[Xen-devel] Xen 4.5 development update (September update). Feature freeze slip by two weeks.

[konrad.wilk@xxxxxxxxxx]

The feature freeze has moved by two weeks. That means it is scheduled
to be on September 24th.

If you think you will need a feature freeze exception, read below.

In terms of Linux I am keeping the 'fair' ones as by the Xen 4.6 release
it could be v3.19, which means there is still an upcoming merge window
for those.

The "prognosis" is now the likelihood of completion in the 4.5 timeframe.
A bunch of items had moved to the completed phase which is fantastic.

none - nothing yet
fair - still working on it, patches are prototypes or RFC
ok   - patches posted, acting on review
good - some last minute pieces
done - all done, might have bugs

For items involving code hosted on the Xen.org site (including qemu-xen),
that means a likelihood of having the feature code-complete and mostly
working by the feature freeze.  (It's OK if there are still bugs to be
worked out.)  For items in Linux, it would mean having items on track
to make it into the kernel released just after the scheduled 4.5 time frame.

In terms of libvirt it has monthly releases. As such not going to track
every release - but closer to when RCs are out.

= Timeline =

We are planning on a 9-month release cycle.  Based on that, below are
our estimated dates:


* Feature Freeze: 24th September 2014
* First RC: 15th October
* Release: 10th December 2014

The RCs and release will of course depend on stability and bugs, and
will therefore be fairly unpredictable.  The feature freeze may be
slipped for especially important features which are near completion.

If you think your patchset MUST go in Xen 4.5 I will post the procedure
for requesting an exception to get them in past the feature freeze next
week.

= Prognosis =

The states are: none -> fair -> ok -> good -> done

none - nothing yet
fair - still working on it, patches are prototypes or RFC
ok   - patches posted, acting on review
good - some last minute pieces
done - all done, might have bugs

= Feature freeze exception =

When we get to September 24th, the code "freezing point" will commence;
which means that starting on that day non-bug fixes need a freeze exception
to be included.

Remember our goal for the release:
  1. A bug-free release
  2. An awesome release
  3. An on-time release

Accepting a new feature may make Xen more awesome; but it also
introduces a risk that it will introduce more bugs.  That bug may be
found before the release (threatening #3), or it may not be found
until after the release (threatening #1).  Each freeze exception
request will attempt to balance the benefits (how awesome the
exception is) vs the risks (will it cause the release to slip, or
worse, cause a bug which goes un-noticed into the final release).

The idea is that today we will be pretty permissive, but that we will
become progressively more conservative until the first RC, which is
scheduled for 3 weeks' time (October 15).  After that, we will only
accept bug fixes.

Bug fixes can be checked in without a freeze exception throughout the
code freeze, unless the maintainer thinks they are particularly high
risk.  In later RC's, we may even begin rejecting bug fixes if the
broken functionality is small and the risk to other functionality is
high.

Features which are currently marked "experimental" or do not at the
moment work at all cannot be broken really; so changes to code only
used by those features should be able to get a freeze exception
easily.

Features which change or add new interfaces which will need to be
supported in a backwards-compatible way (for instance, vNUMA) will
need freeze exceptions to make sure that the interface itself has
enough time to be considered stable.

These are guidelines and principles to give you an idea where we're
coming from; if you think there's a good reason why making an
exception for you will help us achieve goals 1-3 above better than not
doing so, feel free to make your case.

= Open =

== ARM ==

*  ARM Xen UEFI booting on ARM (fair/ok)
   v4
  -  Roy Franz

*  ARM GICv3 support (ok)
   v10 posted
  -  Vijay Kilari

*  ARM - VGIC emulation (ok)
   Reposted as gic and vgic fixes and improvements
   v12
  -  Stefano Stabellini

*  ARM - Add Odroid-XU (Exynos5410) support (ok)
   v6
  -  Suriyan Ramasami

*  ARM implement mem_access (ok)
   v5
   https://github.com/tklengyel/xen/tree/arm_memaccess5
  -  Tamas K Lengyel

== x86 ==

*  xc_reserved_device_memory_map in hvmloader to avoid conflicting MMIO/RAM 
(good)
   v6
  -  Tiejun Chen

