Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

[Thomas Huth]

On 30.08.2017 09:55, Mahmood wrote:
>> You don't have to write "fsdriver" here, but replace it with "local",
>> "handle" or "proxy".
> 
> Still get the same error
> 
> mahmood@cluster:qemu-vm$ qemu-system-x86_64 -m 4000 -cpu Opteron_G5 -smp 2 -hda centos7server.img -boot c  -usbdevice tablet -enable-kvm -device e1000,netdev=host_files -netdev user,net=10.0.2.0/24,id=host_files -virtfs local,id=shared,path=/home/mahmood/Downloads,mount_tag=Downloads 
> qemu-system-x86_64: -virtfs local,id=shared,path=/home/mahmood/Downloads,mount_tag=Downloads: Parameter 'driver' expects device type 

Hmm, I've got the strange feeling that the -virtfs parameter might
currently be broken.

Could you please try to replace the -virtfs option with these two options:

 -fsdev local,id=shared,path=/home/mahmood/Downloads \
 -device virtio-9p-pci,fsdev=shared,mount_tag=Downloads

I hope that works better...

 Thomas

Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

[Mahmood]

>Could you please try to replace the -virtfs option with these two options:
>
 >-fsdev local,id=shared,path=/home/mahmood/Downloads \
 >-device virtio-9p-pci,fsdev=shared,mount_tag=Downloads




Still get the same error!

mahmood@cluster:qemu-vm$ qemu-system-x86_64 -m 4000 -cpu Opteron_G5 -smp 2 -hda centos7server.img -boot c  -usbdevice tablet -enable-kvm -device e1000,netdev=host_files -netdev user,net=10.0.2.0/24,id=host_files -fsdev local,id=shared,path=/home/mahmood/Downloads -device virtio-9p-pci,fsdev=shared,mount_tag=Downloads
qemu-system-x86_64: -device virtio-9p-pci,fsdev=shared,mount_tag=Downloads: Parameter 'driver' expects device type
mahmood@cluster:qemu-vm$




Regards,
Mahmood

Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

[Greg Kurz]

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On Wed, 30 Aug 2017 09:28:57 +0000 (UTC)
Mahmood <nt_mahmood@yahoo.com> wrote:

> >Could you please try to replace the -virtfs option with these two options:
> >
>  >-fsdev local,id=shared,path=/home/mahmood/Downloads \
>  >-device virtio-9p-pci,fsdev=shared,mount_tag=Downloads  
> 
> 
> 
> 
> Still get the same error!
> 
> mahmood@cluster:qemu-vm$ qemu-system-x86_64 -m 4000 -cpu Opteron_G5 -smp 2 -hda centos7server.img -boot c  -usbdevice tablet -enable-kvm -device e1000,netdev=host_files -netdev user,net=10.0.2.0/24,id=host_files -fsdev local,id=shared,path=/home/mahmood/Downloads -device virtio-9p-pci,fsdev=shared,mount_tag=Downloads
> qemu-system-x86_64: -device virtio-9p-pci,fsdev=shared,mount_tag=Downloads: Parameter 'driver' expects device type
> mahmood@cluster:qemu-vm$
> 

Hi,

Both -virtfs and -fsdev/-device syntaxes work for me with the current QEMU
master branch :) Where's your qemu-system-x86_64 binary coming from ?

Cheers,

--
Greg

PS: I'm on vacation. I'll be fully available next week.


> 
> 
> 
> Regards,
> Mahmood
> 


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Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

[Thomas Huth]

On 30.08.2017 12:11, Greg Kurz wrote:
[...]
> Hi,
> 
> Both -virtfs and -fsdev/-device syntaxes work for me with the current QEMU
> master branch :) Where's your qemu-system-x86_64 binary coming from ?

