[Qemu-devel] qemu ELF Loader Kernel integration

[Qemu-devel] qemu ELF Loader Kernel integration

[Philipp Gühring]

Hi,

Is it possible to integrate qemu(-ppc) into the Linux kernel, so that when a 
program tries to start a Linux-ELF-ppc executable, that qemu is being used to 
start it normally?

It would be useful for embedded systems development for cross-compilation:
The resulting binaries could be tried natively on the development system. 
If I would do it manually, I could start 
qemu-ppc binary
But in some enviroments, the binary is started automatically by a third-party 
product, therefore being able to launch the binary directly would be helpful.

Regards,
-- 
Philipp Gühring

Re: [Qemu-devel] qemu ELF Loader Kernel integration

[Panagiotis Issaris]

Hi,

Philipp Gühring schreef:

>Hi,
>
>Is it possible to integrate qemu(-ppc) into the Linux kernel, so that when a 
>program tries to start a Linux-ELF-ppc executable, that qemu is being used to 
>start it normally?
>
>It would be useful for embedded systems development for cross-compilation:
>The resulting binaries could be tried natively on the development system. 
>If I would do it manually, I could start 
>qemu-ppc binary
>But in some enviroments, the binary is started automatically by a third-party 
>product, therefore being able to launch the binary directly would be helpful.
>  
>
Yes, have a look at linux-2.6.11/Documentation/binfmt_misc.txt.

With friendly regards,
Takis


-- 
  K.U.Leuven, Mechanical Eng.,  Mechatronics & Robotics Research Group
  http://people.mech.kuleuven.ac.be/~pissaris/

Re: [Qemu-devel] qemu ELF Loader Kernel integration

[Valtteri Rahkonen]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 988 bytes --]

On Thu, 31 Mar 2005, PhilippGühring wrote:
> Hi,
>
> Is it possible to integrate qemu(-ppc) into the Linux kernel, so that when a
> program tries to start a Linux-ELF-ppc executable, that qemu is being used to
> start it normally?

Yes, see binfmt_misc (kernel support for misc binaries).

> It would be useful for embedded systems development for cross-compilation:
> The resulting binaries could be tried natively on the development system.
> If I would do it manually, I could start
> qemu-ppc binary
> But in some enviroments, the binary is started automatically by a third-party
> product, therefore being able to launch the binary directly would be helpful.

If you have a binfmt_misc compiled to your kernel and you have registered 
qemu as a ppc interpreter then qemu will be started automatically when 
executing the ppc binaries. You will need to register qemu as your 
interprer in proc interface (/proc/sys/fs/binfmt_misc/register).

--
Valtteri Rahkonen

[Qemu-devel] Re: qemu ELF Loader Kernel integration

[mirak]

Valtteri Rahkonen wrote:
> On Thu, 31 Mar 2005, PhilippGühring wrote:
> 
>> Hi,
>>
>> Is it possible to integrate qemu(-ppc) into the Linux kernel, so that 
>> when a
>> program tries to start a Linux-ELF-ppc executable, that qemu is being 
>> used to
>> start it normally?
> 
> 
> Yes, see binfmt_misc (kernel support for misc binaries).
> 
>> It would be useful for embedded systems development for 
>> cross-compilation:
>> The resulting binaries could be tried natively on the development system.
>> If I would do it manually, I could start
>> qemu-ppc binary
>> But in some enviroments, the binary is started automatically by a 
>> third-party
>> product, therefore being able to launch the binary directly would be 
>> helpful.
> 
> 
> If you have a binfmt_misc compiled to your kernel and you have 
> registered qemu as a ppc interpreter then qemu will be started 
> automatically when executing the ppc binaries. You will need to register 
> qemu as your interprer in proc interface 
> (/proc/sys/fs/binfmt_misc/register).

Would this work for for exemple the flash player plugin or is it only 
for executables ?
I am interested in doing that the other way around, for i386 code on 
linux ppc.

Re: [Qemu-devel] Re: qemu ELF Loader Kernel integration

[Mark Williamson]

> > If you have a binfmt_misc compiled to your kernel and you have
> > registered qemu as a ppc interpreter then qemu will be started
> > automatically when executing the ppc binaries. You will need to register
> > qemu as your interprer in proc interface
> > (/proc/sys/fs/binfmt_misc/register).
>
> Would this work for for exemple the flash player plugin or is it only
> for executables ?
> I am interested in doing that the other way around, for i386 code on
> linux ppc.

Shared libraries (like Netscape plugins) are a different matter: they need to 
interface intimately with the native code - you can't run part of an app. in 
QEmu.

Last time this came up, somebody suggested that you might be OK with x86 
Mozilla, with the x86 flash plugin, all under QEmu.  I've not tried this, 
YMMV ;-)

HTH,
Mark

Re: [Qemu-devel] Re: qemu ELF Loader Kernel integration

[David Woodhouse]

On Fri, 2005-04-01 at 02:32 +0100, Mark Williamson wrote:
> Shared libraries (like Netscape plugins) are a different matter: they need to 
> interface intimately with the native code - you can't run part of an app. in 
> QEmu.
> 
> Last time this came up, somebody suggested that you might be OK with x86 
> Mozilla, with the x86 flash plugin, all under QEmu.  I've not tried this, 
> YMMV ;-)

You probably don't actually need to use an i386 Mozilla. Mozilla can use
external _programs_ displaying within its window; I use mozplugger with
the i386 acroread on PPC, for example. You could just run the flash
player _itself_ in a separate process, with a wrapper of your own to
make it think it's running in an i386 Mozilla.

Or just use swfdec.

-- 
dwmw2

Re: [Qemu-devel] qemu ELF Loader Kernel integration

[Lennert Buytenhek]

On Thu, Mar 31, 2005 at 10:48:37AM +0200, Philipp Gühring wrote:

> Is it possible to integrate qemu(-ppc) into the Linux kernel, so that
> when a program tries to start a Linux-ELF-ppc executable, that qemu
> is being used to start it normally?

Something like that is already available, see qemu-binfmt-conf.sh


--L