*  New Migration (v2). (good)
   v6 posted, going on the 'good' side!
  -  Andrew Cooper & David Vrabel

*  PVH - AMD hardware support. (fair)
   Posted.
  -  Mukesh Rathor

*  VMware backdoor (hypercall) (ok)
   v2 posted.
  -  Don Slutz

*  VPMU - 'perf' support in Xen (good)
   v10 posted
   Need perf aware person to review for final ack.
  -  Boris Ostrovsky

*  Cache QoS Monitoring - hypercalls (ok)
   Just hypercalls - no toolstack changes.
   v15
   Hit a snag with rdmsr/IPI/wrmsr/IPI, possible redesign
  -  Chao Peng, Dongxiao Xu, and Shantong Kang

*  XenRT (Preemptive Global Earliest Deadline First) (good)
   v2
  -  Meng Xu

*  Introspection of HVM guests (ok)
   v6
  -  Razvan Cojocaru

*  Xen Boot Information (xbi) (fair)
   Dependency for GRUB2 + EFI work
   See http://lists.xen.org/archives/html/xen-devel/2013-05/msg02281.html
  -  Daniel Kiper

== lib{xc,xl} and toolstack ==

*  vNUMA in Xen toolstack (ok)
   v11 posted
   Hypervisor part in
   git://gitorious.org/vnuma/xen_vnuma.git:v11
  -  Elena Ufimtseva

*  Remus in Xen (libxl) (good)
   v19
   url:  https://github.com/macrosheep/xen/tree/remus-v19
  -  Gui Jianfeng
  -  Yang Hongyang
  -  Dong, Eddie

== Linux ==

*  Linux block multiqueue (fair)
  -  Arianna Avanzini

*  Netback grant table manipulations (ok)
  -  Zoltan Kiss

*  VPMU - 'perf' support in Linux (ok)
   Depends on Xen patches
  -  Boris Ostrovsky

*  vNUMA in Linux (ok)
   v6 posted
   git://gitorious.org/vnuma/linux_vnuma.git
  -  Elena Ufimtseva

*  vsyscall in Linux (fair)
  -  Konrad Rzeszutek Wilk

*  COLO Agent in Linux (fair)
  -  Gui Jianfeng
  -  Yang Hongyang
  -  Dong, Eddie

*  vAPIC in PVHVM guests (Linux side) (none)
  -  Boris Ostrovsky

*  ARM - Device assigment usage in Linux code (arch/arm) (none)
  -  Julien Grall

*  Fix PAT in Linux kernel (aka Full support for PAT) (ok)
  -  Juergen Gross

*  Linux ARM - Device assigment (fair)
  -  Julien Grall

== FreeBSD ==

*  PVH FreeBSD dom0 (ok)
   FreeBSD 11 goal. Toolstack side done in Xen 4.5
  -  Roger Pau Monné

== Other OSes (MiniOS, QNX) ==

*  PV drivers for automotive kernels (fair)
  -  Artem Mygaiev

*  mini-os: xenbus changes for rump kernels (ok)
   git://xenbits.xen.org/people/iwj/rumpuser-xen.git
   branch: base.dev-xen-xenbus.v1..dev-xen-xenbus.v1
   v2 posted
  -  Ian Jackson

== GRUB2 ==

*  GRUB2 multiboot2 (fair)
  -  Daniel Kiper

== OSSTEST ==

*  OSSTest: libvirt (good)
  -  Ian Campbell

== Deferred to QEMU v2.next ==

*  Using qemu-upstream in a stubdomain (fair)
   Will use rump kernels.
  -  Ian Jackson

*  AMD Radeon PCI GPU passthrough (none)
   Focusing on Xen 4.2 and qemu-traditional
  -  Kelly Zytaruk

*  Intel IGD PCI GPU passthrough (ok)
   v5 posted
  -  Chen, Tiejun

*  Xen PV block driver in OVMF (UEFI in guest) (ok)
   v1
  -  Anthony PERARD

== Deferred to Xen hypervisor 4.6 ==

*  extending mem_access support to PV domain (fair)
   RFC v2
  -  Aravindh Puthiyaparambil (aravindp)

*  Repurpose SEDF Scheduler for Real-time (fair)
   RFC patch posted (v2)
  -  Joshua Whitehead, Robert VanVossen