There is at least one problem with -virtfs if you forget to specify
the "security_model=xxx" option:

$ x86_64-softmmu/qemu-system-x86_64 -virtfs local,id=shared,path=/tmp,mount_tag=tag
qemu-system-x86_64: util/qemu-option.c:547: opt_set: Assertion `opt->str' failed.
Aborted (core dumped)

According to the qemu-doc, the securit_model is optional, so it
should be possible to run qemu without it, too, shouldn't it?

 Thomas

Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

[Mahmood]

The security_model=none also doesn't work and get the same error.

mahmood@cluster:qemu-vm$ qemu-system-x86_64 -version
QEMU emulator version 1.7.0, Copyright (c) 2003-2008 Fabrice Bellard


I know it is old but I think I installed this version three years ago due to the Rocks-6 version old libraries (which is based on Centos-6). I will try some newer versions to find which version is better.


One more question. How can I uninstall the qemu which is built from source? "make uninstall" in the source folder doesn't work.


Sorry for taking up your time.


Regards,
Mahmood

Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

[Mahmood]

Hello again,I installed 2.5.0 quickly and it was pretty straight forward!

Here is the error message I get regarding the 'virtio-9p-pci'



mahmood@cluster:qemu-vm$ qemu-system-x86_64 -m 4000 -cpu Opteron_G5 -smp 2 -hda centos7.img -boot c  -usbdevice tablet -enable-kvm -device e1000,netdev=host_files -netdev user,net=10.0.2.0/24,id=host_files -virtfs local,id=shared,path=/home/mahmood/Downloads,mount_tag=Downloads
warning: host doesn't support requested feature: CPUID.40000001H:EAX.kvm_asyncpf [bit 4]
warning: host doesn't support requested feature: CPUID.40000001H:EAX.kvm_asyncpf [bit 4]
qemu-system-x86_64: -virtfs local,id=shared,path=/home/mahmood/Downloads,mount_tag=Downloads: 'virtio-9p-pci' is not a valid device model name
mahmood@cluster:qemu-vm$ qemu-system-x86_64 -m 4000 -cpu Opteron_G5 -smp 2 -hda centos7.img -boot c  -usbdevice tablet -enable-kvm -device e1000,netdev=host_files -netdev user,net=10.0.2.0/24,id=host_files -fsdev local,id=shared,path=/home/mahmood/Downloads -device virtio-9p-pci,fsdev=shared,mount_tag=Downloads
warning: host doesn't support requested feature: CPUID.40000001H:EAX.kvm_asyncpf [bit 4]
warning: host doesn't support requested feature: CPUID.40000001H:EAX.kvm_asyncpf [bit 4]
qemu-system-x86_64: -device virtio-9p-pci,fsdev=shared,mount_tag=Downloads: 'virtio-9p-pci' is not a valid device model name
mahmood@cluster:qemu-vm$ qemu-system-x86_64 -version
QEMU emulator version 2.5.0, Copyright (c) 2003-2008 Fabrice Bellard






I appreciate if you help. Thanks.


Regards,
Mahmood

Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

[Peter Maydell]

On 30 August 2017 at 12:38, Mahmood <nt_mahmood@yahoo.com> wrote:
> Hello again,I installed 2.5.0 quickly and it was pretty straight forward!
>
> Here is the error message I get regarding the 'virtio-9p-pci'
> 'virtio-9p-pci' is not a valid device model name

Are you building your own QEMU binary or is it from somewhere
else? I wonder if it was built without support for the 9p
filesystem code. For this to be enabled:
 * host machine must be Linux
 * system building QEMU must have libcap development package installed

If you're building it yourself then you can pass configure
'--enable-virtfs' which will mean configure will stop with
an error if it can't enable virtfs rather than just disabling
this optional feature.

QEMU ought to produce a helpful error if you try to use -virtfs
when virtfs wasn't compiled in, but it may be that this check
was broken accidentally at some point.

