Guest Blog

Greetings, and welcome!

-Starting this week’s news, The H Online have , since the 24th of March,  a series of articles titled “What’s new in 2.6.34”. You can find it here: http://www.h-online.com/open/features/Linux-Kernel-2-6-34-tracking-962586.html

-Frederic Weisbecker posted perf fixes for 2.6.34, James Bottomley came up with SCSI fixes for -rc6, Paul E. McKenney had some RCU fixes for 2.6.35; perf fixes came also from Arnaldo Carvalho de Melo.

-Christoph Hellwig posted a XFS status update for April 2010; we will paste his report here in its’ entirety to let you get a clear picture : “In April 2.6.34 still was in the release candidate phase, with a hand full of XFS fixes making it into mainline.  Development for the 2.6.35 merge window went ahead full steam at the same time.

While a fair amount of patches hit the development tree these were largely cleanups, with the real development activity happening on the mailing list.  There was another round of patches and following discussion on the scalable busy extent tracking and delayed logging features mentioned last month.  They are expected to be merged in May and queue up for the Linux 2.6.35 window.  Last but not least April saw a large number of XFS fixes backported to the 2.6.32 and 2.6.33 -stable series.

In user land xfsprogs has seen few but important updates, preparing for a new release next month.  The xfs_repair tool saw a fix to correctly enable the lazy superblock counters on an existing filesystem, and xfs_fsr saw updates to better deal with dynamic attribute forks.  Last but not a least a port to Debian GNU/kFreeBSD9 got merged. The xfstests test suite saw two new test cases and various smaller fixes.”

-As usual, Rafael J. Wisocki announced the series of reported regressions from 2.6.33 (referring to 2.6.34-rc6-git6).

-No doubt, the most important news of this week is Linus’ announcement of 2.6.34-rc7 : “I think this is the last -rc – things have been pretty quiet on the patch front, although there’s been some rather spirited discussions.Random fixes all around, some of them RCU related (people fixing various RCU sanity check warnings), but most of them just random driver fixes. And there’s some MIPS, microblaze and ARM updates, and ocfs2 and ceph fixes. The shortlog is about as informative as anything else – nothing there  stands out in my mind, it’s just a lot of small random stuff.”

-OpenSUSE’s Jiri Kosina posted HID fixes, while H. Peter Anvin posted a RFC regarding virtualization – the hypervisor layer pertaining Hyper-V and VMware code cleanups.

-Robert Richter came up with oprofile hotplug fixes for x86, sound fixes came from Takashi Iwai, perf from Arnaldo Carvalho de Melo, wireless by John W. Linville, drm fixes by Dave Airlie and networking fixes by David Miller.

-The H Online features another interesting kernel log; you can read it, along with its interesting links, here http://www.h-online.com/open/features/Kernel-Log-New-stable-kernels-and-drivers-995820.html .

-Paul McKenney posted fixes for the RCU tree (for 2.6.35, rebased for -rc7), hwmon fixes appeared courtesy of Jean Delvare, some new perf fixes by Ingo Molnar and later by Arnaldo Carvalho de Melo, tracing by Steven Rostedt, AMD iommu by Joerg Roedel, patches for the s390 series for -rc7 by Martin Schwidefsky and some perf_event fixes for powerpc by Benjamin Herrenschmidt.

-Greg Kroah-Hartman posted the “start of the stable review cycle for the 2.6.32.13 release”, stating that “There are 98 patches in this series, all will be posted as a response to this one. If anyone has any issues with these being applied, please let us know.  If anyone is a maintainer of the proper subsystem, and wants to add a Signed-off-by: line to the patch, please respond with it.”

-The same Greg started the review process for 2.6.33.4, with the same message to anyone involved/interested.

-Pierre Tardy informed the community about PyTimechart by posting a RFC :  “PyTimechart is another implementation of two very useful tools available for the linux community: perf-timechart ( http://blog.fenrus.org/?p=5 ) and bootchart (http://www.bootchart.org/ ) The two tools share a common idea of making their output to SVG files. While it is a very good idea for small traces, the generated SVG can be very heavy, and turns out to be good stress tests for inkscape developers…
PyTimechart is a tool that parses ftrace text traces, and display them with the help of a very powerful dynamic plot framework, Chaco (http://code.enthought.com/chaco/ ) The GUI makes the best it can to ease the browsing of huge traces.”
All in all, the respondents to this mail seemed to welcome the application as being useful.

-In the latest fixes/patches/pull requests section, we have Paul E McKenny with an RCU lockdep splat fix, Sage Weil with ceph fixes for 2.6.34-final, Frederic Weisbecker has perf/nmi fixes (uniform lockup detector), Takashi Iwai with some sound fixes; Samuel Ortiz has some MFD fixes and Steve French came up with some minor cifs fixes.

-Greg Kroah-Hartman of OpenSUSE made the announcement of the release of kernels 2.6.32.13 and 2.6.33.4 .

-Marcello Tosatti announced a series of fixes for the kvm targetting 2.6.34-rc7, Greg Kroah-Hartman posted patches for the -git kernel regarding TTY, Steven Rostedt had some tracing updates, perf fixes by Arnaldo Carvalho de Melo were posted too, and Dmitry Korokhov has fixes for the input tree.

-Mathieu Desnoyers announced the release of LTTng 0.213, with various bugfixes and improvements.

-As usual, at least lately, Michal Simek has some patches/fixes for arch/microblaze, this time for -rc8.

-Michael S. Tsirkin posted “a last minute vhost-net fix” which fixes barrier pairing.