*  ARM remote processor iommu module (GPUs + IPUs) (fair)
   v3 posted
  -  Andrii Tseglytskyi

*  dirty vram / IOMMU bug (fair)
   http://bugs.xenproject.org/xen/bug/38
  -  Zhang, Yang Z

*  Xen multiboot2-EFI support (fair)
   Needed for GrUB2
   Depends on Xen Boot info (rework multiboot and other structs)
   See http://lists.xen.org/archives/html/xen-devel/2013-05/msg02281.html
   RFC posted
  -  Daniel Kiper

*  Support controlling the max C-state sub-state (ok)
   v3 posted
  -  Ross Lagerwall

*  IOMMU ABI for guests to map their DMA regions (fair)
  -  Malcolm Crossley

*  Default to credit2 (none)
   cpu pinning, numa affinity and cpu reservation
  -  George Dunlap

*  Convert tasklet to per-cpu tasklets (fair)
   RFC posted
  -  Konrad Rzeszutek Wilk

*  Further tmem cleanups/fixes (16TB etc) (fair)
  -  Bob Liu

*  1TB slow destruction (ok)
  -  Bob Liu

*  ARM VM save/restore/live migration (none)
   Need to rebased against migrationv2 - no code posted.
  -  Junghyun Yoo

*  ARM GICv2m support (none)
  -  Linaro (unknown)

== Deferred to Xen toolstack 4.6 ==

*  pvscsi in libxl (fair)
  -  Juergen Gross and Olaf

*  COarse-grain LOck-stepping Virtual Machines in Xen (fair)
   RFC v3 posted, based on remus-v19
  -  Wen Congyang
  -  Gui Jianfeng
  -  Yang Hongyang
  -  Dong, Eddie

*  extend the xenstore ring with a 'closing' signal (fair)
   RFC patch posted
  -  David Scott

*  libxl migrationv2 patches. (none)
  -  Andrew Cooper & David Vrabel

*  tmem migrationv2 patches. (none)
  -  Bob Liu & Andrew Cooper & David Vrabel

*  Remus using migration-v2 (fair)
   RFC posted - depends on v6 of 'New Migration'
  -  Yang Hongyang

*  snapshot API extension (checkpointing disk) (ok)
   v5
   His email bounces.
  -  Bamvor Jian Zhang

*  Rearrange and cleanup installation destination directories (/var -> 
var/lib/xen) (fair)
  -  Daniel Kiper

*  libxl/xl - xm compatibility mode for mem-max and mem-set; (ok)
  -  Daniel Kiper

*  xl list --long (and some related xl commands) have some bugs (none)
  -  Zhigang Wang

*  Xen HPET interrupt fixes (fair)
   behind migration v2
  -  Andrew Cooper

*  cpuid leveling (none)
   
http://xenbits.xen.org/people/andrewcoop/feature-levelling/feature-levelling-D.pdf
  -  Andrew Cooper

*  live migration knobs, there is no suitable code yet, just ideas (none)
    http://lists.xenproject.org/archives/html/xen-devel/2014-03/msg00785.html
  -  Olaf Hering

*  xl does not handle migrate interruption gracefully (none)
   If you start a localhost migrate, and press "Ctrl-C" in the middle, you get 
two hung domains
  -  Ian Jackson

*  IO-NUMA - hwloc and xl (none)
   Andrew Cooper had an RFC patch for hwloc
   add restrictions  as to which devices cannot safely/functionally be split 
apart.
  -  Boris Ostrovsky

*  HVM guest NUMA (none)
  -  Matt Wilson

*  PVH - Migration of PVH DomUs. (none)
   Depends on migration2 code
  -  Roger Pau Monné

*  PVH - Migration of guests from a PVH dom0  (none)
   Depends on migration2 code
  -  Roger Pau Monné

*  "Short" grant copy (just header) of packets. (none)
  -  Zoltan Kiss

== Up for grabs ==

*  OSSTest - also test Linux PVH guests

*  PoD fixes
   if you boot with memory <= maxmem we have a size estimation bug

*  TLB flushing without locks in Xen

*  xl does not support specifying virtual function for passthrough device
   http://bugs.xenproject.org/xen/bug/22

*  PCI hole resize support hvmloader/qemu-traditional/qemu-upstream with 
PCI/GPU passthrough
   http://bugs.xenproject.org/xen/bug/28

*  libx{c,l} error handling cleanup

*  Adding missing 'xend' features in libxl

*  xl list -l on a dom0-only system

*  xl list -l doesn't contain tty console port

*  xl: passing more defaults in configuration in xl.conf
   There are a number of options for which it might be useful to pass a default 
in xl.conf.  For example, if we could have a default "backend" parameter for 
vifs, then it would be easy to switch back and forth between a backend in a 
driver domain and a backend in dom0.