Also, 2.5.0 is a couple of years old, you might try with 2.9.0
(or even with the 2.10.0 we're about to release today).

thanks
-- PMM

Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

[Greg Kurz]

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On Wed, 30 Aug 2017 12:17:22 +0200
Thomas Huth <th.huth@posteo.de> wrote:

> On 30.08.2017 12:11, Greg Kurz wrote:
> [...]
> > Hi,
> > 
> > Both -virtfs and -fsdev/-device syntaxes work for me with the current QEMU
> > master branch :) Where's your qemu-system-x86_64 binary coming from ?  
> 
> There is at least one problem with -virtfs if you forget to specify
> the "security_model=xxx" option:
> 
> $ x86_64-softmmu/qemu-system-x86_64 -virtfs local,id=shared,path=/tmp,mount_tag=tag
> qemu-system-x86_64: util/qemu-option.c:547: opt_set: Assertion `opt->str' failed.
> Aborted (core dumped)
> 

Yeah, we should print out that security_model is missing instead of dumping
core... :-\

> According to the qemu-doc, the securit_model is optional, so it
> should be possible to run qemu without it, too, shouldn't it?
> 

Hmm... the documentation is a bit misleading. We indeed have:

-virtfs fsdriver[,path=path],mount_tag=mount_tag[,security_model=security_model]
        [,writeout=writeout][,readonly][,socket=socket|sock_fd=sock_fd]

but the description of security_model says: 

Security model is mandatory only for local fsdriver. Other fsdrivers (like
handle, proxy) don't take security model as a parameter.

The same goes for the proxy fsdriver which needs socket or sock_fd, and doesn't use
path.

Should we have a -virtfs line for each fsdriver ?

>  Thomas


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Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

[Mahmood]

OK. I reconfigured 2.9.0 with --enable-virtfs. Please note:
1- If I use -virtfs option, I get 
     qemu-option.c:547: opt_set: Assertion `opt->str' failed

2- If I use -fsdev and -device, then I *must* use security_model

3- If I use -fsdev and -device and security_model, then the guest boots normally.

I haven't tried to see if I am able to access the shared folder nor not. Do you have any note on the above items?


Regards,
Mahmood

Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

[Greg Kurz]

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On Wed, 30 Aug 2017 14:35:00 +0000 (UTC)
Mahmood <nt_mahmood@yahoo.com> wrote:

> OK. I reconfigured 2.9.0 with --enable-virtfs. Please note:
> 1- If I use -virtfs option, I get 
>      qemu-option.c:547: opt_set: Assertion `opt->str' failed
> 

If you use the local fsdriver, security_model is mandatory with -virtfs just
like it is with -fsdev.

> 2- If I use -fsdev and -device, then I *must* use security_model
> 

True, as indicated in the QEMU manpage:

"Security model is mandatory only for local fsdriver.
 Other fsdrivers (like handle, proxy) don't take security model
 as a parameter."

> 3- If I use -fsdev and -device and security_model, then the guest boots normally.
> 
> I haven't tried to see if I am able to access the shared folder nor not. Do you have any note on the above items?
> 
> 
> Regards,
> Mahmood
> 

Cheers,

--
Greg

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Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

[Mahmood]

Hello again,
For the command

    mount -t 9p -o trans=virtio Downloads /media/Downloads

inside the Centos-7 guest, I get this error

mount: unknown filesystem type '9p'

Any thought?

Regards,
Mahmood

Re: [Qemu-devel] [Qemu-discuss] Accessing a shared folder

[Peter Maydell]

On 31 August 2017 at 11:34, Mahmood via Qemu-devel
<qemu-devel@nongnu.org> wrote:
> Hello again,
> For the command
>
>     mount -t 9p -o trans=virtio Downloads /media/Downloads
>
> inside the Centos-7 guest, I get this error
>
> mount: unknown filesystem type '9p'
>
> Any thought?

That's an issue with your guest OS (probably it doesn't
have 9p support enabled in the kernel).

thanks
-- PMM