Well, that’s it for this week’s OpenSUSE-flavoured kernel news!
I’m off, enjoy the weekend!

Hello, and welcome. Here goes :

-This first one is hot after the closing of the last weeks’ edition, courtesy of LWN.net (I had not access to vger.kernel.org because of their downtime) : Linus Torvalds announced 2.6.34-rc6  (http://www.kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.34-rc6) and here is the link from LWN : http://lwn.net/Articles/385535/rss
-On the fixes side, we begin with Trond Myklebust’s NFS client bugfixes , and continue with a small fix from Jens Axboe regarding the block tree; in related news, other fixes are : xfs (Alex Elder), kgdb for  -rc5 (Alex Elder), perf (Arnaldo Carvalho de Melo), spi/gpio (Grant Likely), USB for -rc4-git (Greg Kroah-Hartman), who also sent fixes for the tty and staging trees.
-Stefan Bader announced linux-2.6.32.y-drm33.z with the following comment : “As many of us now have a distribution which is based on a 2.6.32 kernel but are forced to update DRM to the version in 2.6.33 to obtain good graphics experience. In support of this I went ahead and created a tree on kernel.org[1] which brings together the two and which I will maintain following the upstream stable trees from Greg. This hopefully will not only be beneficial to us but also to all that are in the need of running this combination of code.”
-Tim Gardner of Canonical proposed some of the updates to the r8169 driver should be merged into stable; Francois Romieu agreed, so we’ll see these fixes in .32 and .33 stable versions.
-Darrick j. Wong posted a RFC in regard of the ext4 tree with the following intro-duction : “Hmm.  A while ago I was complaining that an evil program that calls fsync() in a loop will send a continuous stream of write barriers to the hard disk.  Ted theorized that it might be possible to set a flag in ext4_writepage and clear it in ext4_sync_file; if we happen to enter ext4_sync_file and the flag isn’t set (meaning that nothing has been dirtied since the last fsync()) then we could skip issuing the barrier. Here’s an experimental patch to do something sort of like that.  From a quick run with blktrace, it seems to skip the redundant barriers and improves the ffsb mail server scores.  However, I haven’t done extensive power failure testing to see how much data it can destroy.  For that matter I’m not even 100% sure it’s correct at what it aims to do.”
-John W. Linville asked Dave Miller to pull some of his fixes applied to the wireless-2.6 tree (30.04.2010).
-Linux Weekly’s editor-in-chief, Jonathan Corbet, RFC’d some fixes for the viafb tree (OLPC).
-Paul E. McKenney announced fixes for the RCU tree in .34 and changes for .35,  Frederic Weisbecker sent Ingo Molnar and the list some new fixes for perf,  lockdep and hw-breakpoints, Michael S. Tsirkin came up with vhost-net improvements,  just like Sage Weil, who posted ceph fixes for -rc7; other fixes include lockdep, RCU, i2c, tracing and core.
-Joel Becker wrote fixes for the ocfs tree, while H. Peter Anvin posted x86 fixes for -rc7, including David Howell’s rwsem patch.
-Another series of small fixes for the drm and gpu trees by Dave Airlie were  posted, as well as other fixes for the following trees/components :  input by Dmitry Torokhov, sound by Takashi Iwai, networking by David Miller, wq (workqueue) by Tejun Heo and perf by Arnaldo Carvalho de Melo.
-Pankaj Thakkar of Vmware posted a RFC in regard of NPA for vmxnet3, with the  following words : “Device passthrough technology allows a guest to bypass the hypervisor and drive the underlying physical device. VMware has been exploring various ways to deliver this technology to users in a manner which is easy to adopt. In this process we have prepared an architecture along with Intel – NPA (Network Plugin Architecture). NPA allows the guest to use the virtualized NIC vmxnet3 to passthrough to a number of physical NICs which support it. The document below provides an overview of NPA. We intend to upgrade the upstreamed vmxnet3 driver to implement NPA so that Linux users can exploit the benefits provided by passthrough devices in a seamless manner while retaining the benefits of virtualization. The document
below tries to answer most of the questions which we anticipated. Please let us know your comments and queries.”
-On opensuse-kernel@ Larry Finger patched the script allowing the downloading of firmware for b43 (Broadcom).
-Another series of fixes were posted as follows : SLAB for -rc7 by Pekka J. Enberg,  libata and zerolen (misc) by Jeff Garzik, RCU for 2.6.34 by Paul E. McKenney, sh by Paul MUndt, arch/microblaze by Michal Simek, oprofile by Robert Richter, RCU, this time by Ingo Molnar, vrl/dvb by Mauro Carvalho Chehab, nfs client  fixes by Trond Myklebust, sched/core by Tejun Heo, drm by Dave Airlie,  ACPI for -rc6 by Len Brown, perf and tracing by Steven Rostedt, block for 2.6.34 by Jens Axboe, PCMCIA by Dominic Brodowski and md for 2.6.34 by Neil Brown.
-Soeren Sandmann announced the release of Sysprof 1.1.6 with the following  words : “Sysprof 1.1.6 is now available. This is a development release leading up to a stable 1.2.0 release. Sysprof is a sampling system-wide CPU profiler for Linux. This version is based on the perf counter interface in 2.6.31 kernels and will not work with earlier kernels.”
-Mikulas Patocka asked for testers in the matter of performance degradation in the Maxtor Atlas 15K2 SCSI disks, due to buggy firmware, posting a script that limits the request size to 256k, since the degradation appears when requests exceed this 256k boundary
That’s all, folks! If you’re in Europe, have a rainless weekend, and may all
of you have a fantastic weekend!