[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

looking for advice on kvm update


KVM is currently at version 71+dfsg-1 in testing and unstable. Upstream
has released version 72 on 2008-07-28 with many fixes (but also some
other changes).

The current package has broken migration and the alsa sound output has
been disabled (upstream changed the configure options without notice).
I've got these fixed with minimal changes in the git repo:

>From the upstream changelog:

 * fix ia64 build breakage (Xiantao Zhang)
 * merge qemu-svn
  * fixes suspend/resume of multiple nics
 * add 'push mem' to patched tpr instructions
 * use host kernel anon_inodes support if available
 * robustify signalfd() emulation
 * avoid losing the iothread on random signals
 * fix test for iothread (Jan Kiszka)
 * fix compile warning (Carlo Marcelo Arenas Belon)
 * fix duplicate #include (Carlo Marcelo Arenas Belon)
 * avoid tpr patching when the stack is not valid (Marcelo Tosatti)
  * fixes some variant of Windows 2003 SMP
 * fix extboot stomping on reserved interrupt vectors (H. Peter Anvin)
 * remove unused -translation option (Anthony Liguori)
 * fix preemption during copy_from_user_inatomic() on older hosts (Andrea Arcangeli)
 * fix ppc cpu initialization (Hollis Blanchard)
 * drop shadow ptes on memslot destruction (Marcelo Tosatti)
 * improve invalid shadow root page table handling (Marcelo Tosatti)
 * remove redundant check for real mode (Mohammed Gamal)
 * add clflush emulation (Glauber Costa)
 * fix race setting shadow ptes on i386
 * fix interrupt reinjection in real mode (Jan Kiszka)
 * x86 hardware task switching fixes (Marcelo Tosatti)
 * fix interrupts being delayed by instruction emulation
  * improves Vista stability
 * fix reloading kvm-intel.ko while changing parameters (Sheng Yang)
 * fix reboot exception entry build bug (Ingo Molnar)
 * ignore no-op DEBUGCTL msr writes (Alexander Graf)
  * fixes Netware
 * fix irq state leak on ia64 (Julia Lawall)
 * s390 fixes (Carsten Otte, Christian Borntraeger, Martin Schwidefsky)
 * avoid guest tlb flushes on guest privilege switches (Hollis Blanchard)

Most of these look like we would want them in lenny.

 * merge qemu-svn
  * adds Virtual Distributed Ethernet (vde) support

I'll review the qemu changes to assess the impact of the merge.

 * adjust external module for 2.6.27 hosts
 * simplify mmu page zapping
 * simplify interrupt processing on Intel
 * remove hypercall device (Anthony Liguori)
 * remove duplicate monitor command (Anthony Liguori)
 * remove unused function declaration (Anthony Liguori)
 * remove unnecessary change to TARGET_PAGE_SIZE (Anthony Liguori)
 * remove qemu/kvm application decoration (Anthony Liguori)
 * add 'info kvm' monitor command  (Anthony Liguori)
 * consolidate pic isr clearing into a function
 * consolidate exception interrupt vector #defines (Jan Kiszka)
 * unify guest register save/restore code
 * optimize vmx by avoiding saving the host stack pointer
 * s390 libkvm port (Carsten Otte)
 * ppc guest breakpoint support (Hollis Blanchard)
 * optimize ppc by not saving host tlb state (Hollis Blanchard)
 * reduce ppc guest tlb writes (Hollis Blanchard)
 * ppc kvmtrace support (Christian Ehrhardt)

These are low impact or change ppc/s390 (which is not used in the debian

So i see three options right now: 
- keep the current version:
  many lenny users will need to get an updated kvm elsewhere,
  especially if they need migration (backports.org, unstable)
- fix just alsa and migration
  only some users will probably be affected by the bugs fixed between kvm-71
  and -72
- update to kvm-72
  potentially introduce regressions

I think that by trying to backport the many fixes from kvm-72 to the
current package i'm more likely to introduce regressions than by just
taking kvm-72.

How should i proceed now? For now i'll continue reviewing upstream's


Reply to: