xpds14: removing the xen linux upstream delta of various linux distros - luis r. rodriguez, suse
DESCRIPTION
Xen is being used in production by many folks, but are they really using the upstream code? If not what are they using? At least SUSE's supported delta for the Linux kernel consists of 116 patches totaling 353,770 lines of code. Debian has 43 patches for a delta of about 1693 lines of code. What is this delta and how do we shrink it? I will give an overview of the supported Linux kernel delta for Xen at SUSE and Debian with upstream but also layout a proposed roadmap of addressing the delta in collaboration with different teams in the Xen community.TRANSCRIPT
Delta with Xenon the Linux kernel
What’s up with all that delta?@mcgrof
[email protected] R. Rodriguez
http://www.do-not-panic.com
Slides: CC BY-SA Luis R. Rodriguez | Image: CC BY-SA Torkild Retvedt
How big is it?
Citrix: reset two years ago, mostly backportsDebian: 4 microcode patches
SUSE: the largest deltaSLE10: 133 patchesSLE11: 185 patchesSLE12: 110 patches
359,913 lines of codegit://gitorious.org/opensuse/kernel-source.git
patches.xen/Image: CC BY-NC-SA ecololo
Addressing the delta
The xen wiki delta for Linux upstream tracker Luis Rodriguez: IPv6 autoconf, netback
Juergen Gross: pvSCSI, PAT, 500GiB RAMDaniel Kiper: EFI
Konrad Wilk: user mode pvlockBoris Ostrovsky: oprofile support
● Attitude adjustment: work upstream first (™) Is it possible? Future development always upstream
● Backport automatically
Image: CC BY-SA Teza Harinaivo Ramiandrisoa
Needs verificationpci-guestdevmem-hotplughypercall preemption - patch posted, did it go in?multipage ring
Image: CC BY-NC Sergiu Bacioiu
Needs work● pvusb● Expose ballooning limits● Retaining tasklet in netback● Add BLKIF_OP_PACKET, CDROM
command forwarding● CDROM removable media attribute● CDROM avoid takeover in HVM● DCDBAS address translation● Netback multicall for notifications● Interrupt trigger mode and polarity● Logarithmic scale for ballooning
● netfront support skb coalescing● microcode update● MTRR support● Remove VM_IO vestiges● Device hotplug (MODULE_ALIAS)● Suspend event channel support for
faster checkpointing in Remus FT● Expected to be dead code (under
xen) cannot easily be verified to be dead
● Support for old hypervisor (pvops kernel on xen pre-4.0.1 hypervisor)
● blktap driver (what about blktap3?)
Image: CC-BY m4tik