*  PVH - PVH working with shadow.
   Based on Tim's work

*  PVH - PCI passthrough for DomU.

*  AMD performance regressions

*  Performance due to hypercall preemption. More preemptions - slower. (none)

== Completed ==

*  ARM - MiniOS (done)
   v7 posted
  -  Thomas Leonard

*  ARM XEN_DOMCTL_memory_mapping hypercall for ARM (done)
   v12 posted.
  -  Arianna Avanzini

*  libxl work - JSON to keep track of guest configs (done)
  -  Wei Liu

*  ARM - XENFEAT_grant_map_11 (aka map grants refs at pfn = mfn) (done)
   Provide kernels an grant->MFN lookup
   v4
  -  Stefano Stabellini

*  ARM PSCI v0.2 (done)
   v11 posted
  -  Parth Dixit

*  pvSCSI in Linux (fronted and backend) (done)
   v6
  -  Juergen Gross

*  alternative_asm in Xen (done)
  -  Feng Wu

*  SMAP (done)
  -  Feng Wu

*  Re-write of vHPET (done)
   aka hvm/hpet: Detect comparator values in the past
  -  Don Slutz

*  vAPIC in PVHVM guests (Xen side) (done)
  -  Boris Ostrovsky

*  libvirt and xl discard support, so that libvirt can start using it (done)
  -  Olaf Hering

*  Xen PVH dom0 (done)
  -  Mukesh Rathor

*  Linux PVH dom0 (done)
  -  Mukesh Rathor

*  OSSTest: upstream QEMU (done)
  -  Ian Campbell

*  amd_ucode cleanups, verify patch size(enhancement) (mostly in master except 
one patch)

*  Data breakpoint Extension support (new-feat) (in master)

*  Feature masking MSR support (enhancement) (in master)

*  Support BRCM TruManage chip (Serial over LAN support) (new-feat) (in master)

*  fix vmce_amd* functions, unify mce_amd mcheck initialization (fixes/cleanups)

*  multiple AMD container files appended together in initrd (early initramfs)
  -  Aravind and Suravee

*  NUMA memory scrubbing (done)
  -  Konrad Rzeszutek Wilk

*  ARM  - IOMMU support (done)
  -  Julien Grall

*  ioreq-server, aka secondary emulators (done)
  -  Paul Durrant

*  Netback multiqueue (good)
  -  Wei Liu

*  ARM Interrupt latency reduction (no maintenance interrupts) (good)
  -  Stefano Stabellini

*  Bigger PCI hole in QEMU (done)
   Needs to be rebased
  -  Don Slutz

*  ARM DRA7 support (done)
   v3 posted
   v3 with comments applied
  -  Andrii Tseglytskyi

*  rework VM Generation ID (done)
   v7 posted
  -  David Vrabel

*  Soft affinity for vcpus (was NUMA affinity for vcpus) (good)
   v11 posted
  -  Dario Faggioli

*  Linux pvops of Xen EFI hypercall support (done)
  -  Daniel Kiper

*  ARM: Use super pages in p2m (done)
   v5 posted
  -  Ian Campbell

*  QEMU 2.0 branch for qemu-upstream (done)
   It is v2.0 with 2.1 Xen backports.
  -  Stefano Stabellini

*  systemd support (done)
   v11
  -  Luis R. Rodriguez

*  Soft affinity for vcpus libxl/xl changes (done)
   v13 posted
  -  Dario Faggioli

*  HT enabled, virtualization overhead is high (Xen 4.4) (done)
   kernbench demonstrated it
   Looking and tracing
   http://www.gossamer-threads.com/lists/xen/devel/339409
   False alarm.
  -  Dario Faggioli


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel