[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] CPUID feature bits not saved with migration
From: |
Andre Przywara |
Subject: |
Re: [Qemu-devel] CPUID feature bits not saved with migration |
Date: |
Thu, 16 Jul 2009 12:08:53 +0200 |
User-agent: |
Thunderbird 2.0.0.14 (X11/20080508) |
Anthony Liguori wrote:
Andre Przywara wrote:
Hi,
while testing the guest multi-core code, I realized that all of the
cpuid_* values (like cpuid_ext_features,...) from CPUX86State are not
dumped in the migration stream. Is this intentional behavior (to let
the user specify other bits in the target?) or has this just been
forgotten?
Does KVM call the SET_CPUID2 ioctl after or before migration?
The cpuid bits are specified by the user. They aren't changable by the
guest which is why they haven't been migrated.
OK, I see your point. What has happened with the idea of using a
separate savevm section to transfer the guest configuration parts?
It's unclear what to do about -cpu host. If we did migrate cpuid
values, then -cpu would effectively be ignored after an incoming migration.
You do not want to migrate with -cpu host, this is only for a desktop
virtualization use-case where you are pretty sure that you will not
migrate. I have started working on "-cpu migrate", which uses some kind
of least common denominator bits for the KVM case (that is all CPUs with
hardware virtualization support). Currently there seems to be not much
difference to qemu64, so maybe we don't need it.
Regards,
Andre.
--
Andre Przywara
AMD-Operating System Research Center (OSRC), Dresden, Germany
Tel: +49 351 448 3567 12
----to satisfy European Law for business letters:
Advanced Micro Devices GmbH
Karl-Hammerschmidt-Str. 34, 85609 Dornach b. Muenchen
Geschaeftsfuehrer: Thomas M. McCoy; Giuliano Meroni
Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen
Registergericht Muenchen, HRB Nr. 43632
- [Qemu-devel] CPUID feature bits not saved with migration, Andre Przywara, 2009/07/15
- Re: [Qemu-devel] CPUID feature bits not saved with migration, Anthony Liguori, 2009/07/15
- Re: [Qemu-devel] CPUID feature bits not saved with migration, Jamie Lokier, 2009/07/15
- Re: [Qemu-devel] CPUID feature bits not saved with migration, Andre Przywara, 2009/07/16
- Re: [Qemu-devel] CPUID feature bits not saved with migration, Jamie Lokier, 2009/07/16
- Re: [Qemu-devel] CPUID feature bits not saved with migration, Andre Przywara, 2009/07/22
- Re: [Qemu-devel] CPUID feature bits not saved with migration, Jamie Lokier, 2009/07/22
Re: [Qemu-devel] CPUID feature bits not saved with migration,
Andre Przywara <=