[gentoo-user] qemu-kvm replacement

[gentoo-user] qemu-kvm replacement

[Heiko Zinke]

Hi,

with my recent qemu update from 1.6 to 2.0 I got the following error:

* The kvm/qemu-kvm wrappers no longer exist, but your libvirt
 * instances are still pointing to it.  Please update your
 * configs in /etc/libvirt/qemu/ to use the -enable-kvm flag
 * and the right system binary (e.g. qemu-system-x86_64).
 * ERROR: app-emulation/qemu-2.0.0::gentoo failed (pretend phase):
 *   update your virt configs to not use qemu-kvm
 * 
 * Call stack:
 *           ebuild.sh, line  93:  Called pkg_pretend
 *   qemu-2.0.0.ebuild, line 225:  Called die
 * The specific snippet of code:
 *              die "update your virt configs to not use qemu-kvm"

I found this bug which explains the why but sadly not the how.
https://bugs.gentoo.org/show_bug.cgi?id=506566

I need to get rid of the reference to the /usr/bin/qemu-kvm shell script which 
is basically only a wrapper for "exec /usr/bin/qemu-system-x86_64 -machine 
accel=kvm "$@""

So if I "sudo virsh edit vmname" and substitute "/usr/bin/qemu-kvm" by 
"/usr/bin/qemu-system-x86_64 -machine accel=kvm -enable-kvm" I only get this 
error :(
"error: Cannot check QEMU binary /usr/bin/qemu-system-x86_64 -machine 
accel=kvm -enable-kvm: No such file or directory"

How is this supposed to work? Do I need to create a custom shell skript or 
just use /usr/bin/qemu-system-x86_64 w/o the args an hope it  magically uses 
kvm acceleration?

thanks for the help!
heiko
-- 
Just go ahead and write your own multitasking multiuser os!
Worked for me all the times.
        -- Linus Torvalds

Re: [gentoo-user] qemu-kvm replacement

[Rich Freeman]

On Tue, Jun 10, 2014 at 5:31 PM, Heiko Zinke <mails@rabuju.com> wrote:
>
> So if I "sudo virsh edit vmname" and substitute "/usr/bin/qemu-kvm" by
> "/usr/bin/qemu-system-x86_64 -machine accel=kvm -enable-kvm" I only get this
> error :(
> "error: Cannot check QEMU binary /usr/bin/qemu-system-x86_64 -machine
> accel=kvm -enable-kvm: No such file or directory"

I replaced /usr/bin/qemu-kvm with /usr/bin/qemu-system-x86_64 and
everything worked fine.

However, perhaps leaving out the --enabled-kvm will cause some
problem.  If you do need to pass a parameter there may be some other
way to specify it - I'd have to read the xsd or the docs.

Rich

[gentoo-user] Re: qemu-kvm replacement

[walt]

On 06/10/2014 02:31 PM, Heiko Zinke wrote:
> Hi,
> 
> with my recent qemu update from 1.6 to 2.0 I got the following error:
> 
> * The kvm/qemu-kvm wrappers no longer exist, but your libvirt
>  * instances are still pointing to it.  Please update your
>  * configs in /etc/libvirt/qemu/ to use the -enable-kvm flag
>  * and the right system binary (e.g. qemu-system-x86_64).
>  * ERROR: app-emulation/qemu-2.0.0::gentoo failed (pretend phase):
>  *   update your virt configs to not use qemu-kvm
>  * 
>  * Call stack:
>  *           ebuild.sh, line  93:  Called pkg_pretend
>  *   qemu-2.0.0.ebuild, line 225:  Called die
>  * The specific snippet of code:
>  *              die "update your virt configs to not use qemu-kvm"
> 
> I found this bug which explains the why but sadly not the how.
> https://bugs.gentoo.org/show_bug.cgi?id=506566
> 
> I need to get rid of the reference to the /usr/bin/qemu-kvm shell script which 
> is basically only a wrapper for "exec /usr/bin/qemu-system-x86_64 -machine 
> accel=kvm "$@""
> 
> So if I "sudo virsh edit vmname" and substitute "/usr/bin/qemu-kvm" by 
> "/usr/bin/qemu-system-x86_64 -machine accel=kvm -enable-kvm" I only get this 
> error :(
> "error: Cannot check QEMU binary /usr/bin/qemu-system-x86_64 -machine 
> accel=kvm -enable-kvm: No such file or directory"
> 
> How is this supposed to work? Do I need to create a custom shell skript or 

> just use /usr/bin/qemu-system-x86_64 w/o the args an hope it  magically uses 
> kvm acceleration?

