing task comms (running task names) for ftrace event tracing from Frederic Weisbecker, a SCSI driver for VMWare’s virtual HBA from Alok Kataria, a fix to the RTC code for certain devices, explicitly marking them as “wakeup capable” from Anton Vorontsov, some further syscall tracing patches from Frederic Weisbecker, some kmemleak patches for 2.6.32 from Catalin Marinas, version 5 of the vhost kernelspace virtio server optimization from Michael S. Tsirkin, some early CPU load-balancing rework patches from Peter Zijlstra, a patch removing bd_mount_sem from Fernando Luis Vazquez Cao (which also causes a small user-visible semantic change, returning -EBUSY if a filesystem is frozen rather than blocking the mount task in an uninterruptible state for an indetermininate time interval), some plan 9 fixes from Eric Van Hensbergen, a fix to the AFS implementation that corrects handling of symbolic links that prevously resulted in crashes from David Howells, some fixes to inotify from Eric Paris (including a terminating null on filename fix), version 3 of the cpuidle patches for POWER from Arun R Bharadwaj, a few m68k fixes, a fix to task group weight ratio calculations such that they don’t result in a divide-by-zero from Peter Zijlstra, a slow-work conversion patch for libata from Jens Axboe, a patch to performance counters removing any hint of ABI preservation guarantees in trace-events from Peter Zijlstra, and some tracing fixes for s390 systems from Hendrik Brueckner.

In today’s announcements: Linux version 2.6.31-rc8. Linus Torvalds announced the release of Linux 2.6.31-rc8 on Thursday evening at 6:24pm PDT (Best Coast Time). In his announcement, Linus says that this should really be the final RC since things have “really been quieting down”. He’s right that most of the recent stuff hitting the tree has been relatively trivial, and so this should result in a 2.6.31 final release hitting the intertubes as forecast around the US Labor Day weekend holiday (when many of us will be away anyway).

The latest kernel release is 2.6.31-rc8, released this evening.

Andrew Morton posted an mm-of-the-moment for 2009-08-27-16-51 (which superceeded the one he also posted at 2009-08-27-00-57).

Gregory Haskins noticed that the ftrace function-graph tracer had suddenly stopped working for him in moving from rc6 to rc7, although others could not reproduce this behavior (including Ingo Molnar, who said as much).

Stephen Rothwell posted a linux-next tree for August 27th. Since Wednesday, the uwb tree lost its build failure and the tip tree lost a conflict. The total subtree count remains steady at 141 in today’s linux-next compose.

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