Kernel Log: Linux 2.6.25 with Smack security framework, LCA08 online

In mere under two weeks since Linux 2.6.24 was released, 7931 patches have been incorporated into the Linux kernel development branch maintained by Linus Torvalds, from which Linux 2.6.25 should eventually emerge in about two months time. The Simplified Mandatory Access Control Kernel (Smack) security framework has been added to the new features described in the last Kernel Log. Like SELinux, it offers mandatory access control (MAC), but deliberately foregoes many of the other protective functions offered by SELinux. This is intended to make Smack much easier to handle than SELinux, which has the reputation of being difficult to use.

The development team has definitively removed a number of OSS sound drivers, such as i810_audio and via82cxxx_audio, as the kernel now includes Alsa sound drivers for the same hardware. The MAC80211 WLAN Stack is no longer marked as experimental. Various patches under the banner of maps4 and "Proportional Set Size" (PSS) should in future allow more precise analysis of memory allocated to userspace programs. Torvalds has also incorporated various Virtio patches, including the balloon driver, which allows the amount of memory on the guest system to be adjusted at run time.

A few days after the event's conclusion, the organisers of linux.conf.au (LCA), which was attended by many Linux programmers, have made audio and video edits of almost all of the talks and many of the presentations available online. You can now watch the opening keynote speech on "Reconceptualizing Security", given by security expert Bruce Schneier, at your leisure without visiting the Southern hemisphere.

The talk entitled "Make hardware vendors love open source", given by Intel's Dirk Hohndel, offered many reasons why some hardware vendors fail to get to grips with the open source concept. Users should also inform hardware vendors when they use Linux instead of Windows on their laptops. Long-established kernel and X developer Dave Airlie also took aim at hardware vendors in his talk "Bringing kittens back to life – continuing story of open source graphics drivers", out of which Nvidia does not come well - the Californian company provides open source programmers with negligible information on driver development. ATI was subjected to similar criticism in a previous version of Airlie's talk, but has since smartened up its act by distributing documentation and even sponsoring development of an open source driver.

Several developments likely to find their way into forthcoming Linux distributions were also described or demonstrated in talks at LCA08. Jonathan Corbet, founder and executive editor of LWN.net delivered an updated version of his familiar talk on kernel development and forthcoming new features in Linux. Veteran X hacker Keith Packard reported on the latest developments with the X server in "Roadmap to recovery: Pain and Redemption in X driver development".

Kernel version 2.6.22.17, discussed in the last Kernel Log has now been released. This should be the last version in the 2.6.22 stable series and fixes the security problems related to core dumps (see: CVE-2007-6206) and mmap. The kernel development team recommends that 2.6.22 users upgrade to the latest version. Kernel version 2.6.23.15 is currently in preparation. With 73 patches, it represents a relatively major revision and should be released at the weekend.

Kernel Log staccato: Torvalds has now clarified why he has chosen not to include the KGDB kernel debugger in version 2.6.25. The GCC development team is releasing version 4.2.3 of the GNU compiler collection. The Madwifi Project has joined "Software in the Public Interest" (SPI) and is now able to accept donations from users through SPI. Chris Mason has released version 0.12 of the experimental Btrfs file system, which is much faster than the previous version in certain Tiobench tests. The Linux Foundation has released the second part of a very wide-ranging interview with Linus Torvalds.

(mba)