I believe "accel=kvm" is obsolete now.  "-enable-kvm" is the magic word
lately.  Try "qemu-system-x86_64 -help" for more info than you want :)

Re: [gentoo-user] Re: qemu-kvm replacement

[Mike Gilbert]

On Tue, Jun 10, 2014 at 7:45 PM, walt <w41ter@gmail.com> wrote:
> On 06/10/2014 02:31 PM, Heiko Zinke wrote:
>> Hi,
>>
>> with my recent qemu update from 1.6 to 2.0 I got the following error:
>>
>> * The kvm/qemu-kvm wrappers no longer exist, but your libvirt
>>  * instances are still pointing to it.  Please update your
>>  * configs in /etc/libvirt/qemu/ to use the -enable-kvm flag
>>  * and the right system binary (e.g. qemu-system-x86_64).
>>  * ERROR: app-emulation/qemu-2.0.0::gentoo failed (pretend phase):
>>  *   update your virt configs to not use qemu-kvm
>>  *
>>  * Call stack:
>>  *           ebuild.sh, line  93:  Called pkg_pretend
>>  *   qemu-2.0.0.ebuild, line 225:  Called die
>>  * The specific snippet of code:
>>  *              die "update your virt configs to not use qemu-kvm"
>>
>> I found this bug which explains the why but sadly not the how.
>> https://bugs.gentoo.org/show_bug.cgi?id=506566
>>
>> I need to get rid of the reference to the /usr/bin/qemu-kvm shell script which
>> is basically only a wrapper for "exec /usr/bin/qemu-system-x86_64 -machine
>> accel=kvm "$@""
>>
>> So if I "sudo virsh edit vmname" and substitute "/usr/bin/qemu-kvm" by
>> "/usr/bin/qemu-system-x86_64 -machine accel=kvm -enable-kvm" I only get this
>> error :(
>> "error: Cannot check QEMU binary /usr/bin/qemu-system-x86_64 -machine
>> accel=kvm -enable-kvm: No such file or directory"
>>
>> How is this supposed to work? Do I need to create a custom shell skript or
>
>> just use /usr/bin/qemu-system-x86_64 w/o the args an hope it  magically uses
>> kvm acceleration?
>
> I believe "accel=kvm" is obsolete now.  "-enable-kvm" is the magic word
> lately.  Try "qemu-system-x86_64 -help" for more info than you want :)
>

Reading through the source code, -enable-kvm seems to be equivalent to
-machine accel=kvm.

Re: [gentoo-user] qemu-kvm replacement

[Mike Gilbert]

On Tue, Jun 10, 2014 at 5:36 PM, Rich Freeman <rich0@gentoo.org> wrote:
> On Tue, Jun 10, 2014 at 5:31 PM, Heiko Zinke <mails@rabuju.com> wrote:
>>
>> So if I "sudo virsh edit vmname" and substitute "/usr/bin/qemu-kvm" by
>> "/usr/bin/qemu-system-x86_64 -machine accel=kvm -enable-kvm" I only get this
>> error :(
>> "error: Cannot check QEMU binary /usr/bin/qemu-system-x86_64 -machine
>> accel=kvm -enable-kvm: No such file or directory"
>
> I replaced /usr/bin/qemu-kvm with /usr/bin/qemu-system-x86_64 and
> everything worked fine.
>
> However, perhaps leaving out the --enabled-kvm will cause some
> problem.  If you do need to pass a parameter there may be some other
> way to specify it - I'd have to read the xsd or the docs.
>

Using /usr/bin/qemu-system-x86_64 should be fine. It looks like
libvirt will automatically append accel=kvm to the machine options,
which is equivalent to -enable-kvm.